Skip to main content
NCBI home page
PLOS One logoLink to PLOS One
. 2024 Jul 1;19(7):e0306245. doi: 10.1371/journal.pone.0306245

Risk factors for toxoplasmosis in people living with HIV in the Asia-Pacific region

Ki Hyun Lee 1, Awachana Jiamsakul 2, Sasisopin Kiertiburanakul 3, Rohidas Borse 4, Vohith Khol 5, Evy Yunihastuti 6, Iskandar Azwa 7, I Ketut Agus Somia 8, Romanee Chaiwarith 9, Thach Ngoc Pham 10, Suwimon Khusuwan 11, Cuong Duy Do 12, Nagalingeswaran Kumarasamy 13, Yasmin Gani 14, Rossana Ditangco 15, Oon Tek Ng 16, Sanjay Pujari 17, Man Po Lee 18, Anchalee Avihingsanon 19, Hsin-Pai Chen 20, Fujie Zhang 21, Junko Tanuma 22, Jeremy Ross 23, Jun Yong Choi 1,*
Editor: Masoud Foroutan24
PMCID: PMC11216616  PMID: 38950027

Abstract

Introduction

Toxoplasma gondii can cause symptomatic toxoplasmosis in immunodeficient hosts, including in people living with human immunodeficiency virus (PLWH), mainly because of the reactivation of latent infection. We assessed the prevalence of toxoplasmosis and its associated risk factors in PLWH in the Asia-Pacific region using data from the TREAT Asia Human Immunodeficiency Virus (HIV) Observational Database (TAHOD) of the International Epidemiology Databases to Evaluate AIDS (IeDEA) Asia-Pacific.

Methods

This study included both retrospective and prospective cases of toxoplasmosis reported between 1997 and 2020. A matched case-control method was employed, where PLWH diagnosed with toxoplasmosis (cases) were each matched to two PLWH without a toxoplasmosis diagnosis (controls) from the same site. Sites without toxoplasmosis were excluded. Risk factors for toxoplasmosis were analyzed using conditional logistic regression.

Results

A total of 269/9576 (2.8%) PLWH were diagnosed with toxoplasmosis in 19 TAHOD sites. Of these, 227 (84%) were reported retrospectively and 42 (16%) were prospective diagnoses after cohort enrollment. At the time of toxoplasmosis diagnosis, the median age was 33 years (interquartile range 28–38), and 80% participants were male, 75% were not on antiretroviral therapy (ART). Excluding 63 out of 269 people without CD4 values, 192 (93.2%) had CD4 ≤200 cells/μL and 162 (78.6%) had CD4 ≤100 cells/μL. By employing 538 matched controls, we found that factors associated with toxoplasmosis included abstaining from ART (odds ratio [OR] 3.62, 95% CI 1.81–7.24), in comparison to receiving nucleoside reverse transcriptase inhibitors plus non-nucleoside reverse transcriptase inhibitors, HIV exposure through injection drug use (OR 2.27, 95% CI 1.15–4.47) as opposed to engaging in heterosexual intercourse and testing positive for hepatitis B virus surface antigen (OR 3.19, 95% CI 1.41–7.21). Toxoplasmosis was less likely with increasing CD4 counts (51–100 cells/μL: OR 0.41, 95% CI 0.18–0.96; 101–200 cells/μL: OR 0.14, 95% CI 0.06–0.34; >200 cells/μL: OR 0.02, 95% CI 0.01–0.06), when compared to CD4 ≤50 cells/μL. Moreover, the use of prophylactic cotrimoxazole was not associated with toxoplasmosis.

Conclusions

Symptomatic toxoplasmosis is rare but still occurs in PLWH in the Asia-Pacific region, especially in the context of delayed diagnosis, causing advanced HIV disease. Immune reconstitution through early diagnosis and ART administration remains a priority in Asian PLWH.

Introduction

The obligate intracellular protozoan parasite Toxoplasma gondii is a prevalent pathogen worldwide [1]. Because significant overt infections are rare, the extent of the actual Toxoplasma infection is mainly estimated based on serological test results. Seroprevalence varies depending on the region, environment, cultural habits, and lifestyle, with seropositivity rates exceeding 70% in some areas [2].

Toxoplasma infection rarely appears as an overt infection despite its high seropositivity. However, in people living with human immunodeficiency virus (PLWH) with low CD4+ T lymphocytes, toxoplasmic encephalitis is the most common cause of central nervous system infection [3, 4]. In patients with acquired immune deficiency syndrome (AIDS) who have a CD4 count <100 cells/μL, toxoplasmosis reactivated in approximately 30% of the patients who were seropositive and not undergoing antiretroviral therapy (ART) [5, 6]. Therefore, screening for anti-Toxoplasma antibodies and prophylactic administration of cotrimoxazole are required for managing human immunodeficiency virus (HIV) infection [7–9]. It can also manifest as pneumonitis, retinochoroiditis, or disseminated infections [8, 10]. Seropositivity in PLWH should not be disregarded, as these infections appear mainly as a result of the reactivation of latent infections.

The risk factors for Toxoplasma seropositivity, including consumption of raw or undercooked meat, frequent contact with soil, older age, and lower CD4+ lymphocyte counts, have been clarified to some extent [1, 11, 12]. However, some limitations exist in applying these to a special group, such as PLWH, and most studies to date have focused on the risk factors of the seropositive rate. In addition, in recent years, ART and the prevention of opportunistic infections have been increasing in PLWH; however, studies investigating the corresponding changes in actual Toxoplasma infections are insufficient [13].

To this end, this study aimed to investigate the reported toxoplasmosis diagnoses and their risk factors in the Asia-Pacific region using data from the TREAT Asia HIV Observational Database (TAHOD) of the International Epidemiology Databases to Evaluate AIDS (IeDEA) Asia-Pacific.

Materials and methods

Data sources and study population

We analyzed data through July 2022 from TAHOD, a prospective observational cohort study of HIV-positive adults enrolled from 21 clinical sites, which contributes to the IeDEA Asia-Pacific [14]. The TAHOD database and methods have been described previously [15]. Study population was selected from patients enrolled in the TAHOD from 2003 to 2021, according to the latest annual data summary. Due to the observational nature of the cohort, laboratory tests were not performed on a predefined basis but depended on the local practices of the site. PLWH from TAHOD sites with reported cases of toxoplasmosis were included (sites without any reported cases were excluded). We included cases of toxoplasmosis matched to two controls without toxoplasmosis from the same site. Ethics approvals for the study were obtained from the coordinating center (TREAT Asia ethics/amfAR, Bangkok, Thailand), the data management and analysis center (University of New South Wales Human Research Ethics Committee, Sydney, Australia). As the pure observational nature of the study, TAHOD waived the written informed consent. And all TAHOD data transfers are anonymized before submission to the Kirby Institute.

Definition of toxoplasmosis

We defined meaningful toxoplasma infection as definitive and presumptive toxoplasmosis, and definitive toxoplasmosis means patients who confirmed toxoplasmosis by microscopy (histology or cytology). Presumptive toxoplasmosis means patients whom suspicious toxoplasmosis of brain satisfying all three of the following. (i) Recent onset of a focal neurological abnormality consistent with intracranial disease or a reduced level of consciousness; (ii) Evidence by brain imaging (computed tomography or nuclear magnetic resonance) of a lesion having a mass effect or the radiographical appearance of which is enhanced by injection of contrast medium or consistent symptomatic presentation; (iii) Serum antibody to toxoplasmosis or successful response to therapy for toxoplasmosis.

Matching

A prospective toxoplasmosis case was defined as a reported diagnosis of toxoplasmosis (collected as Centers for Disease Control and Prevention [CDC]-category C in our cohort) after TAHOD enrollment. A retrospective case was defined as a reported diagnosis that occurred prior to entry into the TAHOD. To account for differences in site and time period, prospective cases were matched to prospective controls, while retrospective cases were matched to retrospective controls from the same site and time period. Prospective controls were those without evidence of toxoplasmosis with prospective follow-up data available during the same period (+/- 3 months) as the date of toxoplasmosis diagnosis in the prospective case. Retrospective controls were those without evidence of toxoplasmosis who had retrospective (prior to cohort enrollment) data available within the same timeframe as the retrospective control diagnosis. The controls were randomly selected and were required to have at least a CD4 or viral load (VL) available within the matched timeframe as they were considered key covariates in the study. Controls without both viral load (VL) and CD4 available were not selected.

Statistical analysis

Factors associated with toxoplasmosis were analyzed using conditional logistic regression to account for matching. The regression models were fitted using backward stepwise procedures. Factors that were significant in univariate analyses (p<0.10) were included in the multivariate analyses. Factors with p<0.05 in the final multivariate model were considered statistically significant. Data management and statistical analyses were performed using SAS software (version 9.4; SAS Institute Inc., Cary, NC, USA) and Stata software version 16.1 (Stata Corp., College Station, TX, USA).

Results

Demographics and clinical characteristics of the study population

Although our data cannot represent the incidence because of the study design, the years in which the subjects diagnosed with toxoplasma are listed in S1 Fig. A total of 269/9576 (2.8%) PLWH were diagnosed with toxoplasmosis from a subset of 19 TAHOD sites from Cambodia, China, Hong Kong SAR, India, Indonesia, Japan, South Korea, Malaysia, the Philippines, Singapore Taiwan, Thailand, and Vietnam, and were matched to 538 controls. Of the 269 cases, 227 (84%) were reported retrospectively and 42 (16%) were prospective diagnoses after cohort enrollment. Baseline characteristics and demographics are presented in Table 1. At the time of toxoplasmosis diagnosis, the median age was 33 years (interquartile range [IQR] 28–38), 80% participants were male, 75% were not on ART. Excluding 63 out of 269 people without CD4 values, 192 (93.2%) had CD4 ≤200 cells/μL and 162 (78.6%) had CD4 ≤100 cells/μL. A total of 55 patients (20.4%) who received prophylactic cotrimoxazole, defined as cotrimoxazole use within 3 months prior to the diagnosis of toxoplasmosis, were within the same matched time frame for controls.

Table 1. Demographics and clinical characteristics of the study population.

Number of patients (%) Number of controls without toxoplasmosis (%) Number of cases with toxoplasmosis (%)
N = 807 N = 538 N = 269
Age (years) Median = 33, IQR (28–40) Median = 33, IQR (28–40) Median = 33, IQR (28–38)
≤30 300 (37.2) 205 (38.1) 95 (35.3)
31–40 330 (40.9) 213 (39.6) 117 (43.5)
41–50 124 (15.4) 84 (15.6) 40 (14.9)
>50 53 (6.6) 36 (6.7) 17 (6.3)
Sex
Male 573 (71.0) 359 (66.7) 214 (79.6)
Female 234 (29.0) 179 (33.3) 55 (20.4)
Mode of HIV exposure
Heterosexual 546 (67.7) 378 (70.3) 168 (62.5)
MSM 66 (8.2) 47 (8.7) 19 (7.1)
Injecting drug use 153 (19.0) 82 (15.2) 71 (26.4)
Other/Unknown 42 (5.2) 31 (5.8) 11 (4.1)
ART
NRTI+NNRTI 204 (25.3) 153 (28.4) 51 (19.0)
NRTI+PI 27 (3.3) 18 (3.3) 9 (3.3)
Other 24 (3.0) 16 (3.0) 8 (3.0)
None 552 (68.4) 351 (65.2) 201 (74.7)
CD4 (cells/μL) Median = 113, IQR (35–301.5) Median = 268, IQR (132–483) Median = 40.5, IQR (20–83)
≤50 141 (17.5) 16 (3.0) 125 (46.5)
51–100 56 (6.9) 19 (3.5) 37 (13.8)
101–200 74 (9.2) 44 (8.2) 30 (11.2)
>200 137 (17.0) 123 (22.9) 14 (5.2)
Not tested 399 (49.4) 336 (62.5) 63 (23.4)
VL (copies/mL) Median = 6660, IQR (49–170000) Median = 52, IQR (49–15065) Median = 100000, IQR (6864.5–260000)
<1000 76 (9.4) 60 (11.2) 16 (5.9)
≥1000 91 (11.3) 27 (5.0) 64 (23.8)
Not tested 640 (79.3) 451 (83.8) 189 (70.3)
HBV co-infection
Negative 577 (71.5) 390 (72.5) 187 (69.5)
Positive 64 (7.9) 35 (6.5) 29 (10.8)
Not tested 166 (20.6) 113 (21.0) 53 (19.7)
HCV co-infection
Negative 440 (54.5) 300 (55.8) 140 (52.0)
Positive 160 (19.8) 91 (16.9) 69 (25.7)
Not tested 207 (25.7) 147 (27.3) 60 (22.3)
Prior AIDS
No 434 (53.8) 434 (80.7) 0 (0.0)
Yes 373 (46.2) 104 (19.3) 269 (100.0)
Prophylactic cotrimoxazole use
No 664 (82.3) 450 (83.6) 214 (79.6)
Yes 143 (17.7) 88 (16.4) 55 (20.4)
Open in a new tab

Data are presented as the median (interquartile range [IQR]) or number (%) unless otherwise indicated. OR, odds ratio; HIV, human immunodeficiency virus; MSM, men who have sex with men; ART, antiretroviral therapy; NRTI, nucleoside reverse transcriptase inhibitor; NNRTI, non-nucleoside reverse transcriptase inhibitor; PI, protease inhibitor; VL, viral load; HBV, hepatitis B virus; HCV, hepatitis C virus; AIDS; acquired immune deficiency syndrome.

Risk factors for toxoplasmosis

Table 2 shows that factors associated with toxoplasmosis included abstaining from ART (odds ratio [OR] 3.62, 95% confidence interval [CI] 1.81–7.24) in comparison to receiving nucleoside/nucleotide reverse transcriptase (NRTI) plus non-nucleoside reverse transcriptase inhibitors (NNRTIs), acquiring HIV through injection drug use (IDU) (OR 2.27, 95% CI 1.15–4,47) as opposed to engaging in heterosexual intercourse, and testing positive for hepatitis B virus (HBV) surface antigen (OR 3.19, 95% CI 1.41–7.21). Toxoplasmosis was less likely with in patients with higher CD4 counts (51–100 cells/μL: OR 0.41, 95% CI 0.18–0.96; 101–200 cells/μL: OR 0.14, 95% CI 0.06–0.34; >200 cells/μL: OR 0.02, 95% CI 0.01–0.06) compared to in patients with CD4 ≤50 cells/μL. Meanwhile, the use of prophylactic cotrimoxazole was not associated with toxoplasmosis.

Table 2. Risk factors associated with toxoplasmosis.

Number of subjects Univariate analysis Multivariate analysis
Control group Case group OR 95% CI p OR 95% CI p
Total 538 269
Age (years) 0.839
≤30 205 95 1
31–40 213 117 1.18 (0.85, 1.65) 0.320
41–50 84 40 1.03 (0.65, 1.63) 0.899
>50 36 17 1.02 (0.54, 1.92) 0.950
Sex
Male 359 214 1
Female 179 55 0.49 (0.34, 0.71) <0.001
Mode of HIV exposure <0.001 0.045
Heterosexual 378 168 1 1
MSM 47 19 0.87 (0.48, 1.56) 0.636 1.88 (0.79, 4.47) 0.152
Injecting drug use 82 71 2.69 (1.69, 4.28) <0.001 2.27 (1.15, 4.47) 0.018
Other/Unknown 31 11 0.80 (0.39, 1.64) 0.535 0.72 (0.23, 2.29) 0.580
ART 0.007 0.003
NRTI+NNRTI 153 51 1 1
NRTI+PI 18 9 1.76 (0.72, 4.31) 0.213 1.96 (0.49, 7.79) 0.337
Other 16 8 1.97 (0.77, 5.05) 0.156 1.83 (0.45, 7.49) 0.401
None 351 201 2.24 (1.43, 3.53) <0.001 3.62 (1.81, 7.24) <0.001
CD4 (cells/μL) <0.001 <0.001
≤50 16 125 1 1
51–100 19 37 0.35 (0.16, 0.77) 0.010 0.41 (0.18, 0.96) 0.039
101–200 44 30 0.15 (0.07, 0.32) <0.001 0.14 (0.06, 0.34) <0.001
>200 123 14 0.02 (0.01, 0.05) <0.001 0.02 (0.01, 0.06) <0.001
Not tested 336 63
VL (copies/mL)
<1000 60 16 1
≥1000 27 64 9.83 (4.4, 21.96) 0.000
Not tested 451 189
HBV co-infection
Negative 390 187 1 1
Positive 35 29 1.71 (1.02, 2.86) 0.042 3.19 (1.41, 7.21) 0.005
Not tested 113 53
HCV co-infection
Negative 300 140 1
Positive 91 69 1.90 (1.22, 2.94) 0.004
Not tested 147 60
Prior AIDS
No 434 0 N/A
Yes 104 269
Prophylactic cotrimoxazole use
No 450 214 1
Yes 88 55 1.35 (0.91, 1.99) 0.136
Open in a new tab

Data are presented as the median (IQR) or number (%) unless otherwise indicated. OR; odds ratio, HIV; Human immunodeficiency virus, MSM; men who have sex with men, ART; antiretroviral therapy, NRTIs; nucleoside reverse transcriptase inhibitors, NNRTIs; non-nucleoside reverse transcriptase inhibitors, PIs; protease inhibitors, VL; viral load, HBV; hepatitis B virus, HCV; hepatitis C virus, AIDS; acquired immune deficiency syndrome.

Discussion

Toxoplasmosis is one of the most common opportunistic infections, affecting more than one-third of the global population. The extent of infection varies according to region, age distribution, dietary habits, and lifestyle. Although the seroprevalence rate in the general population is low in the Asia-Pacific region, latent infection in PLWH is high in some regions of East Asia [2, 11, 16]. In addition, in PLWH, these latent infections are mainly manifests as Toxoplasma encephalopathy, which can lead to mortality and severe sequelae. Low CD4+ lymphocytes are a known risk factor, and active surveillance and evaluation are required in PLWH.

In the present study, we assessed clinically significant toxoplasmosis, including confirmed toxoplasmosis or cerebral toxoplasmosis, which are the most common manifestations of Toxoplasma infection in PLWH. Toxoplasma seroprevalence differs with differing local environment; therefore, we analyzed the risk factors using site-based matched case-control studies. Consistent with the results of several previous studies, our study showed that the risk of toxoplasmosis increased in patients who did not receive ART compared to those who received NRTI plus NNRTI. Furthermore, CD4 value was lower in the toxoplasmosis group compared to the control. Excluding cases without CD4 test results, the majority had advanced HIV, with 93.2% having CD4 ≤200 cells/μL. Assuming the same seroprevalence as site matching was performed, low CD4 count is a prominent risk factor for overt toxoplasma infection. Therefore, immune reconstitution through early diagnosis and use of ART remains an important task. Also, compared to the heterosexual mode of HIV exposure and HBV co-infection, IDU increased the risk of toxoplasmosis. The precise etiology behind the association of HBV co-infection with toxoplasmosis in our study remains unclear; however, this association may be attributed to socioeconomic status. Socioeconomic status is also associated with the prevalence of HIV and toxoplasmosis, and several studies have strongly suggested the impact of social and economic factors on the prevalence of HBV [17–20]. Although our study showed that HBV co-infection increases the risk of Toxoplasma infection, additional research is needed to clarify the exact causal relationship. In the general population, the prevalence of Toxoplasma is high in cases of substance abuse or IDU, suggesting that PLWH may also be affected [21, 22]. In addition, HIV-related cerebral toxoplasmosis occurs frequently in PLWH in low-to middle-income countries, which could be attributed to the fact that IDU and HBV co-infection are common in regions with poor economic conditions [3]. Our study did not find an association between age and increased risk of toxoplasmosis, unlike other study [23]. Perhaps because the previous study was a comparative study based on seroprevalence, and because seroconversion occurs due to exposure to various environments as one ages, so it may be difficult to correlate it as an actual meaningful infection. Also, prophylactic cotrimoxazole administration did not contribute to lowering the risk of toxoplasmosis. When we first analyzed cotrimoxazole administration before and after the diagnosis of toxoplasmosis, cotrimoxazole administration was significantly high in the case group. But when limited to prophylactic use, there was no difference from the control group. This suggests that there might be a problem with medication compliance, but our study cannot prove it.

This study has several other limitations. Both retrospective and prospective studies were included to maximize the number of cases. However, we could not determine the true prevalence of toxoplasmosis in our cohort. As most of our cases were diagnosed before cohort entry, with historical data reporting being voluntary, owing to the prospective nature of the cohort, we found it impossible to capture all toxoplasmosis diagnoses that occurred in TAHOD. Therefore, we were unable to determine the annual proportion of toxoplasmosis diagnoses over time. Because toxoplasmosis cases were identified through CDC-C category reporting, we were unable to assess further details of the diagnostic pathology.

Conclusions

Our findings indicate that symptomatic toxoplasmosis is rare but still occurs in PLWH in the Asia-Pacific region, especially in the context of delayed diagnosis, causing advanced HIV disease. Immune reconstitution through early diagnosis and ART administration remains a priority in Asian PLWH.

Supporting information

S1 Fig. Year of toxoplasmosis diagnosis.

(DOCX)

pone.0306245.s001.docx (78.6KB, docx)

Acknowledgments

The TREAT Asia HIV Observational Database is an initiative of TREAT Asia, a program of amfAR, The Foundation for AIDS Research, with support from the U.S. National Institutes of Health’s National Institute of Allergy and Infectious Diseases, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Cancer Institute, the National Institute of Mental Health, National Institute on Drug Abuse, the National Heart, Lung, and Blood Institute, National Institute on Alcohol Abuse and Alcoholism, National Institute of Diabetes and Digestive and Kidney Diseases, and Fogarty International Center, as part of the International Epidemiology Databases to Evaluate AIDS (IeDEA; U01AI069907). The Kirby Institute is funded by the Australian Government Department of Health and Aging and is affiliated with the Faculty of Medicine, UNSW, Sydney. The content of this publication is the sole responsibility of the authors and does not necessarily represent the official views of any of the governments or institutions mentioned above.

TAHOD study members

V Khol*, V Ouk, C Pov: National Center for HIV/AIDS, Dermatology & STDs, Phnom Penh, Cambodia; FJ Zhang*, HX Zhao, N Han: Beijing Ditan Hospital, Capital Medical University, Beijing, China; MP Lee*, PCK Li, TS Kwong, TH Li: Queen Elizabeth Hospital, Hong Kong SAR; N Kumarasamy*, C Ezhilarasi: Chennai Antiviral Research and Treatment Clinical Research Site (CART CRS), VHS-Infectious Diseases Medical Centre, VHS, Chennai, India; S Pujari*, K Joshi, S Gaikwad, A Chitalikar: Institute of Infectious Diseases, Pune, India; RT Borse*, V Mave, I Marbaniang, S Nimkar: BJ Government Medical College and Sassoon General Hospital, Pune, India; IKA Somia*, TP Merati, AAS Sawitri, F Yuliana: Faculty of Medicine Udayana University—Prof. Dr. I.G.N.G. Ngoerah Hospital, Bali, Indonesia; E Yunihastuti*, A Widhani, S Maria, TH Karjadi: Faculty of Medicine Universitas Indonesia—Dr. Cipto Mangunkusumo General Hospital, Jakarta, Indonesia; J Tanuma*, S Oka, H Uemura, Y Koizumi: National Center for Global Health and Medicine, Tokyo, Japan; JY Choi*, Na S, JM Kim: Division of Infectious Diseases, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea; YM Gani*, NB Rudi: Hospital Sungai Buloh, Sungai Buloh, Malaysia; I Azwa*, A Kamarulzaman, SF Syed Omar, S Ponnampalavanar: University Malaya Medical Centre, Kuala Lumpur, Malaysia; R Ditangco*, MK Pasayan, ML Mationg: Research Institute for Tropical Medicine, Muntinlupa City, Philippines; HP Chen*, YJ Chan, PF Wu: Taipei Veterans General Hospital, Taipei, Taiwan; OT Ng*, PL Lim, LS Lee, T Yap: Tan Tock Seng Hospital, National Centre for Infectious Diseases, Singapore (note: OT Ng is also supported by the Singapore Ministry of Health’s (MOH) National Medical Research Council (NMRC) Clinician Scientist Award (MOH-000276). Any opinions, findings, conclusions, or recommendations expressed in this material are those of the author(s) and do not reflect the views of MOH/NMRC); A Avihingsanon*, S Gatechompol, P Phanuphak, C Phadungphon: HIV-NAT/Thai Red Cross AIDS Research Centre, Bangkok, Thailand; S Kiertiburanakul*, A Phuphuakrat, L Chumla, N Sanmeema: Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand; R Chaiwarith*, T Sirisanthana, J Praparattanapan, K Nuket: Faculty of Medicine and Research Institute for Health Sciences, Chiang Mai University, Chiang Mai, Thailand; S Khusuwan*, P Kambua, S Pongprapass, J Limlertchareonwanit: Chiangrai Prachanukroh Hospital, Chiang Rai, Thailand; TN Pham*, KV Nguyen, DTH Nguyen, DT Nguyen: National Hospital for Tropical Diseases, Hanoi, Vietnam; CD Do*, AV Ngo, LT Nguyen: Bach Mai Hospital, Hanoi, Vietnam; AH Sohn*, JL Ross*, B Petersen: TREAT Asia, amfAR—The Foundation for AIDS Research, Bangkok, Thailand; MG Law*, A Jiamsakul*, D Rupasinghe: The Kirby Institute, UNSW Sydney, NSW, Australia.

* TAHOD Steering Committee Members

Abbreviations

AIDS

acquired immune deficiency syndrome

ART

antiretroviral therapy

CDC

Centers for Disease Control and Prevention

HBV

hepatitis B virus

HCV

hepatitis C virus

HIV

Human Immunodeficiency Virus

IDU

injection drug use

IQR

Interquartile range

MSM

men who have sex with men

NNRTI

non-nucleoside reverse transcriptase inhibitors

NRTI

nucleoside reverse transcriptase inhibitors

OR

odds ratio

PI

protease inhibitor

PLWH

people living with HIV

TAHOD

TREAT Asia HIV Observational Database

VL

viral load

Data Availability

The following restrictions on sharing a study data should be noted: Study data is available on request but is not publicly available without restriction, as it might contain potentially identifying information (e.g. date of birth), and because study data is considered owned by the study sites contributing data. These data sharing restrictions are imposed by the TAHOD study group, including participating site principle investigators. Data requests may be sent to the study data manager, Awachana Jiamsakul (Ajiamsakul@kirby.unsw.edu.au), at the Kirby Institute, UNSW, Sydney, Australia, which serves as the study’s regional data center. We appreciate your updating of our Data Availability statement to reflect this information.

Funding Statement

The authors received no specific funding for this work.

References

  • 1.Saadatnia G. and Golkar M., A review on human toxoplasmosis. Scand J Infect Dis, 2012. 44(11): p. 805–14. doi: 10.3109/00365548.2012.693197 [DOI] [PubMed] [Google Scholar]
  • 2.Pappas G., Roussos N., and Falagas M.E., Toxoplasmosis snapshots: global status of Toxoplasma gondii seroprevalence and implications for pregnancy and congenital toxoplasmosis. Int J Parasitol, 2009. 39(12): p. 1385–94. doi: 10.1016/j.ijpara.2009.04.003 [DOI] [PubMed] [Google Scholar]
  • 3.Vidal J.E., HIV-related cerebral toxoplasmosis revisited: current concepts and controversies of an old disease. Journal of the International Association of Providers of AIDS Care (JIAPAC), 2019. 18: p. 2325958219867315. doi: 10.1177/2325958219867315 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 4.Dian S., Ganiem A.R., and Ekawardhani S., Cerebral toxoplasmosis in HIV-infected patients: a review. Pathogens and Global Health, 2023. 117(1): p. 14–23. doi: 10.1080/20477724.2022.2083977 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5.Montoya J.G. and Liesenfeld O., Toxoplasmosis. Lancet, 2004. 363(9425): p. 1965–76. doi: 10.1016/S0140-6736(04)16412-X [DOI] [PubMed] [Google Scholar]
  • 6.Schlüter D. and Barragan A., Advances and challenges in understanding cerebral toxoplasmosis. Frontiers in immunology, 2019. 10: p. 424386. doi: 10.3389/fimmu.2019.00242 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 7.Benson C.A., et al., Guidelines for prevention and treatment opportunistic infections in HIV-infected adults and adolescents: recommendations from CDC, the National Institutes of Health, and the HIV Medicine Association/Infectious Diseases Society of America. MMWR. Recommendations and reports: Morbidity and mortality weekly report. Recommendations and reports / Centers for Disease Control. 2009; 58(RR-4):1–207; quiz CE1-4., 2009. [PubMed] [Google Scholar]
  • 8.Basavaraju A., Toxoplasmosis in HIV infection: An overview. Trop Parasitol, 2016. 6(2): p. 129–135. doi: 10.4103/2229-5070.190817 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 9.Aerts, R., et al., Guidelines for the management of Toxoplasma gondii infection and disease in patients with haematological malignancies and after haematopoietic stem-cell transplantation: guidelines from the 9th European Conference on Infections in Leukaemia, 2022. The Lancet Infectious Diseases, 2023. [DOI] [PubMed]
  • 10.Porter S.B. and Sande M.A., Toxoplasmosis of the central nervous system in the acquired immunodeficiency syndrome. New England Journal of Medicine, 1992. 327(23): p. 1643–1648. doi: 10.1056/NEJM199212033272306 [DOI] [PubMed] [Google Scholar]
  • 11.Rostami, A., et al., Global and Regional Prevalence and Burden of Latent and Acute Toxoplasmosis in People Living With HIV: an Updated Systematic Review and Meta-analysis. 2020.
  • 12.Safarpour H., et al., Global status of Toxoplasma gondii infection and associated risk factors in people living with HIV. Aids, 2020. 34(3): p. 469–474. doi: 10.1097/QAD.0000000000002424 [DOI] [PubMed] [Google Scholar]
  • 13.Reported number of people receiving antiretroviral therapy. 2022 2022-09-19; https://www.who.int/data/gho/data/indicators/indicator-details/GHO/reported-number-of-people-receiving-antiretroviral-therapy.
  • 14.Duda S.N., et al., Characteristics and comprehensiveness of adult HIV care and treatment programmes in Asia-Pacific, sub-Saharan Africa and the Americas: results of a site assessment conducted by the International epidemiologic Databases to Evaluate AIDS (IeDEA) Collaboration. J Int AIDS Soc, 2014. 17: p. 19045. doi: 10.7448/IAS.17.1.19045 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 15.Zhou J., et al., The TREAT Asia HIV Observational Database: baseline and retrospective data. J Acquir Immune Defic Syndr, 2005. 38(2): p. 174–9. doi: 10.1097/01.qai.0000145351.96815.d5 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 16.Shin D.W., et al., Seroprevalence of Toxoplasma gondii infection and characteristics of seropositive patients in general hospitals in Daejeon, Korea. Korean J Parasitol, 2009. 47(2): p. 125–30. doi: 10.3347/kjp.2009.47.2.125 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 17.Wang X., et al., Economic-related inequalities in hepatitis B virus infection among 115.8 million pregnant women in China from 2013 to 2020. EClinicalMedicine, 2022. 49: p. 101465. doi: 10.1016/j.eclinm.2022.101465 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 18.Tosun S., et al., The impact of economic and social factors on the prevalence of hepatitis B in Turkey. BMC public health, 2018. 18: p. 1–9. doi: 10.1186/s12889-018-5575-6 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 19.Wilking H., et al., Prevalence, incidence estimations and risk factors of Toxoplasma gondii infection in Germany: a representative, cross-sectional, serological study. Scientific reports, 2016. 6(1): p. 22551. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 20.Mareze M., et al., Socioeconomic vulnerability associated to Toxoplasma gondii exposure in southern Brazil. PLoS One, 2019. 14(2): p. e0212375. doi: 10.1371/journal.pone.0212375 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 21.Sharifzadeh M., et al., Sero-molecular survey on Toxoplasma gondii infection among drug addicted and non-addicted individuals: a case—control study. BMC Infectious Diseases, 2022. 22(1): p. 19. doi: 10.1186/s12879-021-06979-8 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 22.Elmorsy E., et al., An association between latent toxoplasmosis and substance abuse: an Egyptian Center Study. Journal of Addictive Diseases, 2018. 37(3–4): p. 165–172. doi: 10.1080/10550887.2019.1641378 [DOI] [PubMed] [Google Scholar]
  • 23.Falusi O., et al., Prevalence and predictors of Toxoplasma seropositivity in women with and at risk for human immunodeficiency virus infection. Clin Infect Dis, 2002. 35(11): p. 1414–7. doi: 10.1086/344462 [DOI] [PMC free article] [PubMed] [Google Scholar]

Decision Letter 0

Masoud Foroutan

17 Nov 2023

PONE-D-23-29849Risk factors for toxoplasmosis in people living with HIV in the Asia-Pacific regionPLOS ONE

Dear Dr. Choi,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

==============================

ACADEMIC EDITOR:

Please submit your revised manuscript by Jan 01 2024 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.

Please include the following items when submitting your revised manuscript:

  • A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

  • A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

  • An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Masoud Foroutan, Ph.D; Assistant Professor

Academic Editor

PLOS ONE

Journal requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2. Note from Emily Chenette, Editor in Chief of PLOS ONE, and Iain Hrynaszkiewicz, Director of Open Research Solutions at PLOS: Did you know that depositing data in a repository is associated with up to a 25% citation advantage (https://doi.org/10.1371/journal.pone.0230416)? If you’ve not already done so, consider depositing your raw data in a repository to ensure your work is read, appreciated and cited by the largest possible audience. You’ll also earn an Accessible Data icon on your published paper if you deposit your data in any participating repository (https://plos.org/open-science/open-data/#accessible-data).

3. Thank you for stating the following in the Acknowledgments Section of your manuscript:

“The TREAT Asia HIV Observational Database is an initiative of TREAT Asia, a program of amfAR, The Foundation for AIDS Research, with support from the U.S. National Institutes of Health’s National Institute of Allergy and Infectious Diseases, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Cancer Institute, the National Institute of Mental Health, National Institute on Drug Abuse, the National Heart, Lung, and Blood Institute, National Institute on Alcohol Abuse and Alcoholism, National Institute of Diabetes and Digestive and Kidney Diseases, and Fogarty International Center, as part of the International Epidemiology Databases to Evaluate AIDS (IeDEA; U01AI069907). The Kirby Institute is funded by the Australian Government Department of Health and Aging and is affiliated with the Faculty of Medicine, UNSW, Sydney. The content of this publication is the sole responsibility of the authors and does not necessarily represent the official views of any of the governments or institutions mentioned above.”

We note that you have provided funding information that is currently declared in your Funding Statement. However, funding information should not appear in the Acknowledgments section or other areas of your manuscript. We will only publish funding information present in the Funding Statement section of the online submission form.

Please remove any funding-related text from the manuscript and let us know how you would like to update your Funding Statement. Currently, your Funding Statement reads as follows:

“The authors received no specific funding for this work.”

Please include your amended statements within your cover letter; we will change the online submission form on your behalf.

4. In your Data Availability statement, you have not specified where the minimal data set underlying the results described in your manuscript can be found. PLOS defines a study's minimal data set as the underlying data used to reach the conclusions drawn in the manuscript and any additional data required to replicate the reported study findings in their entirety. All PLOS journals require that the minimal data set be made fully available. For more information about our data policy, please see http://journals.plos.org/plosone/s/data-availability.

"Upon re-submitting your revised manuscript, please upload your study’s minimal underlying data set as either Supporting Information files or to a stable, public repository and include the relevant URLs, DOIs, or accession numbers within your revised cover letter. For a list of acceptable repositories, please see http://journals.plos.org/plosone/s/data-availability#loc-recommended-repositories. Any potentially identifying patient information must be fully anonymized.

Important: If there are ethical or legal restrictions to sharing your data publicly, please explain these restrictions in detail. Please see our guidelines for more information on what we consider unacceptable restrictions to publicly sharing data: http://journals.plos.org/plosone/s/data-availability#loc-unacceptable-data-access-restrictions. Note that it is not acceptable for the authors to be the sole named individuals responsible for ensuring data access.

We will update your Data Availability statement to reflect the information you provide in your cover letter.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

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

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: No

Reviewer #2: Partly

**********

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

Reviewer #1: No

Reviewer #2: No

**********

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

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

**********

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

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: 1. Because patient geographical distribution and infection period difference are also critical for toxoplasmosis infection, the manuscript needs to analyze these data.

2. Because many patients have not taken ART and lack CD4 & viral load data, these data deficiencies could interfere with the risk factors assessment.

3. The IVDU etiology and HBV infection should be considered as counfounding factors and these factors are highly associated to socioeconomic status which could be the risk factor of toxoplasmosis infection.

4. The disease type of toxoplasmosis should be described in this manuscript.

Reviewer #2: In this paper, Hyun Lee et all present a retrospective/prospective case control study to assess risk factors for toxoplasmosis in PLWH in the ASIA Pacific region. With the current use of ART worldwide, opportunistic infections associated to AIDS are infrequent and deserve less attention. Thus, the effort of the authors in conducting this study should be recognized.

However, the study has some important limitations.

-Despite in the Methods section they comment that “controls without VL or CD4 unavailable within the matched timeframe were not selected because they were considered key covariates”, 62.5% and 83.8% of controls were not tested for CD4 or VL respectively (compared with 23.4% and 70.3% in cases). Could the authors clarify this relevant aspect of their study?

-In the abstract they say that 71% of toxo pts had CD4 < 200 , that means that 29% had >200, what is surprising as almost all PLWH with toxo have CD4 < 200 and mostly <100. But in fact, as 23.4% of these cases were not tested for CD4, only 14/206 (7.6%) with tested CD4 had CD4 >200, thus about 92% of tested pts, had CD4 <200. Thus, the sentence in the abstract should be modified, and it should be also mentioned in the Results and Discussion sections..

-It is well known that cotrimoxazole protects against toxo in immunosuppressed PLWH. The fact that in this study it seems that no differences in cotrimoxazole use was found between cases and controls, suggests that adherence to prophylaxis might be an issue in this population. Authors should comment this aspect in the Discussion section.

-In the multivariate analysis, variables have been adjusted for CD4 count? It may be that PLWH being IDU or HBV+ had lower CD4 count (as probably occurred with pts not receiving ART) and if adjusting results may vary.

-I would say immune reconstitution instead of immune reconstruction

**********

6. 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: Yes: Tun-Chieh Chen

Reviewer #2: No

**********

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PLoS One. 2024 Jul 1;19(7):e0306245. doi: 10.1371/journal.pone.0306245.r002

Author response to Decision Letter 0

18 Dec 2023

Response to Reviewers’ comments

Reviewer #1

1. Because patient geographical distribution and infection period difference are also critical for toxoplasmosis infection, the manuscript needs to analyze these data.

Author’s response #1

We agree with the reviewer that geographical distribution and infection period differences are important in toxoplasmosis infection. Like the reviewer, we are aware of the importance of these two factors, and therefore have designed our study to analyse the site and time effect by matching by site and time period of toxoplasmosis infection so that cases and controls were compared within the same site and in a similar time frame. Matching by site and time period removed the known confounding effects of the two risk factors and allowed for comparison of cases and controls without the influence of these factors. Although matching does not output the effect sizes in the regression table for site and time period of infection (unlike the regular unmatched analyses), the regression model had “analysed” or taken into account these two factors by way of matching through the use of conditional logistic regression “conditioned on matched pairs”. Therefore, site and time were analysed by conditional logistic regression through matching. Unfortunately, we are not able to provide the number of cases by individual site to maintain confidentiality for the network, however we have listed the countries that were included, and have also further clarified the matching in our methods.

“To account for differences in site and time period, prospective cases were matched to prospective controls, while retrospective cases were matched to retrospective controls from the same site and time period.”

“Factors associated with toxoplasmosis were analyzed using conditional logistic regression to account for matching.”

“A total of 269/9576 (2.8%) PLWH were diagnosed with toxoplasmosis from a subset of 19 TAHOD sites from Cambodia, China, Hong Kong SAR, India, Indonesia, Japan, South Korea, Malaysia, the Philippines, Singapore Taiwan, Thailand, and Vietnam, and were matched to 538 controls.”

2. Because many patients have not taken ART and lack CD4 & viral load data, these data deficiencies could interfere with the risk factors assessment.

Author’s response #2

Thank you for your comment. As you said, it is disappointing that many of the subjects did not have CD4 or VL values. But while revising the paper this time, we excluded people without CD4 values, and found the vast majority (93.2%, instead of the previous 71%) were advanced HIV with a CD4 count of less than 200. Like your good opinion, most of the people who actually participated in the study lacked of data, but I think these results will be valuable.

3. The IVDU etiology and HBV infection should be considered as counfounding factors and these factors are highly associated to socioeconomic status which could be the risk factor of toxoplasmosis infection.

Author’s response #3

We would like to thank the reviewer for this suggestion. Injecting drug users (IDU) are normally known to be associated with hepatitis C co-infection, rather than hepatitis B. From our analysis, hepatitis C was not significant in the multivariate analysis. We have also tested for collinearity between mode of HIV exposure and HBV and found that there was no collinearity between the two variables (mean VIF=1.00).

4. The disease type of toxoplasmosis should be described in this manuscript.

Author’s response #4

We have updated the Materials and Methods section as follows; (page 5, line 133)

Definition of toxoplasmosis

We defined meaningful toxoplasma infection as definitive and presumptive toxoplasmosis, and definitive toxoplasmosis means patients who confirmed toxoplasmosis by microscopy (histology or cytology). Presumptive toxoplasmosis means patients whom suspicious toxoplasmosis of brain satisfying all three of the following. (i) Recent onset of a focal neurological abnormality consistent with intracranial disease or a reduced level of consciousness; (ii) Evidence by brain imaging (computed tomography or nuclear magnetic resonance) of a lesion having a mass effect or the radiographical appearance of which is enhanced by injection of contrast medium or consistent symptomatic presentation; (iii) Serum antibody to toxoplasmosis or successful response to therapy for toxoplasmosis.

 

Reviewer #2

1. Despite in the Methods section they comment that “controls without VL or CD4 unavailable within the matched timeframe were not selected because they were considered key covariates”, 62.5% and 83.8% of controls were not tested for CD4 or VL respectively (compared with 23.4% and 70.3% in cases). Could the authors clarify this relevant aspect of their study?

Author’s response #1

We apologize if this was unclear. We excluded controls without both CD4 AND VL, but allowed controls to be included if they had either a CD4 or a VL available, in order to maximize our sample size. We have clarified this in our methods:

“The controls were randomly selected and were required to have at least a CD4 or VL available within the matched timeframe as they were considered key covariates in the study. Controls without both viral load and CD4 available were not selected.”

2. In the abstract they say that 71% of toxo pts had CD4 < 200 , that means that 29% had >200, what is surprising as almost all PLWH with toxo have CD4 < 200 and mostly <100. But in fact, as 23.4% of these cases were not tested for CD4, only 14/206 (7.6%) with tested CD4 had CD4 >200, thus about 92% of tested pts, had CD4 <200. Thus, the sentence in the abstract should be modified, and it should be also mentioned in the Results and Discussion sections.

Author’s response #2

We would like to thank the reviewer for this suggestion. As you mentioned, I agreed to calculate the proportion of people whose CD4 values were measured, so we revised the abstract and result sections of the main text as follows, and additionally mentioned this in the discussion, as follows; (page 12, line 223)

“Excluding 63 out of 269 people without CD4 values, 192 (93.2%) had CD4 ≤200 cells/µL and 162 (78.6%) had CD4 ≤100 cells/µL.”

“Furthermore, CD4 value was lower in the toxoplasmosis group compared to the control. Excluding cases without CD4 test results, the majority had advanced HIV, with 93.2% having CD4 ≤200 cells/µL. Assuming the same seroprevalence as site matching was performed, low CD4 count is a prominent risk factor for overt toxoplasma infection. Therefore, immune reconstitution through early diagnosis and use of ART remains an important task.”

3. It is well known that cotrimoxazole protects against toxo in immunosuppressed PLWH. The fact that in this study it seems that no differences in cotrimoxazole use was found between cases and controls, suggests that adherence to prophylaxis might be an issue in this population. Authors should comment this aspect in the Discussion section.

Author’s response #3

Thank you for your comments. In fact, although the CD4 count was lower in the case group compared to the control, it was not significantly higher in those who took cotrimoxazole for prophylactic purposes. In fact, the overall cotrimoxazole administration before and after diagnosis was high in the case group. But there was no difference when analyzed with preventive purposes and it means that there may have been a problem with adherence, and this is an important result, so details about this have been added in the discussion section as follows; (page 12, line 243)

“Also, prophylactic cotrimoxazole administration did not contribute to lowering the risk of toxoplasmosis. When we first analyzed cotrimoxazole administration before and after the diagnosis of toxoplasmosis, cotrimoxazole administration was significantly high in the case group. But when limited to prophylactic use, there was no difference from the control group. This suggests that there might be a problem with medication compliance, but our study cannot prove it.”

4. In the multivariate analysis, variables have been adjusted for CD4 count? It may be that PLWH being IDU or HBV+ had lower CD4 count (as probably occurred with pts not receiving ART) and if adjusting results may vary.

Author’s response #4

The multivariate results were adjusted for CD4.

5. I would say immune reconstitution instead of immune reconstruction

Author’s response #5

As suggested, we have modified the pointed words in Conclusion section.

Attachment

Submitted filename: Response to Reviewers.docx

pone.0306245.s002.docx (23.9KB, docx)

Decision Letter 1

Masoud Foroutan

2 May 2024

PONE-D-23-29849R1Risk factors for toxoplasmosis in people living with HIV in the Asia-Pacific regionPLOS ONE

Dear Dr. Choi,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Jun 16 2024 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.

Please include the following items when submitting your revised manuscript:

  • A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

  • A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

  • An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Masoud Foroutan, Ph.D.; Assistant Professor

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

[Note: HTML markup is below. Please do not edit.]

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 #3: (No Response)

**********

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

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #3: (No Response)

**********

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

Reviewer #1: Yes

Reviewer #3: Yes

**********

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

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #3: Yes

**********

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

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #3: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: 1. Thanks for your responses to the questions, and then it makes the information from the manuscript more clear. However, the case distribution and diagnosis time period are also interesting for the readers. Although these factors were matched for the analysis. I recommend that you can provide information about the case's geographical and time period distribution in a small table or in the supplement material. It is much better for the reference of our readers.

Reviewer #3: Dear Author, please:

Use keywords based on MESH.

Mention the prevalence and risk factors in the title.

Many sources are old. Please use new sources from the last 5 years

**********

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: Yes: Tun-Chieh Chen

Reviewer #3: No

**********

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

PLoS One. 2024 Jul 1;19(7):e0306245. doi: 10.1371/journal.pone.0306245.r004

Author response to Decision Letter 1

10 Jun 2024

Reviewer #1

1. Thanks for your responses to the questions, and then it makes the information from the manuscript more clear. However, the case distribution and diagnosis time period are also interesting for the readers. Although these factors were matched for the analysis. I recommend that you can provide information about the case's geographical and time period distribution in a small table or in the supplement material. It is much better for the reference of our readers.

Author’s response #1

We added the information about [Year of toxoplasmosis diagnosis] as supplementary 1 to the first paragraph of the “Demographics and clinical characteristics of the study population” of Result section.

Reviewer #3

1. Dear Author, please: Use keywords based on MESH. Mention the prevalence and risk factors in the title. Many sources are old. Please use new sources from the last 5 years

Author’s response #1

We modified the keywords to be MESH-based, and since prevalence cannot be inferred from our study, only risk factors are mentioned in the title. Lastly, we made some revisions referenced in this study.

Attachment

Submitted filename: Response to Reviewers.docx

pone.0306245.s003.docx (19.7KB, docx)

Decision Letter 2

Masoud Foroutan

14 Jun 2024

Risk factors for toxoplasmosis in people living with HIV in the Asia-Pacific region

PONE-D-23-29849R2

Dear Dr. Choi,

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 will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, 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,

Masoud Foroutan, Ph.D; Assistant Professor

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

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 #3: All comments have been addressed

**********

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

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #3: Yes

**********

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

Reviewer #3: Yes

**********

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

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #3: Yes

**********

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

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #3: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #3: (No Response)

**********

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 #3: No

**********

Acceptance letter

Masoud Foroutan

21 Jun 2024

PONE-D-23-29849R2

PLOS ONE

Dear Dr. Choi,

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

At this stage, our production department will prepare your paper for publication. This includes ensuring the following:

* All references, tables, and figures are properly cited

* All relevant supporting information is included in the manuscript submission,

* There are no issues that prevent the paper from being properly typeset

If revisions are needed, the production department will contact you directly to resolve them. If no revisions are needed, you will receive an email when the publication date has been set. At this time, we do not offer pre-publication proofs to authors during production of the accepted work. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few weeks to review your paper and let you know the next and final steps.

Lastly, 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 customercare@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

Dr. Masoud Foroutan

Academic Editor

PLOS ONE

Associated Data

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

    Supplementary Materials

    S1 Fig. Year of toxoplasmosis diagnosis.

    (DOCX)

    pone.0306245.s001.docx (78.6KB, docx)
    Attachment

    Submitted filename: Response to Reviewers.docx

    pone.0306245.s002.docx (23.9KB, docx)
    Attachment

    Submitted filename: Response to Reviewers.docx

    pone.0306245.s003.docx (19.7KB, docx)

    Data Availability Statement

    The following restrictions on sharing a study data should be noted: Study data is available on request but is not publicly available without restriction, as it might contain potentially identifying information (e.g. date of birth), and because study data is considered owned by the study sites contributing data. These data sharing restrictions are imposed by the TAHOD study group, including participating site principle investigators. Data requests may be sent to the study data manager, Awachana Jiamsakul (Ajiamsakul@kirby.unsw.edu.au), at the Kirby Institute, UNSW, Sydney, Australia, which serves as the study’s regional data center. We appreciate your updating of our Data Availability statement to reflect this information.

    Articles from PLOS ONE are provided here courtesy of PLOS

    RESOURCES