Assessing anxiety, depression and insomnia symptoms among Ebola survivors in Africa: A meta-analysis

Jeremiah W Acharibasam; Batholomew Chireh; Hayelom G Menegesha

doi:10.1371/journal.pone.0246515

. 2021 Feb 5;16(2):e0246515. doi: 10.1371/journal.pone.0246515

Assessing anxiety, depression and insomnia symptoms among Ebola survivors in Africa: A meta-analysis

Jeremiah W Acharibasam ¹, Batholomew Chireh ², Hayelom G Menegesha ^3,^*

Editor: John Schieffelin⁴

PMCID: PMC7864444 PMID: 33544772

Abstract

Background

During health disaster events such as the current devastating havoc being inflicted on countries globally by the SARS-CoV-19 pandemic, mental health problems among survivors and frontline workers are likely concerns. However, during such health disaster events, stakeholders tend to give more precedence to the socio-economic and biomedical health consequences at the expense of mental health. Meanwhile, studies show that regardless of the kind of disaster/antecedent, all traumatic events trigger similar post-traumatic stress symptoms among survivors, families, and frontline workers. Thus, our study investigated the prevalence of anxiety, depression and insomnia symptoms among survivors of the 2014–2016 Ebola virus disease that plagued the West African sub-region.

Methods

We systematically retrieved peer-reviewed articles published between 1970 and 2019 from seven electronic databases, including Google Scholar, MEDLINE, PsychInfo, PubMed, Scopus, Springer Link, Web of Science on Ebola and post-traumatic stress disorder symptoms. A comprehensive hand search complemented this literature search. Of the 87 articles retrieved, only 13 met the inclusion criteria for this meta-analysis.

Results

After heterogeneity, influence, and publication bias analysis, our meta-analysis pooled proportion effects estimates showed a moderate to a high prevalence of anxiety (14%; 99% CI: 0.05–0.30), depression (15%; 99% CI: 0.11–0.21), and insomnia (22%; 99% CI: 0.13–0.36). Effect estimates ranging from (0.13; 99% CI: 0.05, 0.28) through to (0.11; 99% CI: 0.05–0.22), (0.15; 99% CI: 0.09–0.25) through to (0.13; 99% CI: 0.08–0.21) and (0.23; 99% CI: 0.11–0.41) to (0.23; 99% CI: 0.11–0.41) were respectively reported for anxiety, depression and insomnia symptoms. These findings suggest a significant amount of EVD survivors are struggling with anxiety, depression and insomnia symptoms.

Conclusion

Our study provided the first-ever meta-analysis evidence of anxiety, depression, and insomnia symptoms among EVD survivors, and suggest that the predominant biomedical health response to regional and global health disasters should be complemented with trauma-related mental health services.

Introduction

The Ebola virus disease (EVD) has a long history in Africa, dating back to 1976, where 318 cases and 280 deaths were first recorded in the Democratic Republic of Congo [1]. Most recently, two more outbreaks were reported in the Democratic Republic of Congo (DRC). The first started in May 2018 at the Equateur region of DRC and lasted for two months with 58 cases, and 27 deaths reported [2]. The second DRC outbreak started in August 2018 at North Kivu region and is ongoing [3] with 3453 cases (3310 confirmed and 143 probable) as well as 2273 deaths and 1169 survivors reported as of 31^st March 2020 [3]. However, the recent Ebola virus disease outbreak that shook the foundations of already fragile health care systems primarily occurred between 2014–2016 in three West African countries namely Sierra Leone, Liberia and Guinea [4]. Its unprecedented nature resulted in a substantial increase in human suffering and deaths. According to WHO, an estimated 28, 646 confirmed cases and 11, 322 deaths were recorded within that period [4]. Several factors were attributed to this large-scale spread of the EVD. Apart from the resources constraints and already challenged healthcare systems in these West African countries [5,6], sociopolitical and cultural factors unique to the region [7] contributed significantly to the spread of the EVD virus. Despite the unprecedented EVD outbreak and its associated mortality and morbidity rates, it also recorded the highest number of survivors in the history of Ebola outbreaks. An estimated 10,000 people in the three West African countries survived the epidemic, according to WHO estimates [8].

In addition, regardless of the antecedent, traumatic events have been shown to trigger adverse psychological processes and experiences [9]. Thus, whether war victims, soldiers, victims of war disasters, first responders, or patients, the resulting post-traumatic psychological impact of these events is indistinguishable [10–12]. Unfortunately, it seems direct survivors/patients of health disasters like Ebola tend to receive lesser public health and policy attention than the other disaster events. This trend is no surprise as war veterans or war crimes are often perceived positively as national heroes or victimized minority groups, respectively. In contrast, survivors of health disasters such as infectious epidemics and pandemics can often be tagged with social suspicion and negative stigmatization. Post EVD survivors do not only face the traumatic experience of suffering from the disease but also have to deal with community fear and social stigmatisation issues within a society devastated by the outbreak [13,14]. Earlier epidemiological studies have documented the link between mental health problems and infectious diseases outbreaks [15,16].

Also, symptoms of anxiety, depression, and insomnia are found to be the most predominant mental health issues reported among post-disaster survivors (war veterans, Ebola survivors etc.) during and after an outbreak event [12,17–19]. Therefore, adverse mental health outcomes such as experience with ill individuals, perceptions of threat, high levels of mortality, food and resource insecurity, stigma and discrimination, and intolerance of uncertainty could be expected during and after the Ebola epidemic in the affected African countries.

However, research has shown that mental health issues are mostly neglected in low- and middle-income countries [20], which is often accompanied by minimal allocation of resources to mental health care. For instance, in 2015, a World Bank report noted that as of the time of the Ebola outbreak, the number of mental health workers (including psychiatrists) in the local population was as low as 1 in 6 million in Sierra Leone and 1 in 25,000 in Liberia [19]. This evidence exemplifies the tremendous need for both additional resources and novel approaches in outreach and treatment of mental health burden in West Africa. Also, one of the major reasons for the devastating Ebola outbreak was the initial slow response from international health partners [21,22]. Even when the support finally comes, current Western post-disaster health aid to tackling African epidemics seem to prioritize the biomedical interventions to the neglect of mental health [21,22]. This predominantly biased biomedical public health approach to post-disaster interventions may lead to inequitable distribution of health resources in these affected regions. Also, international humanitarian donor agencies that prioritize funding for a biomedical response over a complementary mental health one may continue to feed into a persisting biomedical-first approach at the expense of alternatives that incorporate mental health needs of survivors [21,22].

Therefore, continuing to promote the biomedical approach may unintentionally further weaken developing countries’ capacity to effectively handle health crisis post-disaster mental health care needs of survivors. Also, as victims of health crisis do not only have to deal with the stress and trauma of surviving the illness but also the community stigmatizing reaction to them for falling ill, contact tracing can be affected during critical health disasters. Therefore, the goal of this study is to draw attention to the health crisis-induced post-traumatic stress disorder symptoms among survivors pandemics and epidemics, especially those in poorer countries. Our specific aim is to provide a meta-analysis effects estimates of the prevalence of anxiety, depression and insomnia symptoms (per the definition of the DSM-5) among African EVD survivors.

Currently, the majority of existing reviews have been qualitative assessments of psychological and neuropsychological consequences, lived experiences and coping strategies of Ebola disease among survivors [23,24]. Also, there appears to be non-existing meta-analysis evidence on the prevalence of anxiety, depression and insomnia symptoms as mental health burden among Ebola survivors in the affected countries in Africa. Thus, this meta-analysis presents a quantitative estimate of the prevalence of the above symptoms among EVD survivors. Providing this evidence could support clinical and policy efforts to improve post-health crisis interventions and resources allocation to mitigate the mental health impacts for survivors, families, and frontline workers.

Methods

Search strategy

The Preferred Reporting Items guide guided this Meta-Analysis for Systematic and Meta-Analysis (PRISMA) (See Fig 1) [25]. A systematic search was conducted on seven popular electronic databases, including Google Scholar, MEDLINE, PsychInfo, PubMed, Scopus, Springer Link, Web of Science to retrieve all available relevant literature on Ebola and post-traumatic stress disorder symptoms. Furthermore, a follow-up comprehensive hand search was carried out to enable us to capture grey literature, including thesis and dissertation works. Our exhaustive and rigorous search of literature helped to reduce the risk of leaving out important studies that could affect the quality of our meta-analysis conclusions [26]. Also, to ensure replicability, the same key terms were used across all the databases, including “post-traumatic stress disorder*”, “post-Ebola syndrome*”, PTSD, Ebola, “Ebola Virus*”, “Ebola disease*”, “Ebola hemorrhagic fever”, survivor, “Ebola survivor*”, Africa*. We identified these key terms from relevant literature and MeSH terms in the various databases. We performed the searches on 14 January 2020. Please, find a sample of one of our search queries in S1 File. Ethical approval for this study was not necessary since it was a re-analysis of already published literature that can be accessed publicly.

Inclusion/Exclusion criteria

The following inclusion/exclusion criteria were used for articles selection: 1) published between January 1, 1970, and December 31, 2019; 2) written in the English Language; 3) original and peer-reviewed; 4) cohort, cross-sectional, case-control and 5) from any African country. We did not include a specific age restriction for participants studied. However, we restricted our definition of anxiety, depression and insomnia to the one given by the DSM-5 [17]. Thus, we focused on studies that included any of the specified symptoms of anxiety, depression and insomnia per the DSM v5 definition due to that there was a paucity of existing literature. Another caveat was that only studies that provided raw frequency or proportion data on any of the known anxiety, depression and insomnia symptoms [17] and demographic information among Ebola survivors were included. This restriction was added to allow us to conduct proportional effect size meta-analysis and diagnostic analysis on the included studies. For studies meeting the inclusion criteria but for which data could not be obtained in the article or the journal supplementary files’ database, we contacted the authors via email to obtain raw data. Only a few of the authors contacted responded, and a couple still had the relevant data. Thus, we decided to restrict our analysis to only studies with complete data.

We excluded studies that were: 1) focused on Ebola and other non-mental health symptoms (anxiety, depression and insomnia); 2) done on non-human subjects; 3) conducted outside of Africa; 4) review studies, news articles, commentaries, letters and editorials, and 5) published before 1970. Studies that lacked raw frequency data but provided other results, including odds ratios, were discarded.

Search results

We retrieved a total of 74 articles from the databases searched (Google scholar N = 29; Scopus N = 24; PubMed N = 8; Web of Science N = 7; Ovid Medline N = 3; Springer Link N = 2; Ovid PsycInfo N = 1). Also, the rigorous hand search returned 13 additional relevant articles on Ebola and symptoms of anxiety, depression and insomnia. Thus, a total of 87 electronic articles were obtained from the systematic literature search. From the 87 articles, 30 duplicates were discarded, and an additional 17 were removed after screening their titles and abstracts as they did not meet the inclusion criteria. Afterwards, 27 of the remaining 40 studies that failed to meet further inclusion limitations were eliminated after a full-text reading. Therefore, a remaining total of 13 articles were included in the meta-analysis (refer to Table 1 for a list of the added articles).

Table 1. Summary of studies’ attributes.

First Author	Year	Setting	Study Design	Sample Size	Age (mean/median)	Follow–up (years)	Assessment of Health Outcome
Clark et al. [40]	2015	Uganda	Retrospective Cohort	49	40 (mean)	5 months	Standardized Questionnaires
Maurice et al. [41]	2018	Liberia	Retrospective Cohort	329	33(mean)	10 months	Medical reports
Etard et al. [42]	2017	Guinea	Cross-sectional	802	28.4 (median)	1 year, 4 months	Standardized Questionnaires and clinical assessment
Wadoum et al. [43]	2017	Sierra Leone	Prospective Cohort	246	27 (mean)	1 year, 3 days	Questionnaires and clinical laboratory assessment
Howlett et al. [44]	2018	Sierra Leone	Prospective Cohort	324	28 (median)	4 months	Medical reports
Keita et al. [45]	2017	Guinea	Prospective Cohort	256	31 (median)	1 year	Standardized Questionnaires
Kelly et al. [46]	2018	Congo	Cross-sectional	221	53.2 (mean)	2 months	Standardized Questionnaires
Mohammed et al. [47]	2017	Sierra Leone	Retrospective Cohort	115	28 (median)	1 year, 1 month	Medical reports
Mohammed et al. [48]	2015	Nigeria	Cross-sectional	117	34 (mean)	2 weeks	Standardized Questionnaires
Qureshi et al. [49]	2015	Guinea	Cross-sectional	105	38.9 (mean)	3 months	Standardized Questionnaires
Scott et al. [50]	2016	Sierra Leone	Cross-sectional	44	35 (median)	3 weeks	Medical reports
Tiffany et al. [51]	2016	Sierra Leone	Retrospective Cohort	166	24.7 (mean)	5 months	Standardized Questionnaires and clinical assessment
Wilson et al. [52]	2016	Liberia	Cross-sectional	268	30 (median)	4 months	Standardized Questionnaires

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Data collection and extraction

Author HGM was involved in the identification of the databases to be searched while authors J.W.A was responsible for the retrieval of articles from the electronic databases and author B.C. conducted the rigorous hand search for additional articles. Also, both authors independently examined all the 87 articles retrieved based on the above-stated eligibility criteria. Afterwards, 13 studies were included with information from independent samples on the following variables: country, design, sample, sex, age, follow-up period, stigma, anxiety, depression, insomnia. All the identified 13 studies presented raw frequency data enough for calculating summary statistics and proportional meta-analysis effects estimates with related 99% confidence intervals. An alpha level of 99% was used to ensure that the values of tau (T), tau-squared (T²), and between-study variance (I²) fall within the confidence intervals. For studies that met the inclusion criteria but did not have the required raw frequency data on the foregoing variables, Author J.W.A contacted authors via email to obtain this data. However, all articles providing insufficient data with no response from the contacted authors or failing to meet the inclusion criteria were ultimately discarded. Refer to Table 1 for details of the included studies and the related extracted. After retrieving all relevant research articles, author HGM was responsible for assuring the integrity of all data extracted.

Data analysis and synthesis

For statistical analysis convenience, we stratified the 13 articles based on the sufficiency of frequency data provided by each study on the examined anxiety, depression and insomnia symptoms. These articles were classified into three meta-analysis groupings: (1) Ebola and anxiety; (2) Ebola and depression; (3) Ebola and insomnia. The studies in these three categories provided enough raw data to allow us to calculate summary proportion statistics and pooled meta-analysis effect sizes with their associated 99% confidence intervals using the metaphor [27] and meta [28] R programming language packages (version 3.6.3) [29]. All summary proportion statistics and pooled effects, sampling variances, and 99% confidence intervals estimates were computed using the inverse variance method based on the logit transformation (PLO) measure and restricted maximum-likelihood estimator (REML) random-effects method.

We assessed heterogeneity across studies in each stratum using the Q-statistic X² [30] and the DerSimonian and Laird I² statistic [31,32]. Further posthoc sensitivity analysis was conducted to identify influential studies (i.e. outlier effect sizes) that accounted for the heterogeneity in the meta-analysis data by using the studentized residuals (i.e. z-values) with a cut-off value set at 2 [33]. A cut-off of 2 was chosen due to the small number (i.e. <25) of studies within each stratum (ibid). We then used the Leave-one-out diagnostic test [34] to further confirm the effect of each study on the overall mean and estimate for the observed summary proportion by removing each study in a step-wise manner (ibid). Since the studies in each stratum were small, we considered the outlier effects insignificant and retained the studies in the meta-analysis if the number of outliers was less than two studies.

After the outlier analysis, we proceed to assess for risk of publication bias within each analysis stratum using funnel plots [35] based on the standard errors and the Eagger test [36] because it performs comparatively better when the meta-analysis involves a small number of studies (i.e. <25). Specifically, we used Eager’s unweighted regression test because the traditional test is critiqued to have no theoretical justification [37]. However, we were unable to conduct subgroup/moderator and meta-regression analysis to account for the heterogeneity in effect sizes across the included studies because of the insufficiency of the data provided and the small number of studies under each analysis stratum [38,39]. Once all posthoc heterogeneity, diagnostic, and publication bias assessments were completed, we recalculated the meta-analysis summary proportion statistics and effect sizes and produced a final forest plot based on the precision of each study’s effect size.

Results

A total of 13 remaining articles were included in the meta-analysis [40–52]. Table 1 shows a detailed summary of the study attributes and data on the characteristics of the reviewed articles. Data were extracted based on the following features: country, design, sample, sex, age, follow-up period, presence of anxiety, depression, and insomnia. We considered the quality of the studies reviewed as high as there was no observed evidence of any publication bias.

Ebola and anxiety

Five studies [41,44,47,48,52] assessed the prevalence of anxiety among Ebola survivors in this study. Anxiety was assessed via medical reports and standardized questionnaires. Fig 2a shows the individual study and pooled proportion effect estimates. The pooled prevalence of anxiety in these studies was 0.14 (99% CI: 0.05–0.30; χ² = 45.91; I² = 94.63%; p < 0.01) among the EVD survivors, implying a significant level of anxiety. The absence of publication bias strengthens this finding (see Fig 2c). Most of the studies fell in the funnel plot within the 99% confidence interval and an Egger’s [29] unweighted regression test (p = 0.12) showed a lack of asymmetry. Also, a sensitivity analysis using the Leave-one-out technique [27] produced effect estimates ranging from 0.13 (99% CI: 0.05, 0.28) through to 0.11 (99% CI: 0.05–0.22), showing a minimal influence of any individual study on the overall proportional effect estimate (see Fig 2b). Thus, a significant prevalence of anxiety is found.

Fig 2 — a Forest plot of Ebola and anxiety studies using the random-effects model. b: Sensitivity plot of Ebola and anxiety studies. c: Funnel plot of Ebola and anxiety studies.

Ebola and depression

Nine studies [40–42,44,45,47–49,52] estimated the prevalence of depression and/or depressive symptoms among Ebola survivors. Depression and/or depressive symptoms were assessed through medical reports, standardized questionnaires and clinical assessment. The results in Fig 3a shows the individual study and pooled proportion effect estimates. A pooled prevalence effect estimates of 0.15 (99% CI: 0.11–0.21; χ² = 81.20; I² = 94.62%; p < 0.01) was reported, indicating a significant level of depression among EVD survivors. Publication bias assessments showed that half of the studies fell outside the funnel plots (Fig 3c), but Egger’s [36] regression test indicated the absence of asymmetry (p = 0.23). Thus, the sensitivity results (Fig 3b) generally showed the effects estimates of almost all the studies distributed evenly around the reference line. Our leave-one-out analysis [34] supported these results with effect estimates ranging from 0.15 (99% CI: 0.09–0.25) through to 0.13 (99% CI: 0.08–0.21), which shows the minimal impact of individual studies on the main proportion effect estimate.

Fig 3 — a Forest plot of Ebola and depression studies using random-effects model. b: Sensitivity plot of Ebola and depression studies. c: Funnel plot of Ebola and depression studies.

Ebola and insomnia

Ten studies [40,41,43,44,47–52] where insomnia was assessed through medical reports and standardized questionnaires. Fig 4a shows the individual study and pooled proportion effect estimates. We found a pooled proportion effect estimate of 0.22 (99% CI: 0.13–0.36; χ² = 238.09; I² = 94.62%; p < 0.01), which indicates a significant presence of insomnia among EVD survivors. The funnel plot (Fig 4c) shows that most of the studies fall in the 99% confidence interval, and Egger’s [29] regression test confirmed the absence of asymmetry (p = 0.51). The leave-one-out test [34] also showed the effect estimates ranging from 0.23 (99% CI: 0.11–0.41) to 0.23 (99% CI: 0.11–0.41) as each study is removed from the analysis. Thus, our sensitivity analysis showed a minimal influence of individual studies on the overall proportion effect estimate (Fig 4c). These results show a significant proportion of insomnia among EVD survivors.

Discussion

The objective of this study was to provide pooled prevalence estimates of some common mental health problems amid health disaster events in West-Africa. Generally, our meta-analysis revealed findings regarding the presence of symptoms of anxiety, depression, and insomnia among Ebola virus disease survivors. Of the 13 studies involving 3042 Ebola virus disease survivors, a significant percentage of them reported anxiety, depression and insomnia symptoms. We found an estimated anxiety prevalence of 14% (99% CI: 0.05–0.30) among EVD survivors. Also, a significant proportion, 15% (99% CI: 0.11–0.21) of the survivors reported depression. However, there was a higher prevalence of insomnia, 22% (99% CI: 0.13–0.36) among EVD survivors. Our results are slightly higher than what was reported in a recently published three-country study that found a 10.7%, 9.9% and 4.2% prevalence in anxiety among Ebola survivors in Sierra Leone, Liberia and Guinea respectively [53]. It is interesting to note that, studies that are restricted to only Ebola survivors tend to report lower estimates of anxiety, depression and insomnia compared to those conducted among the general population. In contrast to what we found, previous studies that reported on the mental health consequence of post-disaster occurrences in Sierra Leone showed a higher anxiety prevalence of 48% (95% CI: 46.8% to 50.0%) among the general population [54,55]. Although the reasons for the low prevalence estimates in these symptoms specifically among Ebola survivors are unclear, at the population level, researchers attributed the higher prevalence of people with mental health problems to region of residence, experiences with Ebola and perceived Ebola threat or knowing someone quarantined for Ebola [54,55].

Also, the findings of other studies support that there is a high prevalence of depression and reduced quality of life among survivors of EVD [23,56]. However, in contrast to the global estimate of 21% of depression among EVD survivors [23], our study only revealed a 15% pooled prevalence. We believe that the difference in proportions estimated could be due to the fewer number of studies used and our restriction to only studies in the African region. Similarly, with regards to insomnia, our prevalence estimates of 22% are lesser than a global estimate of 34% among EVD survivors [23]. We also attribute the differences in estimates to our regional restriction and fewer number of studies used in this meta-analysis. Taking the preceding into perspective, we believe these findings should be interpreted and applied with the needed caution.

Several studies have shown similarities between mental health outcomes among survivors of infectious disease outbreaks (e.g. the 2003 severe acute respiratory syndrome (SARS); 2009 novel influenza A (H1N1) pandemic; human immunodeficiency viruses (HIV/AIDS)) and other types of natural disasters including mass conflicts and displacement of people [57–59]. Accordingly, our study reveals, survivors of regional and global health crises such as EVD survivors are at an increased risk of symptoms of anxiety, depression, and insomnia. There is thus the need to scale up mental health services as a joint effort in combination with the normal biomedical health responses when faced with health disasters. Such coordinated efforts will demand comprehensive collaboration between governments, health professionals, donors, civil society, communities, and patients and their families to cater for vulnerable populations such as EVD survivors as recommended by the WHO Mental Health Gap Action Programme [60].

Strengths and limitations of the study

A significant strength of this study is that, to the best of the authors’ knowledge, this review is the first meta-analysis review of its kind to have estimated the prevalence of anxiety, depression and insomnia symptoms among EVD survivors in West Africa. Also, the relatively large sample size for our pooled estimates provides some significant power to our prevalence effect estimates. However, we acknowledge some limitations of our study.

First, although the recent outbreak has provided many new insights and a lot of new data, methodologically sound studies are still scarce. For instance, a majority of the studies used a cross-sectional design which prevents the establishment of a cause-effect relationship between EVD and anxiety, depression and insomnia symptoms. Thus, the heterogeneity in our proportion estimates of anxiety, depression and insomnia symptoms may simply be due to differences in the study designs, data quality, and/or demographic variations in various study samples. Also, the higher number of cross-sectional studies affects our ability to draw cause-effect conclusions from our results. Secondly, as indicated, most of the articles we assessed did not compare EVD survivors to a control group. Therefore, we could not calculate measures of association (relative risks, odds ratios, etc.) between EVD and anxiety, depression and insomnia among survivors. Unfortunately, we contacted the authors but were unable to obtain the required data from the respective authors of the various studies assessed. Thus, we report our findings tentatively and advise readers to do likewise. We recommend that studies with more robust designs (e.g. cohort studies and case-control studies) should be conducted to establish the association between EVD and anxiety, depression and insomnia. Thirdly, there were no data on the severity of Ebola illness in all the papers assessed. Thus, our study could not distinguish between individuals who have these symptoms from others who do not. Finally, there were also differences in whether symptoms were based on clinical diagnosis or self-report. The mode of assessment of EVD patients’ mental health symptoms was not uniform. While some studies reported the use of a standardized questionnaire, others reported medical reports as well as clinical assessment. The differences in measurement instruments and concerns about the quality of data prevent comparability of the studies we assessed.

Conclusion

Findings from our review show that anxiety, depression and insomnia symptoms seem to be prevalent and widespread among EVD survivors. By highlighting the prevalence of mental health needs among EVD survivors, we hope this evidence supports policy and clinical efforts in allocating appropriate resources to mitigate the mental health impacts among survivors, families, and frontline workers during health disaster events (e.g. EVD and the current SARS-CoV-19 pandemic). We believe that providing program interventions, including organized mental health outreach activities, will go a long way to help EVD survivors navigate anxiety, depression and insomnia symptoms and improve their quality of life. However, similar to current mental health intervention efforts for veterans, a comprehensive and collaborative effort between relevant stakeholders is needed to achieve a successful complementary biomedical and mental health approach to health crisis survivors’ in the future. Currently, few robust longitudinal studies examine the links between EVD and anxiety, depression and insomnia among survivors especially in Africa. Thus, we recommend robust longitudinal studies, including cohort and case-control studies, to help establish causal associations between EVD and anxiety, depression and insomnia as well as post traumatic stress disorder (PTSD).

Supporting information

S1 Checklist. PRISMA 2009 checklist.

(DOC)

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S1 File

(XLSX)

Click here for additional data file.^{(12.3KB, xlsx)}

Acknowledgments

We acknowledge the contribution of earlier researchers and Ebola virus disease survivors for producing the data in this less researched area that we pooled and re-analysed in our present study.

Data Availability

All relevant data are within the manuscript and its Supporting information files.

Funding Statement

The author(s) received no specific funding for this work.

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PLoS One. doi: 10.1371/journal.pone.0246515.r001

Decision Letter 0

John Schieffelin

15 Jul 2020

PONE-D-20-14937

Prevalence of posttraumatic stress disorder (PTSD) symptoms among Ebola survivors in Africa: a meta-analysis

PLOS ONE

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Reviewer #1: Partly

Reviewer #2: Yes

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Reviewer #1: Yes

Reviewer #2: I Don't Know

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Reviewer #2: Yes

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Reviewer #2: Yes

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5. Review Comments to the Author

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Reviewer #1: This meta-analysis investigated the prevalence of PTSD symptoms among survivors of the 2014–2016 Ebola virus disease in the West African sub-region. Documenting the psychological impact of this mass public health crisis is important in order to inform both prevention and mitigation efforts as new crises emerge. A summary of studies of Ebola survivors is timely but several concerns need to be addressed for this paper to be a worthwhile contribution.

First, this should not be titled and described as a study of PTSD symptoms. Anxiety and depression are not specific PTSD symptoms, although some PTSD symptoms are similar to them (e.g.,. hyperarousal, negative mood). PTSD may involve insomnia but not all insomnia is trauma-related. It may be that experiencing Ebol;a was traumatizing, but without evidence linking the symptoms to Ebola-related experiences these cannot be assumed to be PTSD, they may be due to other stressors or pre-existing conditions, for example. The study should be described as assessing anxiety, depression, and insomnia symptoms, and the possible link to traumatization can be noted but not assumed. The lengthy and very basic description of PTSD should be deleted or greatly shortened.

Second, how does this study add new information beyond that reported in other reviews? Is it the first to bring together these or similar studies? IF not, what new information does it provide other than showing that prevalence estimates of the target symptoms are generally consistent across nationalities?

The absence of any comparison to estimates of the target conditions is understandable given that most of the studies did not include non-Ebola control groups. However, whether the prevalence estimates are clinically significant needs to be justified by contrasting the pooled estimates with prevalence data from community epidemiological studies. The prevalence of estimates for symptoms of anxiety (14%; 99% CI: 0.05–0.30), depression (15%; 99% CI: 0.11–0.21), and insomnia (22%; 99% CI: 0.13–0.36) are not clearly higher than estimates from other population surveys, making the authors' conclusion that "a significant amount of EVD survivors are struggling with common PTSD symptoms" unjustified.

Additionally, information is needed about how each of the conditions was operationalized in the various studies. Some stuidies used questionnaires: how were "anxiety" "depression" and "insomnia" determined to be present and clinically significant in the different studies? If symptom levels with a cutoff was used, was this based on relevant validation evidence? Other studies relied on medical reports: what was reported (diagnoses? impressions?) and what evidence was provided that the report yielded a valid classification of clinically significant symptoms?

The authors state that there was no publication bias, but how they determined this needs to be explained carefully.

Also, a major possible bias is the selection of participants. How did the studies demonstrate that their samples were representative of the larger group of Ebola survivors in their setting? If the samples are not clearly representative the findings are of limited value.

Were there no data on the severity of Ebola illness? This may distinguish individuals who have these symptoms from others who do not. If this was not reported it should be noted as a limitation.

Was gender not reported? Comparing men vs. women would add to the usefulness of the results.

Statements that describe the study or its findings in congratulatory manner should be deleted (e.g., "exciting" findings).

Reviewer #2: This study presents the results of a meta-analysis of PTSD symptoms among EVD survivors in sub-Saharan Africa. This study is indeed timely given the current COVID pandemic, and as the authors note, a lack of attention in both science and practice on the mental health sequelae of infectious diseases. Overall the article is well organized and well written, and I believe is poised to make an important contribution to the literature. I have a number of suggestions to improve the article, listed below.

Abstract

I would avoid beginning the abstract with a statement of the study’s timeliness. It would be better to lead with, “During health disaster events….”

I am not that familiar with methods in meta analyses, but I am accustomed to seeing effect sizes reported. In addition to prevalence estimates, is it possible to report effect sizes?

Introduction

The literature reviewed in this section is thorough and highlights the problems of mental health care particularly in LMICs. The section could be better organized to make it easier for the reader to digest, either through (a) more effective use of introductory sentences in each paragraph, or (b) the use of headings and subheadings.

The word “unfortunately” is used too much – in particular, see the beginning sentences on p. 10 and p. 11

Methods

This section is clear and succinct. For study inclusion and exclusion criteria, it would be helpful to know the number of studies included and excluded per criterion – if possible, within the flow chart depicted on p. 13.

Results

The information provided in the first paragraph is redundant with information already provided in the Methods section.

Discussion

The first paragraph basically repeats earlier information – I would advise starting this section with the main contribution of this study to existing literature.

On p. 22, replace with word “exciting” with a word more appropriate to the situation: “Generally, our meta-analysis revealed exciting findings….”

Also, on p. 22, the authors report a total of 3,042 EVD survivors included in the study. Are the authors sure that the various studies all used different samples? Or could there be overlap across studies in terms of participants?

In the Discussion section, please give some thought as to potential mechanisms behind the various prevalence rates presented. For example, why might insomnia have a higher prevalence than anxiety and depression? Also, the prevalence rates in the current study are much lower across the board compared to individual studies. Please go into some detail as to why the meta-analysis shows lower prevalence rates.

**********

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Reviewer #1: No

Reviewer #2: Yes: Thomas M Crea

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PLoS One. 2021 Feb 5;16(2):e0246515. doi: 10.1371/journal.pone.0246515.r002

Author response to Decision Letter 0

3 Oct 2020

Dear John Schieffelin,

Re: Response to Reviewer’s Comments

We appreciate the reviewer’s suggestions and comments on our manuscript and have carefully gone through the details and made sure the revised manuscript fully addresses the editor’s and reviewer’s comments.

Below we have outlined our responses in the attached Response to Review Comments.

The authors thank the reviewer for bringing these matters to our attention, we hope we have successfully addressed them.

Furthermore as a result of those comments we have substantially revised the whole manuscript.

Response to Review Comments

Specifically, the Reviewer made the following comments and we have made the following changes to the manuscript: (full details of the Reviewer’s comments are shown below):

Reviewer 1

Reviewer Comment 1.

First, this should not be titled and described as a study of PTSD symptoms. Anxiety and depression are not specific PTSD symptoms, although some PTSD symptoms are similar to them (e.g.,. hyperarousal, negative mood). PTSD may involve insomnia but not all insomnia is trauma related. It may be that experiencing Ebol;a was traumatizing, but without evidence linking the symptoms to Ebola-related experiences these cannot be assumed to be PTSD, they may be due to other stressors or pre-existing conditions, for example. The study should be described as assessing anxiety, depression, and insomnia symptoms, and the possible link to traumatization can be noted but not assumed. The lengthy and very basic description of PTSD should be deleted or greatly shortened.

Response

We thank the reviewer for this observation:

We have accepted the suggestion and adopted a new title which now reads;

“Assessing anxiety, depression, and insomnia symptoms among Ebola survivors in Africa: a meta-analysis”.

We have also accepted the recommendation to delete the definition of post-traumatic stress disorder (PTSD). This has been deleted from the document.

Reviewer Comment 2

“Second, how does this study add new information beyond that reported in other reviews? Is it the first to bring together these or similar studies? IF not, what new information does it provide other than showing that prevalence estimates of the target symptoms are generally consistent across nationalities?”

Response

We thank the reviewer for this observation:

Few studies (2) have qualitatively assessed the psychological and neuropsychological consequences as well as lived experiences of Ebola survivors. To the authors’ knowledge, no study has quantitatively estimated the prevalence of anxiety, depressive symptoms, and insomnia among Ebola survivors. Accurate estimates are required for informed policy planning. This is stated in our manuscript on page 3 line 10-18 as;

“Currently, the majority of existing reviews have been qualitative assessments of psychological and neuropsychological consequences, lived experiences and coping strategies of Ebola disease among survivors [23,24]. Also, there appears to be non-existing meta-analysis evidence on the prevalence of anxiety, depression and insomnia symptoms as mental health burden among Ebola survivors in the affected countries in Africa”. Thus, this meta-analysis presents a quantitative estimate of the prevalence of the above symptoms among EVD survivors. Providing this evidence could support clinical and policy efforts to improve post-health crisis interventions and resources allocation to mitigate the mental health impacts for survivors, families, and frontline workers….”

Reviewer comment 3

“The absence of any comparison to estimates of the target conditions is understandable given that most of the studies did not include non-Ebola control groups. However, whether the prevalence estimates are clinically significant needs to be justified by contrasting the pooled estimates with prevalence data from community epidemiological studies. The prevalence of estimates for symptoms of anxiety (14%; 99% CI: 0.05–0.30), depression (15%; 99% CI: 0.11–0.21), and insomnia (22%; 99% CI: 0.13–0.36) are not clearly higher than estimates from other population surveys, making the authors' conclusion that "a significant amount of EVD survivors are struggling with common PTSD symptoms" unjustified”.

We acknowledge that, prevalence estimates in the general population surveys may be higher than those among only Ebola virus disease survivors. We also note that our restriction of this study to only survivors of Ebola diseases might have led to underreporting compared to the general population. Our findings are similar to a recently published paper. We have duly stated that in our manuscript which now reads;

“Our results are slightly higher than what was reported in a recently published three-country study that found a 10.7%, 9.9% and 4.2% prevalence in anxiety among Ebola survivors in Sierra Leone, Liberia and Guinea respectively [60]. It is interesting to note that, studies that are restricted to only Ebola survivors turn to report lower estimates of anxiety, depression and insomnia compared to those conducted among the general population. In contrast to what we found, previous studies that reported on the mental health consequence of post-disaster occurrences in Sierra Leone showed a higher anxiety prevalence of 48% (95% CI: 46.8% to 50.0%) among the general population [53, 54]. Although the reasons for the low prevalence estimates in these symptoms specifically among Ebola survivors are unclear, at the population level, researchers attributed the higher prevalence of people with mental health problems to region of residence, experiences with Ebola and perceived Ebola threat or knowing someone quarantined for Ebola [53, 54]”.

Reviewer comment 4

“Additionally, information is needed about how each of the conditions was operationalized in the various studies. Some studies used questionnaires: how were "anxiety" "depression" and "insomnia" determined to be present and clinically significant in the different studies? If symptom levels with a cut-off was used, was this based on relevant validation evidence? Other studies relied on medical reports: what was reported (diagnoses? impressions?) and what evidence was provided that the report yielded a valid classification of clinically significant symptoms?”

Response

We also note this observation.

In Table 1 of our study, we provide a list of the assessment instruments that were used by each study to measure the health outcomes of interest that our paper focused on. Several of the studies relied on standardized questionnaires and clinical assessments to provide diagnosis whereas others used medical reports. Comprehensive details of these measures are provided in the methods section of each paper we used in this meta-analysis. However, some of the papers used did not provide details of their clinical diagnostic criteria and the clinical classification standards used to conduct their assessments of the clinical conditions we focused on. Therefore, our inability to access this information limits our ability to comment on this comment as we were unable to access this information from the authors we contacted. We also recognize that this is a further limitation of our study.

Reviewer comment 5

The authors state that there was no publication bias, but how they determined this needs to be explained carefully.

Response

We thank the reviewer for the observations.

Indeed, we recognize the need to ensure our estimates reflect accurately on the full spectrum of Ebola studies regarding the three conditions we focused on. Therefore, we have provided a full description of how we assessed publication bias in the data analysis and synthesis section of our paper. We relied on several statistical techniques to determine publication bias including funnel plots based on standard errors and the Eagger unweighted regression test (which is deemed suitable for meta-analysis using a small number of studies, less than 25 studies). Related to this, we also used the Leave-one-out diagnostic test to further confirm the effect of each study on the overall mean and estimate in order to control for overly influential studies in the meta-analysis as multiple studies conducted within the same country could have used overlapping samples.

Reviewer comment 6

Response

We thank the reviewer for the observation.

More information on the details of each article included in this study can be found in Table 1, of our paper. It was our general observation that these studies each used a fairly representative sample size from the general Ebola survivor population within each respective study country. Several of the papers provided comprehensive summary statistics of the total Ebola survivors’ population in the area studied and the total number of that population used in their given studies. This information can be found in the methods section of each study. However, as our study mainly focused on the three conditions (i.e. anxiety, insomnia, and depression), we relied on the section of the total sample size for whom complete data on proportions was provided relating to these three conditions.

Reviewer comment 7

Were there no data on the severity of Ebola illness? This may distinguish individuals who have these symptoms from others who do not. If this was not reported it should be noted as a limitation.

Response

We acknowledge this limitation in our manuscript in page 15, lines 26-28 and it now reads;

“Thirdly, there were no data on the severity of Ebola illness in all the papers assessed. Thus, our study could not distinguish between individuals who have these symptoms from others who do not….”

Reviewer comment 8

Was gender not reported? Comparing men vs. women would add to the usefulness of the results.

Response

We thank the reviewer for the observation.

Gender was not consistently reported across board in the papers analysed. We could not do sub-analysis by gender, because it will not give a fair representation of the papers and may affect the reliability of our results. Our initial goal was to include sub-analysis to the paper based on different demographic variables. However, there was limited data provided on the several demographic variables related to anxiety, depression, and insomnia, and we were unable to obtain the raw data from the authors of the included studies that we reached out to. In addition, the small number of studies under each analysis stratum would not permit any meaningful sub-group analysis. Evidence of these emails can be provided should there be a request. This has been stated in our manuscript in page 15, lines 22,23 as a limitation of our study.

Reviewer comment 9

Statements that describe the study or its findings in congratulatory manner should be deleted (e.g., "exciting" findings).

Response

We thank the reviewer for the observation

The word “exciting” has been deleted and the sentence now reads;

“Generally, our meta-analysis revealed findings regarding the presence of symptoms of anxiety, depression, and insomnia among Ebola virus disease survivors….”

Reviewer 2

Reviewer comment 1

I would avoid beginning the abstract with a statement of the study’s timeliness. It would be better to lead with, “During health disaster events….”

Response

The authors thank the reviewer for the observation

The background section of the abstract has been reworded and it now reads;

“During health disaster events such as the current devastating havoc being inflicted on countries globally by the SARS-CoV-2 pandemic, mental health problems among survivors and frontline workers are likely….”

Reviewer comment 2

I am not that familiar with methods in meta analyses, but I am accustomed to seeing effect sizes reported. In addition to prevalence estimates, is it possible to report effect sizes?

Response

We appreciate the reviewer’s recommendation and have adopted it and added effect estimates to our results section in the abstract which now reads;

“Effect estimates ranging from (0.13; 99% CI: 0.05, 0.28) through to (0.11; 99% CI: 0.05–0.22), (0.15; 99% CI: 0.09–0.25) through to (0.13; 99% CI: 0.08–0.21) and (0.23; 99% CI: 0.11–0.41) to (0.23; 99% CI: 0.11–0.41) were respectively reported for anxiety, depression and insomnia symptoms…”

Reviewer comment 3

Response

We have accepted the recommendation of the reviewer and used introductory sentences such as in addition, also, however, therefore, currently etc. to link various paragraphs.

Reviewer comment 4

The word “unfortunately” is used too much – in particular, see the beginning sentences on p. 10 and p. 11.

Response

We appreciate the reviewer’s observation

The usage of the word “unfortunately” has been reduced to two and replaced with words such as “however”, “therefore” etc.

Reviewer comment 5

Response

We followed standard recommended practice of inclusion and exclusion criteria in our article screening process using the flow chart. It should however be noted that the number of studies included and excluded per criterion in this study can be found under search results in page 5.

Reviewer comment 6

The information provided in the first paragraph is redundant with information already provided in the Methods section.

Response

We thank the reviewer for this observation.

We have deleted the redundant information from the first paragraph of the results section and the paragraph now reads;

“A total of 13 remaining articles were included in the meta-analysis [40-52]. Table 1 shows a detailed summary of the study attributes and data on the characteristics of the reviewed articles. Data were extracted based on the following features: country, design, sample, sex, age, follow-up period, presence of anxiety, depression, and insomnia. We considered the quality of the studies reviewed as high as there was no observed evidence of any publication bias….”

Reviewer comment 7

The first paragraph basically repeats earlier information – I would advise starting this section with the main contribution of this study to existing literature.

Response

We again thank the reviewer for this observation.

We have deleted the redundant information from the first paragraph of the discussion section and the paragraph now reads;

“The objective of this study was to provide pooled prevalence estimates of some common mental health problems amid health disaster events in West-Africa. Generally, our meta-analysis revealed findings regarding the presence of symptoms of anxiety, depression, and insomnia among Ebola virus disease survivors….”

Reviewer comment 8

On p. 22, replace with word “exciting” with a word more appropriate to the situation: “Generally, our meta-analysis revealed exciting findings….”

We essentially dealt with this point under response 9 to Reviewer#1. We repeat it here

We thank the reviewer for the observation

The word “exciting” has been deleted and the sentence now reads;

“Generally, our meta-analysis revealed findings regarding the presence of symptoms of anxiety, depression, and insomnia among Ebola virus disease survivors…”

Reviewer comment 9

Response

We are grateful to the reviewer for this observation. Indeed, as a meta-analysis study, we were limited to available studies that were conducted in specific countries where the Ebola virus was peculiar to. In this regard, multiple studies using different methods were conducted on the Ebola virus within some countries by the different researchers. Although the authors admit that there might be an overlap across studies in terms of participants, we undertook several statistical measures to control for some amount of this overlap including considering only raw frequencies of reported symptoms of anxiety, depression and insomnia to estimate their prevalence. Also, as heteroscedasticity is a major concern when samples are assumed to be related, we undertook several statistical measures including using the Q-statistic (X2) and SerSimonian and Laird I2 statistic were used to determine heterogeneity across the various studies used. In addition, the Leave-one-out statistical technique was used to identify the effect of each study on the overall mean and estimate for the observed summary proportions. This allowed us to control for outlying studies that could have occurred due to having correlated samples. These techniques are discussed in full in the Data analysis and synthesis section of our study.

Reviewer comment 10

We essentially dealt with this point under response 3 to Reviewer#1. We repeat it here

Our results are slightly higher than what was reported in a recently published three-country study that found a 10.7%, 9.9% and 4.2% prevalence in anxiety among Ebola survivors in Sierra Leone, Liberia and Guinea respectively [60]. It is interesting to note that, studies that are restricted to only Ebola survivors turn to report lower estimates of anxiety, depression and insomnia compared to those conducted among the general population. In contrast to what we found, previous studies that reported on the mental health consequence of post-disaster occurrences in Sierra Leone showed a higher anxiety prevalence of 48% (95% CI: 46.8% to 50.0%) among the general population [53, 54]. Although the reasons for the low prevalence estimates in these symptoms specifically among Ebola survivors are unclear, at the population level, researchers attributed the higher population of prevalence the mental health problems to region of residence, experiences with Ebola and perceived Ebola threat or knowing someone quarantined for Ebola [53, 54].

The authors thank the reviewers for bringing these matters to our attention, we hope we have successfully addressed them.

PLoS One. doi: 10.1371/journal.pone.0246515.r003

Decision Letter 1

John Schieffelin

11 Nov 2020

PONE-D-20-14937R1

Assessing anxiety, depression and insomnia symptoms among Ebola survivors in Africa: a meta-analysis

PLOS ONE

Dear Dr. Mengesha,

Please submit your revised manuscript by Dec 26 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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We look forward to receiving your revised manuscript.

Kind regards,

John Schieffelin, MD

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Reviewer #1: Very thoughtful and responsive revision, the paper now is a solid contribution to the field. I have a few additional revisions to suggest:

1. Table 1: delete "(years)" from the header (several entries are in months)

2. Results: Explain briefly how the studies confirmed the past diagnosis of Ebola (apparently this was done by medical records in some cases and self-report in others) and consider examining whether the findings differ based on whether the health outcomes were assessed by medical records versus self-report (it appears from the sensitivity analyses that this did not make a difference, but it would be good to be explicit about that).

3. I don't think that the lower prevalence estimates in this meta-analysis are due to a "fewer number of studies used" -- a more likely reason is that this meta-analysis included only studies that identified clinically-significant anxiety, depression, and insomnia symptoms where the prior reviews may have included estimates based on symptoms that were mild as well.

4. Consider the possibility that unlike surviving a mass disaster that involved intentional harm (e.g., war) or that destroyed entire communities (like natural or humanmade disasters), surviving Ebola may not cause a chronic emotional injury (except for persons who lost loved ones or experienced extreme suffering and feared they would die), and those who do survive may be relatively physically and emotionally resilient. This could explain the relatively normative prevalence estimates.

5. The statement that this "study reveals, survivors ... are at increased risk of symptoms ..." is not accurate. The findings suggest that EVD survivors may experience problems with anxiety, depression, and insomnia, but not that they are at increased risk because the prevalence estimates are not clearly higher than those for general community samples in Africa (or other parts of the world). The findings do suggest that research is needed to determine what risk factors (e.g., severity of the disease, loss of loved ones, fear of dying) distinguish EVD survivors who have these problems from those who do not. If risk factors are identified, then prevention and treatment can be targeted to address them, which is more feasible and cost-effective than a universal program to prevent mental health problems for all EVD survivors (most of whom apparently are not experiencing problematic anxiety, depression, or insomnia).

Reviewer #2: All of my comments have been adequately addressed. Thanks to the authors for their responsiveness. The article will make a positive contribution to the literature on Ebola and mental health.

**********

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If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: Yes: Thomas M. Crea

PLoS One. 2021 Feb 5;16(2):e0246515. doi: 10.1371/journal.pone.0246515.r004

Author response to Decision Letter 1

10 Dec 2020

Dear John Schieffelin,

Re: Response to Reviewer’s Comments

Below we have outlined our responses in the attached Response to Review Comments.

The authors thank the reviewer for bringing these matters to our attention, we hope we have successfully addressed them.

Furthermore as a result of those comments we have substantially revised the whole manuscript.

Response to Review Comments

Specifically, the Reviewer made the following comments and we have made the following changes to the manuscript: (full details of the Reviewer’s comments are shown below):

Reviewer 1

Opening comment

Very thoughtful and responsive revision, the paper now is a solid contribution to the field. I have a few additional revisions to suggest

Response

The authors are grateful to the reviewer for the kind words and his/her thought-provoking comments that have contributed towards improving the quality of this manuscript.

Reviewer Comment 1.

Table 1: delete "(years)" from the header (several entries are in months)

Response

We thank the reviewer for this observation:

We have accepted the suggestion and deleted years from the header in table 1.

Reviewer Comment 2

“Results: Explain briefly how the studies confirmed the past diagnosis of Ebola (apparently this was done by medical records in some cases and self-report in others) and consider examining whether the findings differ based on whether the health outcomes were assessed by medical records versus self-report (it appears from the sensitivity analyses that this did not make a difference, but it would be good to be explicit about that)”.

Response

We thank the reviewer for this observation:

“We agree with the suggestion to explicitly confirm if any differences existed in the findings based on the assessment of health outcome of interest. However, while we acknowledge strongly that there is a need for further sub-analysis, we would like to kindly mention that all the studies included in the meta-analysis confirmed an Ebola diagnosis using medically approved clinical tests which were not included in this meta-analysis as this topic was beyond the scope of the paper. We also note that these self-reports and medical records were mainly used to examine patients’ mental health states including the presence or absence of insomnia, depression, and anxiety. Moreover, as mentioned in our earlier response, we were unable to conduct further sub-analysis on covariates including the assessment of health outcomes because of the small sample size of articles included in the meta-analysis. We have now included this as a potential limitation in our paper and a recommendation for future studies on this or similar topics.”

Reviewer comment 3

“I don't think that the lower prevalence estimates in this meta-analysis are due to a "fewer number of studies used" -- a more likely reason is that this meta-analysis included only studies that identified clinically-significant anxiety, depression, and insomnia symptoms where the prior reviews may have included estimates based on symptoms that were mild as well”.

Response

We accept the recommendation of the reviewer and have incorporated the comment into the manuscript and it now reads;

“We believe that a more likely reason for the differences in the estimated proportions is that this meta-analysis included only studies that identified clinically-significant anxiety, depression, and insomnia symptoms where the prior reviews may have included estimates based on symptoms that were mild as well”.

Reviewer comment 4

“Consider the possibility that unlike surviving a mass disaster that involved intentional harm (e.g., war) or that destroyed entire communities (like natural or humanmade disasters), surviving Ebola may not cause a chronic emotional injury (except for persons who lost loved ones or experienced extreme suffering and feared they would die), and those who do survive may be relatively physically and emotionally resilient. This could explain the relatively normative prevalence estimates”

Response

We accept the recommendation of the reviewer and have incorporated the comment into the manuscript and it now reads;

“A possible explanation to our findings is that unlike surviving a mass disaster that involved intentional harm (e.g., war) or that destroyed entire communities (like natural or humanmade disasters), surviving Ebola may not cause a chronic emotional injury (except for persons who lost loved ones or experienced extreme suffering and feared they would die), and those who do survive may be relatively physically and emotionally resilient.”

Reviewer comment 5

“The statement that this "study reveals, survivors ... are at increased risk of symptoms ..." is not accurate. The findings suggest that EVD survivors may experience problems with anxiety, depression, and insomnia, but not that they are at increased risk because the prevalence estimates are not clearly higher than those for general community samples in Africa (or other parts of the world). The findings do suggest that research is needed to determine what risk factors (e.g., severity of the disease, loss of loved ones, fear of dying) distinguish EVD survivors who have these problems from those who do not. If risk factors are identified, then prevention and treatment can be targeted to address them, which is more feasible and cost-effective than a universal program to prevent mental health problems for all EVD survivors (most of whom apparently are not experiencing problematic anxiety, depression, or insomnia)”.

Response

We thank the reviewer for the suggestion. This has been incorporated into the manuscript and it now reads;

“Accordingly, our findings suggest that EVD survivors may experience problems with anxiety, depression, and insomnia. The findings also suggest that research is needed to determine what risk factors (e.g., severity of the disease, loss of loved ones, fear of dying) distinguish EVD survivors who have these problems from those who do not. If such risk factors are identified, then prevention and treatment can be targeted to address them, which is more feasible and cost-effective than a universal program to prevent mental health problems for all EVD survivors (most of whom apparently are not experiencing problematic anxiety, depression, or insomnia). Such coordinated targeted interventions will demand comprehensive collaboration between governments, health professionals, donors, civil society, communities, and patients and their families to cater for vulnerable populations such as EVD survivors as recommended by the WHO Mental Health Gap Action Programme [59]”.

Reviewer 2

Reviewer comment 1

All of my comments have been adequately addressed. Thanks to the authors for their responsiveness. The article will make a positive contribution to the literature on Ebola and mental health

Response

The authors are grateful to the reviewer for the kind words and thankful for him/her agreeing to review our manuscript that will contribute to the literature on Ebola and mental health

PLoS One. doi: 10.1371/journal.pone.0246515.r005

Decision Letter 2

John Schieffelin

21 Jan 2021

Assessing anxiety, depression and insomnia symptoms among Ebola survivors in Africa: a meta-analysis

PONE-D-20-14937R2

Dear Dr. Mengesha,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

John Schieffelin, MD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

Reviewer #1: Yes

Reviewer #2: (No Response)

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

Reviewer #1: Yes

Reviewer #2: (No Response)

**********

6. Review Comments to the Author

Reviewer #1: Excellent revision and solid contribution to the research literature on an important topic.

Reviewer #2: All of my comments have been adequately addressed. Thanks to the authors for their

responsiveness. The article will make a positive contribution to the literature on Ebola

and mental health.

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: No

PLoS One. doi: 10.1371/journal.pone.0246515.r006

Acceptance letter

John Schieffelin

26 Jan 2021

PONE-D-20-14937R2

Assessing anxiety, depression and insomnia symptoms among Ebola survivors in Africa: a meta-analysis

Dear Dr. Mengesha:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

S1 Checklist. PRISMA 2009 checklist.

(DOC)

Click here for additional data file.^{(63KB, doc)}

S1 File

(XLSX)

Click here for additional data file.^{(12.3KB, xlsx)}

Data Availability Statement

All relevant data are within the manuscript and its Supporting information files.

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Assessing anxiety, depression and insomnia symptoms among Ebola survivors in Africa: A meta-analysis

Jeremiah W Acharibasam

Batholomew Chireh

Hayelom G Menegesha

Roles

Abstract

Background

Methods

Results

Conclusion

Introduction

Methods

Search strategy

Fig 1. PRISMA flow diagram-Ebola and anxiety, depression and insomnia symptoms.

Inclusion/Exclusion criteria

Search results

Table 1. Summary of studies’ attributes.

Data collection and extraction

Data analysis and synthesis

Results

Ebola and anxiety

Fig 2.

Ebola and depression

Fig 3.

Ebola and insomnia

Fig 4.

Discussion

Strengths and limitations of the study

Conclusion

Supporting information

Acknowledgments

Data Availability

Funding Statement

References

Decision Letter 0

John Schieffelin

Roles

Author response to Decision Letter 0

Decision Letter 1

John Schieffelin

Roles

Author response to Decision Letter 1

Decision Letter 2

John Schieffelin

Roles

Acceptance letter

John Schieffelin

Roles

Associated Data

Supplementary Materials

Data Availability Statement

ACTIONS

PERMALINK

RESOURCES

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