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. 2025 Dec 8;8:3. doi: 10.1186/s42522-025-00186-0

Viral zoonotic disease outbreaks and response strategies in Sub-Saharan Africa: a scoping review

Sherihane Aryeetey 1,2,3, Philip El-Duah 2,4, Jonathan Mawutor Gmanyami 2,5,6, George Agyei 1,2,3, Augustina Angelina Sylverken 3,7, Rexford Mawunyo Dumevi 4, William Tasiame 8, Yaw Adu-Sarkodie 1, Richard Odame Phillips 3,9, Christian Drosten 4,10, Michael Owusu 2,3,11,
PMCID: PMC12801751  PMID: 41354839

Abstract

Background

Viral zoonoses, particularly RNA viruses, pose a growing public health threat in Sub-Saharan Africa (SSA) due to ecological disruption, rapid urbanization, and weak health systems. This scoping review synthesizes the available evidence on viral zoonotic outbreaks in SSA, focusing on documented public health and medical response strategies and the extent to which the One Health approach has been applied.

Methods

We conducted searches of peer-reviewed and grey literature published between January 2005 and March 2025 in PubMed, Scopus, Google Scholar, Google, and website searches including WHO-AFRO and Africa CDC. The search strategy combined Medical Subject Headings (MeSH) and keywords related to “zoonotic viruses,” “outbreaks,” “response,” and “Sub-Saharan Africa.” Eligible studies included outbreak reports, surveillance summaries, case reports, and epidemiological investigations involving human and/or animal viral zoonotic disease outbreaks in SSA. Data on outbreak characteristics, transmission patterns, response strategies, and One Health implementation were extracted.

Results

From an initial pool of 4,534 studies, fifty-two met the inclusion criteria. Rift Valley Fever virus (RVFV), Ebola virus, Marburg virus, Monkeypox, and Lassa virus were the most frequently reported viruses. A notable case of Lassa fever and SARS-CoV-2 co-infection was reported in Guinea. Transmission routes varied: direct contact, vector-borne, sexual, and nosocomial transmission. Reported public health responses included case isolation, contact tracing, community sensitization, vector control, and livestock surveillance, though there was limited formal assessment of their effectiveness. Integration of the One Health approach was inconsistently applied and explicitly documented in only a few studies.

Conclusion

Zoonotic viral outbreaks in Sub-Saharan Africa remain a recurrent and evolving public health challenge due to persistent gaps in surveillance, preparedness, and cross-sector coordination. Strengthening community-based detection, rapid laboratory confirmation, health system capacity for diagnostics and response, and fully operationalizing One Health frameworks is essential to enhance early warning and outbreak control.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42522-025-00186-0.

Keywords: Viral zoonotic disease, Outbreak, Response strategy, Sub-Saharan Africa

Introduction

Viral zoonoses are infections caused by viruses transmitted from animals to humans. These infections pose a significant threat to public health globally and regionally, especially in sub-Saharan Africa (SSA), where ecological, socio-economic, and health system challenges are increasing [1, 2]. The emergence and re-emergence of viral zoonoses, such as Ebola virus disease (EVD), Lassa fever, Rift Valley fever (RVF), and the more recent Coronavirus disease 2019 (COVID-19), have underscored the critical need to understand the transmission patterns, prevalence, and risk factors driving these outbreaks [3, 4].

EVD has been responsible for repeated epidemics in Central and West Africa, with case fatality rates ranging from 25 to 90% and substantial socio-economic disruption [5]. RVF is endemic in East and Southern Africa, with outbreaks often linked to heavy rainfall and flooding that favour mosquito vector proliferation; the disease causes high livestock mortality and substantial economic losses [6]. Mpox, historically endemic in Central Africa, has re-emerged with broader geographic spread, human-to-human transmission, and a growing public health impact [7]. Together, these pathogens exemplify the diverse transmission routes, direct animal contact, vector-borne spread, and human-to-human transmission, that complicate surveillance and control efforts in the region.

Most viral zoonotic pathogens, particularly RNA viruses, are characterized by high mutation rates and adaptability, which increase their potential for spillover from animal to human populations [8]. Rapid urbanization, deforestation, climate change, agricultural expansion, and unregulated human-animal interactions contribute to the frequency and intensity of these outbreaks in SSA [2]. In addition to facilitating the emergence of zoonoses, these dynamics pose significant challenges to surveillance, early detection, and coordinated responses [9]. Viral zoonoses in SSA not only cause morbidity and mortality in humans but also devastate livestock populations, undermining food security and livelihoods [10]. Health systems in SSA are often overburdened during outbreaks, with limited diagnostic capacity, insufficient isolation facilities, and inadequate protective equipment, which amplify nosocomial transmission and strain already fragile infrastructures, as documented during the West Africa Ebola epidemic [11]. Outbreaks also disrupt routine health services, delay care for chronic conditions, and trigger long-term socio-economic consequences in affected communities [12].

The One Health approach recognizes the interconnectedness of human, animal, and environmental health and is critical for addressing these challenges. By promoting cross-sectoral collaboration among public health, veterinary, and environmental sectors, the One Health framework enhances surveillance, risk assessment, and the design of holistic interventions that are essential for preventing and controlling zoonotic spillover [13, 14].

Standard responses to viral zoonotic outbreaks typically involve a combination of early case detection, isolation and clinical management, contact tracing, community engagement, and infection prevention and control (IPC) measures [15]. In more severe outbreaks, additional steps may include movement restrictions, vector control (in vector-borne diseases), mass vaccination (where applicable), targeted culling of infected or exposed animals, and international coordination under the International Health Regulations (IHR). Strengthening preparedness and response capacities within a One Health framework is essential for mitigating the threat of viral zoonoses in SSA [16, 17].

Despite extensive experience with outbreaks, significant gaps in knowledge and practice remain. The true burden of viral zoonoses in SSA is underestimated due to weak surveillance systems and underreporting. Ecological drivers such as climate variability and land-use change are insufficiently integrated into outbreak prediction models, limiting our ability to anticipate epidemics [18]. In addition, limited cross-sectoral coordination also hinders effective One Health implementation, and systematic evaluations of outbreak response strategies are scarce [19]. This review synthesizes available evidence on documented viral zoonotic disease outbreaks in SSA, with focus on the response strategies and One Health approaches reported in literature. Specifically, we examined studies reporting viral zoonotic disease outbreaks in SSA, prevention, and control efforts, and analyse how public health, medical, veterinary, and ecological responses were coordinated. Emphasis is placed on surveillance systems, case management, and, where applicable, vaccination efforts. Rather than formally evaluating intervention effectiveness, the review aims to map existing strategies and their alignment with One Health principles. Ultimately, this review identifies key gaps and proposes actionable improvements for strengthening outbreak preparedness and response across SSA.

Methods

Settings

This scoping review was guided by the methodological framework developed by Arksey and O’Malley (2005) and examined studies reporting on viral zoonotic disease outbreaks and response strategies in sub-Saharan Africa. The review process followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) [20].

Protocol registration

The protocol for this review was registered in Open Science Framework (OSF) and can be found at 10.17605/OSF.IO/UENR5.

Information sources and search strategy

We conducted a comprehensive literature search across electronic bibliographic databases and open-access sources, including PubMed, Scopus, Google Scholar, and Google. We initially identified approximately 228,000 and 843,000 search results from Google and Google Scholar respectively, only the 100 (Google) and 200 (Google Scholar) articles from each database were deemed relevant for screening and subsequent selection based on the study’s inclusion criteria [21]. In addition, the reference lists of included studies and other relevant publications were reviewed to identify eligible articles for further research. The search strategy focused on the core concepts of the review: viral zoonotic diseases, outbreaks, response strategies, and Sub-Saharan Africa. These concepts were operationalized using a range of synonyms tailored to each database, incorporating Medical Subject Headings (MeSH) where applicable. Boolean operators (AND, OR) were employed to optimize search sensitivity and specificity. To capture relevant grey literature, we also searched the websites of key public health organizations, such as the Africa Centres for Disease Control and Prevention (Africa CDC) and the WHO Regional Office for Africa (WHO AFRO). The search was limited to studies published in English between 2005 and 2025, aligning with the implementation of the International Health Regulations (IHR) [22], which marked a global shift toward structured outbreak surveillance, reporting, and coordination frameworks relevant to zoonotic disease management in SSA and ensuring inclusion of up-to-date literature.

Study selection procedures

The inclusion and exclusion criteria were defined based on the Participants, Intervention/Exposure, Comparator, and Outcome (PICO) framework, as detailed below:

Participants/population

The review included outbreak investigation/report, cross-sectional, case-report, and retrospective cohort studies. Both humans and animals were considered in assessing zoonotic disease outbreaks, including their epidemiological characteristics, transmission patterns, and the effectiveness of response strategies.

Intervention(s)/exposure

The exposure of interest was a zoonotic disease outbreak of viral origin.

Comparator(s)/control

Not applicable.

Main outcome

The primary outcome of this review was to identify and describe the epidemiological characteristics and transmission patterns of viral zoonotic disease outbreaks in SSA, including affected populations, transmission routes, and the zoonotic reservoirs. In addition, the review synthesized evidence on the public health, medical, and ecological interventions implemented during outbreaks and assessed the extent to which One Health integration across detection, surveillance, and response activities.

Additional outcome

Additional outcomes included synthesizing key findings reported in each outbreak study, which provided insight into patterns of zoonotic virus emergence, response strategies, and epidemiological characteristics specific to Sub-Saharan Africa.

Eligibility criteria

  1. Primary articles that reported on viral zoonotic disease outbreaks.

  2. Studies conducted in any of the Sub-Saharan African countries.

  3. Studies published between the years 2005 and 2025.

  4. Outbreak investigation studies, cross-sectional studies, case-report studies, and retrospective studies.

  5. Grey literature from recognized public health organizations including WHO and Africa CDC.

Study inclusion

Two independent investigators, SA and JMG used the eligibility criteria to select studies for inclusion in the review. Any disagreement was resolved by discussion, and/or a third reviewer, PED was consulted for a consensus to be reached.

Data extraction

We extracted the following data: title, author(s), publication year, study type, study country, outbreak year(s), zoonotic virus identified, zoonotic source / reservoir, transmission pattern (e.g., direct contact, vector-borne, airborne), affected population, prevalence / outbreak magnitude, number of deaths, reported risk factors, public health / medical / ecological intervention(s), intervention outcomes / effectiveness, integration of one health approach, surveillance / detection mechanisms, and key findings / notes. Mendeley Desktop Version 1.19.8 was used to identify duplicate records.

Data analysis and synthesis

The extracted data on zoonotic virus outbreaks including prevalence estimates, transmission patterns, and affected populations were summarized in tabular form. Information related to the type of zoonotic virus, human and animal case numbers, and reported intervention strategies was compiled and analyzed descriptively.

Risk of bias (quality) assessment

Consistent with existing methodological guidance for scoping reviews, a formal risk of bias assessment or quality appraisal was not undertaken for the included studies [23].

Results

Study selection procedures

We identified 4,523 records; after deduplication, 4,470 were screened by title/abstract. 56 articles underwent full-text assessment, and 41 met inclusion criteria. An additional 11 outbreak reports from organizational websites were included, yielding 52 studies overall (Fig. 1).

Fig. 1.

Fig. 1

PRISMA Flow diagram of the study selection procedure

Characteristics of included studies

Table 1 provides an overview of the 52 studies included in this scoping review, organized chronologically by the year in which each outbreak occurred. The 52 included items comprised peer-reviewed articles, outbreak investigations, national surveillance summaries, and situation reports from 25 sub-Saharan African countries (2006–2025). Most reports originated from East and West Africa, with frequent contributions from Uganda, Nigeria, Sudan, and Kenya. The majority focused on human outbreaks (n = 46); two reported on both humans and animals.

Table 1.

Characteristics of included studies according to the year of outbreak (2006–2025)

Author Year Country Outbreak Year Identified virus Study populations Study design
Bbosa et al. 2025 Uganda 2024 Mpox Clade Ib Humans Case reports and molecular analysis
Sabushimike et al. 2025 Burundi 2024 Mpox Humans Case report
Africa CDC 2024 Rwanda 2024 Marburg Humans Outbreak situation report
Africa CDC 2024 South Africa 2024 Mpox Humans Outbreak situation report
Masirika et al. 2025 DRC 2023–2024 Mpox Clade Ib Humans Observational study
Onukak et al. 2023 Nigeria 2023 *Mpox and (VZV) Humans Case Report
Africa CDC 2023 Tanzania 2023 Marburg Humans Outbreak situation report
Africa CDC 2023 Equatorial Guinea 2023 Marburg Humans Outbreak situation report
Zerfu et al. 2024 Ethiopia 2022–2023 CHIKV Humans Institution-based cross-sectional study
Tabassum et al. 2023 Mauritania 2022 RVFV Humans Outbreak report
Ishema et al. 2024 Rwanda 2022 RVFV Animals Outbreak investigation report
Mmerem et al. 2024 Nigeria 2022 *Mpox and (VZV) Human Case report
Ramera et al. 2024 Rwanda 2022 RVFV Animals Outbreak report
Musoke et al. 2023 Uganda 2022 Sudan Virus Humans Case report
Ogoina & James 2022 Nigeria 2022 Mpox Humans Case report
WHO 2022 Ghana 2022 Marburg Humans Outbreak situation report
WHO 2022 DRC 2022 Ebola Humans Outbreak situation report
Besombes et al. 2023 CAR 2021–2022 Mpox Clade I Human Outbreak investigation report
Keita et al. 2022 Guinea 2021 *LASV and SARS-CoV-2 Humans Case report
Africa CDC 2021 Guinea 2021 Marburg Humans Outbreak situation report
Barry et al. 2022 Mauritania 2020 RVFV Humans and animals Outbreak investigation
Fourié et al. 2021 Djibouti 2019 CHIKV Human Case Report with molecular characterization
Atim et al. 2023 Uganda 2019 CCHFV Humans and animals Outbreak investigation
Ahmed et al. 2021 Sudan 2019 CCHFV Humans Case series and molecular diagnostic investigation
Mirembe et al. 2021 Uganda 2018–2019 CCHFV Humans Epidemiological investigation and case-control study
Fusade-Boyer et al. 2019 Togo 2018 Inf A H5N1 Animals Outbreak investigation and molecular epidemiology study
Kayiwa et al. 2019 Uganda 2017 CHIKV and DENV Humans Case report
Yinka-Ogunleye et al. 2018 Nigeria 2017 Mpox West African Clade Humans Outbreak investigation report
Nyakarahuka et al. 2019 Uganda 2017 Marburg Humans Epidemiological and laboratory investigation
Yaro et al. 2021 Nigeria 2017–2020 LASV Humans Retrospective epidemiological analysis using national surveillance data from December 2016 to September 2020
Eltvedt et al. 2020 DRC 2016 Mpox Human Case report
Dokubo et al. 2018 Liberia 2015 Ebola virus Humans Case investigation
Christie et al. 2015 Liberia 2015 Ebola virus Human Case report and epidemiological investigation
Balinandi et al. 2018 Uganda 2015 CCHFV Humans Case investigation and outbreak response
Chérif et al. 2017 Guinea 2014–2015 Ebola virus Humans Nationwide retrospective cohort study
Bonney et al. 2018 Ghana 2014–2015 DENV 2 and 3 Humans Cross-sectional surveillance study using serological and molecular assays (retrospective)
Dunn et al. 2016 Sierra Leone 2014 Ebola virus Human Outbreak investigation
Nyakarahuka et al. 2017 Uganda 2014 Marburg virus Human Case Report
Ka et al. 2017 Senegal 2014 Ebola virus (Zaire) Humans Case report and outbreak investigation
WHO 2014 Guinea 2014 Ebola virus Humans Outbreak surveillance & response report
Liberia
Sierra Leone
Mali
Nigeria
Shoemaker et al. 2012 Uganda 2011 Sudan virus Humans Case report and outbreak investigation
Konongoi et al. 2016 Kenya 2011–2014 DENV 1–3 Humans Cross-sectional outbreak investigation
Ahmed et al. 2022 Sudan 2010, 2011, 2015, 2019, 2020 RVFV Humans Retrospective epidemiological study
Aradaib et al. 2010 Sudan 2008 CCHFV Humans Outbreak investigation and case series
Adjemian et al. 2011 Uganda 2007 Marburg Humans Outbreak investigation and case series
Chengula et al. 2014 Tanzania 2006–2007 RVFV Animals Cross-sectional sero-epidemiological study
Nguku et al. 2010 Kenya 2006–2007 RVFV Humans Epidemiological investigation combining surveillance data, serosurveys, and laboratory diagnostics
Peyrefitte et al. 2007 Cameroon 2006 CHIKV Humans Outbreak investigation
WHO 2025 Kenya 2006–2007 RVFV Humans Outbreak situation report
Somalia 2006–2007
Tanzania 2007
Sudan 2007–2008
Madagascar 2008
Madagascar 2008–2009
South Africa 2010
Mauritania 2012
Niger 2016
WHO 2017 Uganda 2007 Marburg Humans Outbreak situation report
2008
2012
2014
2017
WHO 2016 Kenya 2016 CHIKV Humans Outbreak situation report
Senegal 2015

CAR: Central African Republic

DRC: Democratic Republic of Congo

CCHFV: Crimean Congo Haemorrhagic Fever Virus

CHKIV: Chikungunya Virus

DENV: Dengue Virus

VZV: Varicella Zoster Virus

*: Co-infection

Epidemiological patterns reported by included studies

The most frequently reported viral zoonoses were Ebola virus, Mpox, Rift Valley fever virus (RVFV), and Marburg virus. Outbreak sizes ranged from isolated index cases to large-scale epidemics. The 2014 West Africa Ebola outbreak included > 18,000 cases and > 6,000 deaths, while the 2023–2024 Mpox outbreak in DRC involved > 600 cases. Case fatality rates varied: Ebola virus disease 25–90%, Marburg virus 33–50%, CCHFV up to 75%, and Mpox generally < 10%. Common risk factors included direct animal contact, vector exposure, bushmeat handling, and nosocomial transmission (Table S1; Supplementary File 1). Figure 2 illustrates the geographic distribution of reported viral zoonotic outbreaks, revealing clusters primarily in East and West Africa, which appear to be recurrent hotspots for zoonotic spillover or emergence. Across studies, common risk factors included contact with infected animals or animal products, vector exposure, and behaviors such as bushmeat handling. These findings highlight geographic and behavioral patterns that may inform targeted interventions.

Fig. 2.

Fig. 2

Geographic distribution of reported zoonotic virus occurrence in SSA

Transmission patterns

This included studies that identified a range of transmission modes associated with zoonotic viruses, with human-to-human transmission via direct contact being the most commonly reported. This was evident in outbreaks involving filoviruses such as the Marburg virus and the Ebola virus, where transmission occurred through close physical contact with infected individuals or their bodily fluids within households and healthcare settings. Other studies also reported nosocomial transmission, which were linked to insufficient use of personal protective equipment (PPE) and inadequate infection prevention and control (IPC) practices.

Transmission through sexual contact was highlighted as a potential route in a few of the studies, particularly during outbreaks of Mpox and Ebola virus disease [2427]. Monkeypox cases reported in Nigeria, DR Congo, and South Africa included individuals with genital lesions and anal proctitis, with histories of recent unprotected sexual encounters, suggesting sexual transmission as a key mode of spread in certain contexts [24, 26, 27]. The reported Ebola virus transmission through sexual contact with a convalescent male patient highlights the risk of viral persistence in semen after clinical recovery.

Other transmission routes reported by the included studies were vector-borne transmission and zoonotic spillover from wildlife [2834]. Outbreaks of Rift Valley Fever virus and Dengue virus were typically linked to vector-borne transmission through mosquitoes, while Crimean–Congo hemorrhagic fever (CCHFV) was associated with tick-borne transmission [28, 3438]. For example, RVFV outbreaks often followed periods of heavy rainfall that favored mosquito proliferation. Studies on Lassa fever and Marburg virus outbreaks reported zoonotic spillover from wildlife to humans, with Mastomys natalensis rodents serving as the primary reservoir for Lassa virus, and Rousettus aegyptiacus bats for Marburg virus [30, 3942].

Outbreak magnitude and case fatality rates

The magnitude of viral zoonotic outbreaks reported across the included studies ranged from isolated index cases to large-scale epidemics affecting human and animal populations. The 2024 Marburg virus outbreak in Rwanda involved 27 confirmed cases and 9 deaths, while the Mpox outbreak in the Democratic Republic of Congo (DRC) documented 646 cases and 7 deaths, predominantly among sex workers [27, 43]. Outbreaks of Rift Valley Fever virus (RVFV) was mostly zoonotic in nature, with one study reporting 78 human cases alongside 186 confirmed animal infections [34]. Additionally, the 2014 West Africa Ebola outbreak, documented by WHO [44], is one of the most severe zoonotic viral outbreaks, with over 18,000 cases and more than 6,000 deaths across five countries.

Case fatality rates (CFRs) significantly varied across virus types and settings. The Ebola virus disease outbreak reported by WHO [45] showed CFRs as high as 62.9% among paediatric cases. Depending on the setting and healthcare response, Marburg virus outbreaks reported CFRs ranging from 33% to over 50%. CCHFV was associated with CFRs of up to 75%, particularly in small outbreaks with delayed diagnosis. Monkeypox generally exhibited lower mortality; however, fatal outcomes were documented in immunocompromised individuals, particularly those co-infected with HIV.

Effectiveness of public health, medical, and ecological interventions

A variety of interventions were documented across the included studies in response to zoonotic viral outbreaks, as summarized in Table S2 (Supplementary File 2). These interventions comprised case detection and isolation, contact tracing, health education, vector control, and ecological or livestock-focused measures. These reflect varied approaches depending on the virus, setting, and available public health infrastructure. For MARV outbreaks reported in Ghana and Equatorial Guinea, the deployment of rapid response teams, contact tracing, and laboratory confirmation were central components of outbreak control [46, 47].

Mpox outbreaks, including a large outbreak in the Democratic Republic of Congo with over 600 cases, involved interventions focused on community sensitization, surveillance, and clinical management, especially among vulnerable populations such as sex workers and people living with HIV [27]. Despite these efforts, several studies reported persistent challenges related to delayed case recognition, and limited access to health services, which may have constrained the impact of public health interventions. In the Rift Valley Fever virus (RVFV) case, both medical and ecological measures were implemented. Interventions in Mauritania, Rwanda, and Kenya included livestock movement restrictions, vector control, animal health surveillance, and public awareness campaigns targeting high-risk occupational groups [28, 29, 33, 48].

Similarly, CCHFV outbreaks prompted tick control programs, public health awareness, and enhanced surveillance for healthcare and veterinary workers. In Uganda, occupational exposure among farmers and abattoir workers was noted, with response strategies tailored to high-risk communities [36, 38]. However, intervention outcomes were often sketchy, with few studies employing formal monitoring or impact evaluation. Although several studies reported successful containment following the deployment of control measures, a consistent gap across the literature was the absence of rigorous outcome evaluation. Most interventions were described narratively, with few studies providing quantitative data on effectiveness, such as incidence reduction, or speed of containment. These findings highlight the critical role of integrated public health, clinical, and ecological interventions in controlling zoonotic virus outbreaks. They also underscore the need for improved monitoring and evaluation frameworks to assess intervention effectiveness in real time. Future outbreak responses would benefit from adopting One Health strategies that combine human, animal, and environmental health approaches with robust data collection systems to inform policy and practic.

Integration of the One Health approach by included studies

The One Health approach, emphasizing the interconnectedness of human, animal, and environmental health was explicitly reported in only a limited number of the included studies. While zoonotic viruses inherently require multisectoral coordination, only four (7.7%) studies mentioned active integration of One Health principles in outbreak detection, surveillance, or response activities. In outbreaks reported by Ishema et al. (2024), Nguku et al. (2010) and Remera et al. (2024), the One Health approach was operationalized through coordinated response involving veterinary, public health, and environmental sectors. This included joint human and animal surveillance, integrated laboratory diagnostics, and multisectoral field investigations. Specifically, Ishema et al. (2024), Nguku et al. (2010) and Remera et al. (2024) documented district-level collaboration and RT-PCR testing in livestock during Rwanda’s 2022 RVF outbreak; Ishema et al. (2024), Nguku et al. (2010) and Remera et al. (2024) detailed concurrent entomological, human, and livestock surveillance during Kenya’s 2006–2007 RVF outbreak; and by Ishema et al. (2024), Nguku et al. (2010) and Remera et al. (2024) highlighted decentralized outbreak response teams, environmental risk mapping, and cross-sector sample tracking as key elements of the operational One Health strategy.

In another study by Barry et al. (2022), the One Health approach was fully implemented during the outbreak with coordinated weekly meetings across all sectors. In contrast, majority (48/52; 92.3%) of included studies, particularly those focusing on human clinical cases (12/52) or hospital-based surveillance (9/52), did not mention involvement of veterinary or ecological health sectors, where such multisectoral integration was relevant. Moreover, while zoonotic reservoirs (e.g., livestock, rodents, bats) were discussed in many studies, corresponding surveillance or intervention measures targeting these reservoirs were seldom integrated into outbreak response plans. Although 48 (92.3%) studies did not explicitly reference the use of a One Health approach, strategy elements may have been implemented but not expressly documented in the published reports. The findings highlight a critical implementation gap between One Health theory and practice. Although zoonotic virus outbreaks demand a multidisciplinary response, integrating human, animal, and environmental health responses remain rarely documented and underreported in the literature. Strengthening One Health capacity at the national and regional level through formal frameworks, multisectoral coordination mechanisms, and joint outbreak investigations remains a pressing need for improving preparedness and response to emerging zoonoses in Sub-Saharan Africa. Table 2 summarises the integration of the one health approach by the included studies.

Table 2.

Integration of One Health approach by included studies

Author(s) Integration of one health approach Surveillance / detection mechanisms
Masirika et al. Not stated Genomic sequencing; epidemiological data collection; contact tracing
Tabassum et al. Not stated Laboratory confirmation of cases; monitoring of animal and human cases
Dokubo et al. Not explicitly applied but survivor monitoring aligns with One Health principles Laboratory testing (RT-PCR), contact tracing
Kayiwa et al. Not stated Arbovirus surveillance at Uganda Virus Research Institute (UVRI); diagnostic testing including ELISA, RT-PCR, virus isolation
Ishema et al. Yes; coordinated response involving veterinary, public health, and environmental sectors Active surveillance; laboratory testing (RT-PCR); community reporting systems
Yinka-Ogunleye et al. Not stated Laboratory testing of blood, lesion swabs, and crusts; epidemiological investigations
Mmerem et al. Not stated PCR confirmation of Mpox and chickenpox; wound swab microscopy and culture
Besombes et al. Not stated Laboratory confirmation via PCR testing; clinical assessments; monitoring of contacts
Fusade-Boyer et al. Partially — collaboration among veterinary and lab agencies PCR confirmation, genome sequencing, phylogenetic analysis
Peyrefitte et al. Not discussed Laboratory testing (RT-PCR, serology, virus isolation); patient monitoring
Remera et al. Yes – coordinated cross-sectoral response involving public health, veterinary, and community actors Syndromic surveillance, molecular diagnostics (PCR), national laboratory support
Fourié et al. Not discussed RT-PCR and full genome sequencing
Dunn et al. Not stated Medical record review, interviews with healthcare workers and caregivers, daily monitoring of contacts for EVD symptoms
Eltvedt et al. Not stated Clinical diagnosis based on symptoms; delayed serological testing; no PCR confirmation due to logistical challenges
Christie et al. Not stated Lab confirmation (RT-PCR), semen testing, contact tracing
Bbosa et al. Not stated PCR testing, genomic sequencing, phylogenetic analysis
Atim et al. Not stated ELISA for antibody detection; qRT-PCR and next-generation sequencing for virus detection in ticks
Nyakarahuka et al. Not explicitly mentioned Real-time RT-PCR, antigen detection, IgM ELISA, virus isolation, whole-genome sequencing
Konongoi et al. Not explicitly mentioned RT-PCR, IgM ELISA, sequencing of PCR-positive samples
Musoke et al. Not stated Real-time PCR testing for SUDV
Chengula et al. Not stated RVF-specific inhibition ELISA (I-ELISA); Reverse transcription polymerase chain reaction (RT-PCR)
Chérif et al. Not stated National coordination; RT-PCR lab confirmation for all included cases
Nguku et al. Yes; collaboration among human health, animal health, and environmental sectors Patient interviews and medical record reviews, Community engagement for case detection, Laboratory confirmation via ELISA and RT-PCR, Establishment of field laboratories for sample processing
Yaro et al. Not stated Use of national surveillance data from the Nigeria Centre for Disease Control (NCDC), Laboratory confirmation of cases using RT-PCR, Deployment of the Surveillance Outbreak Response Management and Analysis System (SORMAS)
Ahmed et al., 2021 Not stated Blood samples from patients were tested using real-time qPCR for RVFV, dengue virus (DENV), and chikungunya virus (CHIKV)
Shoemaker et al. Not mentioned Laboratory confirmation using real-time PCR, Epidemiological investigation and contact tracing
Zerfu et al. Not stated Blood samples were collected and tested for anti-CHIKV IgM and IgG antibodies using enzyme-linked immunosorbent assay (ELISA), Microscopy was used to examine blood films for Plasmodium infection
Balinandi et al. Not stated Laboratory confirmation using RT-PCR and serological assays, Field investigations and tick sampling, Genomic sequencing to determine virus lineage
Konongoi et al. Not stated Samples collected from febrile patients in hospitals across Nairobi, northern, and coastal Kenya, Testing for IgM antibodies against dengue, yellow fever, West Nile, and Zika viruses using ELISA, Detection of acute arbovirus infections and determination of infecting serotypes using RT-PCR, Sequencing of representative PCR-positive samples to confirm circulation of dengue serotypes
Onukak et al. Not stated Polymerase Chain Reaction (PCR) testing of skin lesion samples, confirming co-infection with Mpox and VZV
Aradaib et al. Not stated Reverse transcription–PCR (RT-PCR) was used to detect CCHFV RNA in serum samples from eight patients, Phylogenetic analysis identified the virus as belonging to group III lineage, indicating links to strains from South Africa, Mauritania, and Nigeria
Adjemian et al. Not stated Laboratory confirmation of Marburg virus infection, Epidemiologic investigation to identify source and transmission patterns
Bonney et al. Not mentioned Serological testing using ELISA, Molecular testing using RT-PCR, Phylogenetic analysis of the envelope gene of DENV-3, showing close homology with sequences from Senegal and India
Sabushimike et al. Not mentioned Clinical evaluation, Laboratory confirmation of Mpox and HIV infections
Ka et al. Not mentioned Laboratory confirmation via reverse transcription PCR (RT-PCR). Epidemiological investigation
Keita et al. Not mentioned Reverse transcriptase PCR (RT-PCR) testing for SARS-CoV-2 and Lassa virus. EVD ruled out through negative PCR testing. Biochemical and haematological analyses to assess organ function
Ahmed et al. Not mentioned Laboratory confirmation through RT-PCR and serological assays; epidemiological investigations
Nyakarahuka et al. Not explicitly mentioned; however, ecological investigations were conducted to identify potential sources of infection RT-PCR testing for Marburg virus. Serological assays (IgM and IgG). Genome sequencing of viral isolates
Mirembe et al., 2021 Not implemented but recommended RT-PCR testing for CCHFV. Case-control study to identify risk factors
Ogoina & James Not mentioned Clinical observation of symptoms. Laboratory testing for Mpox virus
Barry et al. Yes — fully implemented during the outbreak with coordinated weekly meetings across sectors Laboratory confirmation (RT-PCR and serology in humans and animals). Vector surveillance and mosquito species identification. Epidemiological data collection and case mapping
WHO Not stated RT-PCR testing, WHO Integrated Disease Surveillance
Africa CDC Not stated Contact tracing, regional surveillance, expert deployment from Africa CDC
Africa CDC Not stated PCR confirmation; contact tracing and active case search
Africa CDC Not stated Lab confirmation by Institute Pasteur (Senegal); contact tracing and surveillance initiated
Africa CDC Not stated Testing and active monitoring
Africa CDC Not stated Confirmed at NICD, contact monitoring for 21 days, genomic sequencing done
WHO Not stated Active contact tracing, laboratory diagnostics in all affected districts, community surveillance, healthcare worker monitoring
WHO Not stated Not stated
WHO Not stated Laboratory confirmation at UVRI; active case search
WHO Not stated Not stated
WHO Not stated Lab confirmation (INRB & ETC), contact tracing,

Discussion of key findings

This scoping review synthesizes evidence on viral zoonotic outbreaks in sub-Saharan Africa (SSA) from 2005 to 2025, describing the diversity of pathogens, geographic distribution, transmission dynamics, response strategies, and the extent to which One Health approaches have been applied. Across 52 items from 25 SSA countries, the most frequently reported pathogens were RVFV, MARV, Mpox virus, Ebola virus, LASV, and CCHFV. Outbreak responses commonly included case detection/isolation, contact tracing, community engagement, vector control, livestock measures, and laboratory confirmation; however, standardized outcome metrics were seldom reported. Explicit use of One Health was rare and unevenly documented.

Outbreaks clustered in East and West Africa and reflected diverse transmission routes: human-to-human contact (notably filoviruses in households and health facilities, with nosocomial spread), vector-borne transmission (mosquitoes for RVFV and dengue; ticks for CCHFV), and zoonotic spillover (e.g., Rousettus aegyptiacus for MARV; Mastomys natalensis for LASV). Seasonality was prominent for RVFV (post-rainfall amplification), with site-specific deviations (e.g., dual seasonality in Rwanda), suggesting additional socio-ecological drivers such as livestock mobility and climate variability [33]. Many reports implicated reservoirs or vectors but lacked confirmatory entomological or animal data, limiting species-specific control options and risk-based targeting [49]. Re-emergence patterns for Mpox and sporadic co-infections (e.g., LASV/SARS-CoV-2) illustrate evolving risk profiles in interconnected human–animal ecologies.

Core response activities, rapid case identification, isolation, contact tracing, and risk communication, were widely implemented, with additional vector control and livestock movement restrictions for arboviral and haemorrhagic fever events. MARV responses in Ghana and Equatorial Guinea leveraged rapid response teams and surveillance. RVFV responses in Mauritania and Rwanda combined veterinary and vector measures. Nevertheless, reporting on effectiveness was inconsistent, few studies quantified incidence reduction, time-to-containment, reproduction number changes, or excess-risk attenuation [50]. Identified barriers included delayed recognition, limited diagnostics, under-resourced facilities, and IPC gaps, especially early in outbreaks and in nosocomial settings [51]. Differential impacts were noted in vulnerable groups (e.g., sex workers, immunocompromised individuals in Mpox clusters), underscoring the need for contextualized risk communication and service accessibility [27, 52].

Although zoonoses inherently demand multisectoral action, only a small fraction of the studies explicitly operationalized One Health (≈ 7.7%), typically during RVFV events integrating joint human–animal surveillance, cross-sector field investigations, and molecular diagnostics. Most reports mentioned reservoirs without corresponding veterinary or ecological interventions, indicating an implementation and documentation gap. Institutionalizing cross-sector frameworks, interoperable data systems, and shared field protocols, consistent with Quadripartite (WHO–WOAH–FAO–UNEP) guidance, remains a central unmet need [53].

Observed trends are consistent with broader literature: ecological factors (rainfall anomalies, flooding, land-use change), social or behavioural risks (bushmeat handling, caregiving or burial practices, unprotected sexual contact), and structural determinants (urban density, mobility, health-system capacity) jointly shape spillover and amplification [54, 55]. Political determinants, including governance stability, leadership commitment, coordination, and public trust, also influence outbreak dynamics; strong political will and cross-sectoral collaboration enable early detection and control, whereas weak governance, insecurity, and poor coordination prolong transmission and elevate case-fatality rates [56, 57]. Compared with high-income settings, SSA outbreaks more frequently encounter diagnostic delays, supply constraints, and IPC gaps, which can elevate CFRs, particularly for filoviruses and CCHFV, while Mpox CFRs remain lower but increase in immunocompromised populations. Where integrated surveillance and rapid diagnostics are available, containment is faster and secondary transmission is reduced, mirroring gains seen in other regions.

Policy and research implications of these findings are clear. Strengthening preparedness requires the institutionalization of One Health at national and subnational levels through mandated joint surveillance, co-financed veterinary and public health operations, and shared laboratory and data systems. Event-based and community surveillance should be reinforced with real-time data flows and feedback loops to local responders, while entomological and animal reservoir surveillance must be scaled up to enable species-specific vector and tick control and targeted livestock measures. Standardized response metrics, including the reproduction number, time to isolation, days to laboratory confirmation, attack rate, and case fatality rates stratified by context, are urgently needed for comparative evaluation across outbreaks. Parallel investment is necessary to expand surge diagnostic capacity and infection prevention and control, including rapid testing, protective equipment, and isolation capacity, combined with tailored risk communication for high-risk and marginalized populations. In addition, the integration of climate and mobility analytics, such as rainfall anomalies, droughts, or pastoralist movements, into predictive models would enhance early warning and pre-emptive controls. Finally, building interoperable data systems across human, animal, and environmental health sectors, in line with Quadripartite guidance, is critical for strengthening coordinated preparedness and response.

This review has several limitations. From the initial 228,000 Google and 843,000 Google Scholar results, only the first 100 and 200 articles, respectively, were screened, following established rapid appraisal methods for large databases, which may have led to omission of some relevant studies [21]. We prioritized breadth over critical appraisal; consistent with guidance, we did not perform formal risk-of-bias assessments [23]. Grey literature and situation reports may vary in completeness and verification. To mitigate this, we triangulated across multiple sources where available. Language restrictions (English-only) and the 2005–2025 window may exclude relevant evidence. Heterogeneity in outbreak definitions, case ascertainment, and reporting limited quantitative synthesis. We addressed this by presenting standardized summary tables and narratively synthesizing patterns rather than pooling estimates. Limited documentation of intervention outcomes constrained inferences about effectiveness. Some relevant outbreak reports, particularly recurrent Ebola virus investigations in the Democratic Republic of the Congo, may not have been captured due to their dissemination through grey literature or non-indexed sources. Future studies should report comparable metrics to enable cross-setting evaluation.

Conclusion

Viral zoonotic outbreaks continue to pose a major public health threat in SSA, reflecting the interplay of ecological, socio-economic, and behavioural drivers at the human, animal, environment interface. This review shows that, despite progress in outbreak detection and response, critical weaknesses persist in surveillance, preparedness, and cross-sector coordination. Early detection must be reinforced through community-based and event-driven surveillance linked to rapid laboratory confirmation, while health system capacity for diagnostics, IPC, and emergency logistics requires further investment.

Scaling up the One Health approach is central to improving preparedness. This involves not only policy endorsement but also practical mechanisms for multisectoral collaboration, joint outbreak investigations, integrated data systems, and sustainable funding. More systematic application of One Health principles will strengthen early warning and enhance coordinated responses. At the same time, operational research is needed to evaluate interventions using standardized metrics, while ecological and longitudinal studies should be expanded to better understand spillover dynamics. Integrating climate and mobility analytics into predictive models will further support proactive outbreak control.

In summary, embedding a stronger and operationalized One Health framework into policy, practice, and research agendas is essential for reducing the risk and impact of future zoonotic pandemics in Africa.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary Material 1 (38.2KB, docx)
Supplementary Material 2 (28.9KB, docx)
Supplementary Material 3 (30.6KB, xlsx)
Supplementary Material 4 (15.4KB, docx)

Acknowledgements

We express our sincere appreciation to the German-West African Centre for Global Health and Pandemic Prevention (G-WAC) and the Berlin University Alliance (BUA) for providing both financial and technical support.

Author contributions

SA, PED, JMG, GA, AAS, RMD, WT, YAS, ROP, CD, MO made substantial contributions to the conception, design and write-up of this review. SA and JMG performed the screening, study selection and data extraction from all studies using the eligibility criteria. All authors approved the final version of this manuscript.

Funding

The work has been made possible by the German Academic Exchange Service (DAAD) through the German-West African Centre for Global Health and Pandemic Prevention (G-WAC) scholarship as part of the Global Centers Program funded by the German Federal Foreign Office. Additional financial support for supervision was made available by the Flattening the Curve Project of the Berlin University Alliance (BUA).

Data availability

No datasets were generated or analyzed during the current study.

Declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Footnotes

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References

Associated Data

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

Supplementary Materials

Supplementary Material 1 (38.2KB, docx)
Supplementary Material 2 (28.9KB, docx)
Supplementary Material 3 (30.6KB, xlsx)
Supplementary Material 4 (15.4KB, docx)

Data Availability Statement

No datasets were generated or analyzed during the current study.


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