Search

Background: Although the first year of the COVID-19 pandemic in Africa did not produce the expected catastrophe, the true impact of COVID-19 in the Cameroonian population was unclear. We therefore assessed the seroprevalence of anti-SARS-CoV-2 antibodies and retrospective mortality in a representative sample of the general population in the 10 administrative regions of Cameroon more than one year after the first confirmed cases of COVID-19 in these regions. We aimed to assess the extent of SARS-COV-2 infection and to detect potential increases in the crude mortality rate (CMR) during the SARS-COV-2 pandemic phase. Methods: We assessed retrospective mortality and seroprevalence of anti-SARS-CoV-2 antibodies in the 10 capital cities of Cameroon using representative samples of the general population. The study included nested anti-SARS-CoV-2 antibody prevalence surveys and retrospective mortality surveys and was conducted between 27 July 2021 and 31 August 2021. To further analyze crude mortality rates by age group and COVID wave, pre-pandemic and pandemic periods were stratified. Both laboratory-based assays (ELFA) and rapid diagnostic tests (RDT) were used to measure anti-SARS-CoV-2 seroprevalence. Results: The crude mortality rate (CMR) increased from 0.06 deaths per 10 000 persons per day (pre-pandemic) to 0.17 deaths per 10 000 persons per day (pandemic). The increase in CMR was more pronounced in people aged 20–35 years (pre-pandemic 0.02 deaths per 10 000 persons per day; pandemic 0.06 deaths per 10 000 persons per day). The estimated seroprevalence among unvaccinated persons was 9.5 % (RDT) and 15.4 % (laboratory-based). Conclusion: The seroprevalence results showed that cases were significantly underdetected by the national surveillance systems.

[This corrects the article DOI: 10.1371/journal.pone.0152310.].

The Central African Republic (CAR) is characterized by widespread HIV epidemic with notable prevalence and genetic diversity. We herein analysed the genetic diversity of atypical non-M HIV-1 strains. In-house serotyping assays for variants of HIV-1 (M, N, O, P) and HIV-2 were used to test a biological collection of 6092 HIV-seropositive blood samples collected between 2003 and 2014 at the Institut Pasteur de Bangui. Samples indicative of recombinant M/O groups, HIV-2, or those that yield doubtful/negative results underwent further PCR tests and sequencing. We found six atypical HIV strains: specifically, three (0.05%) HIV-1 group O strains (subtype H) detected in samples from 2005, 2008 and 2009, alongside three (0.05%) HIV-2 strains (two group A and one group B) identified in samples from 2007 and 2009. HIV-1/O strains showed a genetic link to Cameroon and Gabon strains. This study highlights the dominance of HIV-1/M in the CAR's HIV epidemic over time and underscores the infrequent occurrence of HIV-1 group O and HIV-2 strains. These findings validate the efficacy of WHO-recommended HIV testing protocols and emphasize the need for adaptive surveillance and management strategies to confront the complexities introduced by the genetic diversity of HIV strains., (© 2024 Scandinavian Societies for Pathology, Medical Microbiology and Immunology.)

On August 14, 2024, following a regional declaration by the Africa Centres for Disease Control and Prevention, the World Health Organization declared mpox a Public Health Emergency of International Concern, marking the second such declaration in two years. A series of outbreaks involving the more virulent clade I virus (compared to clade II, which caused a global outbreak in 2022), has now spread in 13 African countries, exposing the inadequacies of the public health infrastructure in these settings. There was significant investment during the 2022 global outbreak, but these efforts failed to address vaccine access and treatment in the Global South. Regulatory delays, unequal access to vaccines, and a lack of compassionate use treatments for severe cases have resulted in preventable cases and deaths, especially among vulnerable populations such as pregnant women, children, and the immunocompromised. The current outbreak also underscores critical knowledge gaps in our understanding of mpox, including its transmission, pathogenesis, and viral evolution. We join intensified calls for global solidarity and action to control mpox, emphasizing immediate containment measures and long-term local and international investment in African public health systems, to prevent future epidemics.

During the COVID-19 pandemic, the need for making testing readily available was recognized as an important factor for individuals to help make informed decisions, including to isolate or seek care, and for policymakers to control transmission. Toward this end, FIND and the Access to COVID-19 Tools Accelerator funded 16 rapid operational research studies and one implementation project in Africa, the Caribbean, and Asia evaluating the utility, acceptability, and feasibility of different community-based SARS-CoV-2 testing approaches. Here, we discuss common factors and challenges encountered during study implementation. We note six key factors essential for success: 1) collaboration and partnerships; 2) buy-in of local stakeholders, including communities; 3) access to affordable supplies; 4) flexible financing; 5) effective approval systems; and 6) a skilled and motivated workforce. We also note various challenges that must be addressed to fully capitalize on these success factors. In particular, ethics committees are often not well equipped to assess operational research during outbreaks. Outbreaks, especially of novel pathogens, are unpredictable, and transmission dynamics are even more likely to change if the pathogen is prone to frequent mutations, such as SARS-CoV-2. Research that aims to evaluate strategies for curbing transmission must hence be easily and swiftly adaptable. This requires flexibility from researchers, funders, staff conducting the studies, and ethics and other approval committees. International guidelines for evaluating operational research protocols in outbreaks are needed to provide timely evidence to enable informed decisions by individuals, communities, and policymakers, thereby reducing both the human and the economic impact of outbreaks.

While treatment options for hepatitis C virus (HCV) infection have expanded considerably over the past decade thanks to the development of pan-genotypic therapies, genotype testing remains a prerequisite for treatment in sub-Saharan African countries, including Cameroon, where multiple HCV genotypes and subtypes exist. The main objective of this study was to describe the trend in the distribution of HCV genotypes and subtypes from 2013 to 2023 in the Cameroonian population. Viral loads were determined using the Abbott real-time assay, and genotyping/subtyping was based on nested and semi-nested reverse transcription polymerase chain reaction (RT-PCR) amplification of the regions encoding the core and non-structural protein 5B (NS5B) regions, respectively, followed by sequencing and phylogenetic analysis. A total of 512 patients with NS5B and core sequencing results were included in our study. Genotyping revealed a predominance of both genotype 4 (38.48%) and genotype 1 (37.11%), followed by genotype 2, detected in 22.46% of patients. Interestingly, 10 samples (1.95%) had discordant genotypes in both regions, suggesting the presence of putative recombinant forms of HCV. Twelve different subtypes were detected during the study period, with a predominance of subtypes 4f (18.95%) and 1e (16.02%). Furthermore, phylogenetic analysis failed to assign a subtype to a relatively high proportion of sequences (38.67%) for the two genomic regions, and their classification was limited to genotype assignment. The frequency distribution of HCV genotypes did not show any statistical difference according to year or sex. These results confirm the genetic diversity of HCV in Cameroon and the potential for the generation of recombinant strains., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Background: Formal assessment of a surveillance system's features and its ability to achieve objectives is crucial for disease control and prevention. Since the implementation of the mpox surveillance system in Cameroon, no evaluation has been conducted., Methods: In a cross-sectional study, we assessed the performance of the mpox surveillance system in accordance with the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) guidelines. We collected mpox surveillance data from 2018 to 2022 and conducted a survey with key stakeholders of the surveillance program. The survey results were summarized. The rates of complete reporting and mpox detection, as well as the time lag between the different stages of surveillance were analyzed using R version 4.1., Results: The mpox detection rate was 21.6% (29/134) over the five years under review. Surveillance indicators revealed that a combination of sample types, including vesicles, crust, and blood, was associated with higher case confirmation. Overall, the mpox surveillance system was effective. Weaknesses in terms of simplicity were identified. Most components of the assessed system failed to meet the timeliness and data quality goals, except for the laboratory component, which was commendable. The lack of a computerized shared database and the system's non-sustainability were a course of concern., Conclusions: Despite all identified bottlenecks in the mpox surveillance system in Cameroon, it was found to meet it stipulated goals. Recommendations are made for training on surveillance system features, particularly at the facility/field level. Therefore, there is a crucial need to globally improve the mpox surveillance system in Cameroon for better disease control., (© 2024. The Author(s).)

Robust testing strategies are an essential aspect of COVID-19 pandemic preparedness and response. In 2022, most regions of Cameroon were still below the WHO's recommended level of 10 COVID-19 tests per 10,000 population. This study aimed to detect SARS-CoV-2 cases in university settings in Cameroon using antigen rapid diagnostic tests (Ag-RDTs) to increase national testing capacity and assess the knowledge, attitudes, and practices of this population regarding COVID-19 infection. Six universities in Buea, Douala, Dschang, Maroua, Ngaoundere, and Yaounde participated in this study from June to October 2022. Nasopharyngeal swabs were collected from participants and tested for COVID-19 using Ag-RDTs. For all positive cases, high-risk contacts were also tested by Ag-RDT. Participants were administered a structured questionnaire to assess their knowledge, attitudes, and practices regarding COVID-19. A total of 7,006 participants were recruited, and 54 (0.8%) were positive for SARS-CoV-2. Among close contacts, three of 62 (4.8%) tested positive. The University of Maroua was the only site to consistently report satisfactory testing capacity, achieving the study target of 30 tests/10,000 in 94.1% of cases. Participants' knowledge of COVID-19 was moderate to good (≥50%). However, 28% were unsure about the effectiveness of the COVID-19 vaccine. Two main factors were identified that could facilitate the spread of SARS-CoV-2 in university settings, namely the lack of restrictions on entering campus without a mask (36%) and the non-respect of social distancing on campus (42.7%). The results of this study will guide future policies to better control diseases with epidemic or pandemic potential by targeting educational institutions.

Background: Sub-Saharan African countries have a high burden of viral hepatitis and poor access to screening and care. The aim of this study was to evaluate the feasibility and acceptability of using the plasma separation card (PSC) for viral hepatitis B and C screening among people living with HIV (PLHIV) in Cameroon and Uganda., Methods: This is a cross-sectional study carried out between 05/2021 and 03/2023 including 192 PLHIV in Cameroon (n = 104) and Uganda (n = 88). Basic sociodemographic variables and whole blood samples were collected. Adequate filling with blood of PSCs was used to determine feasibility together with participant responses to questions on acceptability. A logistic regression model was carried out to assess the relationship between PSC acceptability and factors of interest., Results: 70% of participants reported PSC as an acceptable viral hepatitis screening tool, and it was significantly more accepted in Uganda than Cameroon (100% vs. 43.2%, p < 0.001). Similarly, 75% of PSCs had at least one spot sample filled and were viable for analysis, 99% were correctly filled in Uganda and 53.4% in Cameroon. Reported ease of method performance (aOR: 24.77 95% CI 2.97-206.42, p = 0.003) and reduced collection time (aOR: 3.73 95% CI 1.26-11.04, p = 0.017) were associated with greater odds of PSC acceptance. HBsAg + and anti-HCV + prevalence were 11.1% and 1.0%, respectively., Conclusions: In spite of country differences, overall, the PSC was reported as a feasible and acceptable viral hepatitis testing method. Acceptability and feasibility of the method must be explored in heterogeneous target communities and qualitative research to better understand country-specific barriers and facilitators should be carried out., (© 2024. The Author(s).)

Introduction: Community Advisory Boards (CABs) play an important role in developing and delivering patient-centered care. However, the impact of participation on CAB members has not been well studied, particularly on the global scale. In 2022, the Hepatitis B Foundation (HBF) convened the first global hepatitis B and hepatitis delta CAB with 23 members from 17 countries, representing six out of the seven World Health Organization (WHO) regions, and countries with the largest hepatitis B and hepatitis delta disease burden., Methods: To reflect on the process of assembling an effective and motivated CAB and assess the impact on CAB participants, three virtual focus group sessions were held with 16 participants in July and August 2023. Sessions were recorded and transcribed. Questions focused on motivations for joining the CAB, membership experiences, and lessons learned. Grounded theory analysis was used to generate hypotheses about reasons for CAB members' participation, as well as challenges and suggestions. Qualitative analysis using inductive reasoning identified key themes within responses. Transcripts were independently analyzed by a primary and secondary coder., Results: Motivations for joining the CAB included participants' desire to advocate for people living with hepatitis B and hepatitis delta, and other altruistic factors. Participants reflected that through CAB membership, they gained networking and advocacy opportunities and enhanced their hepatitis B- and hepatitis delta-related knowledge. Challenges participants experienced were related to time, physical limitations, and stigma. Finally, participants discussed their limited direct engagement with drug developers and proposed ways the CAB can increase interactions with stakeholders going forward., Discussion: Based on participants' assessments, establishing a global CAB for stigmatized infectious diseases is worth the effort. Regular internal review of community advisory boards' structure and performance is critical to ensure the CAB is fulfilling its mission., Competing Interests: The Hepatitis B Foundation receives public health program and research grants from BMS, GSK, Gilead Sciences and VBI Vaccines. Chari Cohen serves on a patient/advocacy advisory committee for GSK and Gilead Sciences, with funds being distributed to the Hepatitis B Foundation. Beatrice Zovich has also served on an advisory committee for Gilead for which she was financially compensated. Yasmin Ibrahim serves on a patient/advocacy advisory committee for Roche/Genentech, with funds being distributed to the Hepatitis B Foundation., (Copyright © 2024 Borondy-Jenkins, Ansah, Chen, Goldring, Ibrahim, Issa, Lesidrenska, Machado, Moore, Njouom, Okinedo, Racho, Scott, Zovich and Cohen.)

Background: The 2022 African Cup of Nations (AFCON) took place in Cameroon from January 9th to February 5th, 2022, including Garoua in the north. We aimed to measure the impact of this event on the local COVID-19 epidemic given the implementation of a preventive strategy based on a health pass., Methods: All players, staff and fans involved in the AFCON event were screened with PCR tests. Symptomatic cases were also continuously monitored in the general population and screened for variants of concern. Daily numbers of confirmed cases were compared to neighboring countries numbers retrieved from a public domain source., Results: In total, 1479 and 2481 tests were performed in the general population and on asymptomatic AFCON attendees, respectively. From the latter, 12.5% were PCR-positive; 97% were infected with Omicron, with no significant difference compared to the passive program (G-test, P value = 0.162). Surveillance indicated the AFCON did not increase the number of symptomatic PCR-positive cases in the general population compared to neighboring countries., Conclusions: Though the COVID-19 epidemic was fueled by asymptomatic cases infected with the Omicron variant at the time, the non-therapeutic preventive measures implemented for AFCON mitigated an increase in the epidemic in the local population., (© The Author(s) 2024. Published by Oxford University Press on behalf of Faculty of Public Health.)

Background: Ebola (EBOV) and Sudan (SUDV) orthoebolaviruses are responsible for lethal haemorrhagic fever outbreaks in humans in Central and West Africa, and in apes that can be at the source of human outbreaks for EBOV., Methods: To assess the risk of exposure to orthoebolaviruses through contact with non-human primates (NHP), we tested the presence of antibodies against different viral proteins with a microsphere-based multiplex immunoassay in a case-control study on bites from NHPs in forest areas from Cameroon (n=795), and in cross-sectional surveys from other rural populations (n=622) of the same country., Results: Seroreactivities against at least two viral proteins were detected in 13% and 12% of the samples for EBOV and SUDV, respectively. Probability of seroreactivity was not associated with history of NHP bites, but was three times higher in Pygmies compared to Bantus. Although no neutralizing antibodies to EBOV and SUDV were detected in a selected series of highly reactive samples, avidity results indicate strong affinity to SUDV antigens., Conclusion: The detection of high level of seroreactivities against orthoebolaviruses in rural Cameroon where no outbreaks have been reported, raises the possibilities of silent circulation of orthoebolavirus, or of other not yet documented filoviruses, in these forested regions., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

Objectives: Widespread testing and treatment are essential to eliminate hepatitis B virus (HBV) infection as a public health concern. However, in resource-limited countries, access to HBV PCR is limited. In this study, we developed a quantitative HBV PCR assay on open molecular platforms and evaluate its performance in diagnosing clinically significant HBV DNA thresholds as defined by the WHO (2000 IU/mL, 20 000 IU/mL, and 200 000 IU/mL)., Methods: We implemented our HBV PCR test in seven African and Asian countries and France, using either an in-house laboratory method or a European conformity for in vitro diagnostic (CE-IVD) marked version of the PCR (Generic HBV Charge Virale, Biocentric). Results were compared with reference tests (Roche Cobas AmpliPrep/Cobas TaqMan and Abbott RealTime on Abbott m2000)., Results: There was a good agreement between the HBV DNA results of 1015 samples tested by the PCR on open polyvalent platforms and the results from reference tests (mean difference (bias ± standard deviation [SD]): -0.3 ± 0.7 log 10 IU/mL and -0.2 ± 0.9 log 10 IU/mL when compared with Roche and Abbott tests, respectively). Kappa-Cohen agreements between the HBV PCR on open polyvalent platforms and the Roche/Abbott assays appeared almost perfect for HBV DNA levels ranged from >20 000 to 200 000 IU/mL and >200 000 IU/mL, substantial and moderate for HBV DNA levels ranged from 2000 to 20 000 IU/mL when compared with Abbott and Roche, respectively. The assay's performance was consistent across genotypes A, B, C, D, and E., Discussion: This field evaluation showed that our HBV PCR test is a valuable alternative to proprietary PCR systems. PCR assays on open platforms contribute to expanding clinical laboratory solutions for diagnosing individuals who meet the viral load criteria for antiviral therapy (>20 000 IU/mL) and mother-to-child prophylaxis (>200 000 IU/mL)., (Copyright © 2024. Published by Elsevier Ltd.)

Competing Interests: JBN is supported by the US National Institutes of Health (grant numbers NIH/FIC 1R25TW011217-01, NIH/FIC 1D43TW010937-01A1, NIH/FIC D43TW011827-01A1, NIH/FIC 1R21TW011706-0, and NIH/NIAID 5U01AI096299-13). FN and AZ are codirectors of the Pan-African Network on Emerging and Re-Emerging Infections funded by the European and Developing Countries Clinical Trials Partnership (EDCTP) within the EU Horizon 2020 Framework Programme. FN and AZ also acknowledge support from the EDCTP Central Africa Clinical Research Network. AZ is a UK National Institute for Health Research senior investigator, and a Mahathir Science Award and EU-EDCTP Pascoal Mocumbi Prize laureate. JJM-T holds National Institutes of Health National Institute of Allergy and Infectious Diseases grants (number 75N91019D00024-P00001-759102000025-5). JK is supported by grant funding from the Canadian Institutes of Health Research and International Development Research Centre (grant numbers MRR-184813 and PPE-185821). ELM is supported by the US National Institutes of Health (grant number 1R01AI182082-01). All other authors declare no competing interests. We thank John L Johnson for critical review and helpful advice. The views and conclusions in this Personal View are those of the authors and do not necessarily represent the views of their institutions.

Fundamental aspects of the epidemiology and ecology of Mycobacterium ulcerans (MU) infections including disease burden, host range, reservoir, intermediate hosts, vector and mode of transmission are poorly understood. Understanding the global distribution and burden of MU infections is a paramount to fight against Buruli ulcer (BU). Four databases were queried from inception through December 2023. After critical review of published resources on BU, 155 articles (645 records) published between 1987 and 2023 from 16 countries were selected for this review. Investigating BU in from old endemic and new emerging foci has allowed detection of MU in humans, animals, plants and various environmental samples with prevalence from 0 % up to 100 % depending of the study design. A case fatality rate between 0.0 % and 50 % was described from BU patients and deaths occurred in Central African Republic, Gabon, Democratic Republic of the Congo, Burkina Faso and Australia. The prevalence of MU in humans was higher in Africa. Nucleic Acid Amplification Tests (NAAT) and non-NAAT were performed in > 38 animal species. MU has been recovered in culture from possum faeces, aquatic bugs and koala. More than 7 plant species and several environmental samples have been tested positive for MU. This review provided a comprehensive set of data on the updates of geographic distribution, the burden of MU infections in humans, and the host range of MU in non-human organisms. Although MU have been found in a wide range of environmental samples, only few of these have revealed the viability of the mycobacterium and the replicative non-human reservoirs of MU remain to be explored. These findings should serve as a foundation for further research on the reservoirs, intermediate hosts and transmission routes of MU., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Background: Respiratory syncytial virus (RSV) is one of the major pathogens frequently associated with severe respiratory tract infections in younger children and older adults globally. There is an unmet need with a lack of routine country-specific databases and/or RSV surveillance systems on RSV disease burden among adults in most low- and middle-income countries, including Cameroon. We aim to estimate the adult RSV burden needed to develop a framework for establishing an RSV surveillance database in Cameroon., Methods and Analysis: A two-phase study approach will be implemented, including a literature review and a review of medical records. First, a systematic review of available literature will provide insights into the current burden of RSV in adults in Cameroon, searching the following databases: Global Health, PubMed, CINAHL, Embase, African Journal Online Library, Scopus, Global Index Medicus, Cochrane databases, and grey literature search. Identified studies will be included if they reported on the RSV burden of disease among Cameroonian adults aged ≥18 years from 1st January 1990 to 31st December 2023. A narrative synthesis of the evidence will be provided. A meta-analysis will be conducted using a random effect model, when feasible. Two co-authors will independently perform data screening, extraction, and synthesis and will be reported according to the PRISMA-P guidelines for writing systematic review protocols. Secondly, a retrospective cohort design will permit data analysis on RSV among adults in the laboratory registers at the National Influenza Center. Medical records will be reviewed to link patients' files from emanating hospitals to capture relevant demographic, laboratory, and clinical data. The International Classification of Diseases and Clinical Modifications 10th revision (ICD-10-CM) codes will be used to classify the different RSV outcomes retrospectively., Results: The primary outcome is quantifying the RSV burden among the adult population, which can help inform policy on establishing an RSV surveillance database in Cameroon. The secondary outcomes include (i) estimates of RSV prevalence among Cameroonian adult age groups, (ii) RSV determinants, and (iii) clinical outcomes, including proportions of RSV-associated morbidity and/or death among age-stratified Cameroonian adults with medically attended acute respiratory tract infections., Conclusions: The evidence generated from the two projects will be used for further engagement with relevant stakeholders, including policymakers, clinicians, and researchers, to develop a framework for systematically establishing an RSV surveillance database in Cameroon. This study proposal has been registered (CRD42023460616) with the University of York Center for Reviews and Dissemination of the International Prospective Register of Systematic Reviews (PROSPERO)., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Njuma Libwea et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: Global monitoring of severe acute respiratory syndrome related coronavirus 2 (SARS-CoV-2) genetic sequences and associated metadata is essential for coronavirus disease 2019 (COVID-19) response. Therefore, Sanger's partial genome sequencing technique was used to monitor the circulating variants of SARS-CoV-2 in Cameroon., Methodology: Nasopharyngeal specimen was collected from persons suspected of SARS-CoV-2 following the national guidelines between January and December 2021. All specimens with cycle threshold (Ct) below 30 after amplification were eligible for sequencing of the partial spike (S) gene of SARS-CoV-2 using the Sanger sequencing method., Results: During the year 2021, 1481 real time reverse transcriptase polymerase chain reaction (RT-PCR) SARS-CoV-2 positive samples were selected for partial sequencing of the S gene of SARS-CoV-2. Amongst these, 878 yielded good sequencing products. A total of 231 probable variants (26.3%) were identified. The variants were mainly represented by Delta (70.6%), Alpha (15.6%), Omicron (7.4%), Beta (3.5%), Mu (1.7%) and Gamma (0.4%). Phylogenetic analysis of the probable variants from Cameroon with reference strains confirmed that all prior and current variants of concern (VOC) clustered with their respective reference sequences., Conclusions: The surveillance strategy implemented in Cameroon, based on partial sequencing of the S gene enabled identification of the major circulating variants and provided information on the distribution of these variants, which contributed to implementing public health measures to control disease spread in the country., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2024 Chavely Gwladys Monamele, Serge Alain Sadeuh-Mba, Pauliana Vanessa Ilouga, Moïse Henri Y Moumbeket, Loique Landry E Messanga, Aristide Mounchili Njifon, Estelle L Madaha, Ripa M Njankouo, Paul Alain Tagnouokam-Ngoupo, Jules Brice M Tchatchueng, Mathurin Cyrille Tejiokem, Ronald Perraut, Sara Eyangoh, Richard Njouom.)

Human Parechoviruses (HPeVs) have rarely been considered in the virological investigation of Acute Flacid Paralysis (AFP) cases in Africa, where enteric infections are very common. This study investigated the prevalence and genetic diversity of HPeV in 200 children aged ≤ 15 years with AFP in Cameroon from 2018 to 2019. HPeVs were detected in their faecal RNA using 5'-untranslated real-time RT-PCR. Detected HPeVs were typed by phylogenetic comparison with homologous sequences from homotypic reference strains. Overall, HPeV RNA was detected in 11.0% (22/200) of the 200 stool samples tested. Twelve HPeVs were successfully sequenced and reliably assigned to HPeV-A1, A4, A5, A10, A14, A15, A17 and A18 genotypes. Phylogenetic analyses revealed a high genetic variability among the studied HPeVs, as well as between the studied HPeVs and their previously reported counterparts from Cameroon in 2014. These findings suggest that different HPeV genotypes co-circulate in Cameroon without documented epidemics., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Njile et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Globally, rotavirus infections are the most common cause of diarrhea-related deaths, especially among children under 5 years of age. This virus can be transmitted through the fecal-oral route, although zoonotic and environmental contributions to transmission are poorly defined. The purpose of this study is to determine the epidemiology of rotavirus in humans, animals, and the environment in Africa, as well as the impact of vaccination., Methods: We searched PubMed, Web of Science, Africa Index Medicus, and African Journal Online, identifying 240 prevalence data points from 224 articles between 2009 and 2022., Results: Human rotavirus prevalence among patients with gastroenteritis was 29.8% (95% confidence interval [CI], 28.1%-31.5%; 238 710 participants), with similar estimates in children under 5 years of age, and an estimated case fatality rate of 1.2% (95% CI, .7%-2.0%; 10 440 participants). Prevalence was estimated to be 15.4% and 6.1% in patients with nongastroenteritis illnesses and apparently healthy individuals, respectively. Among animals, prevalence was 9.3% (95% CI, 5.7%-13.7%; 6115 animals), and in the environmental water sources, prevalence was 31.4% (95% CI, 17.7%-46.9%; 2530 samples)., Discussion: Our findings highlight the significant burden of rotavirus infection in Africa, and underscore the need for a One Health approach to limiting the spread of this disease., Competing Interests: Potential conflicts of interest . All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Worldwide, human respiratory syncytial virus (HRSV) is a major cause of severe infections of the lower respiratory system, affecting individuals of all ages. This study investigated the genetic variability of HRSV during the COVID-19 outbreak in Yaoundé; nasopharyngeal samples positive for HRSV were collected from different age groups between July 2020 and October 2021. A semi-nested RT-PCR was performed on the second hypervariable region of the G gene of detected HRSV, followed by sequencing and phylogenetic assessment. Throughout the study, 40 (37.7%) of the 106 HRSV-positive samples successfully underwent G-gene amplification. HRSV A and HRSV B co-circulated at rates of 47.5% and 52.5%, respectively. HRSV A clustered in the GA2.3.5 genetic lineage (ON1) and HRSV B clustered in the GB5.0.5a genetic lineage (BA9). Differences in circulating genotypes were observed between pre- and post-pandemic years for HRSV A. Predictions revealed potential N-glycosylation sites at positions 237-318 of HRSV A and positions 228-232-294 of HRSV B. This study reports the molecular epidemiology of HRSV in Cameroon during the COVID-19 pandemic. It describes the exclusive co-circulation of two genetic lineages. These findings highlight the importance of implementing comprehensive molecular surveillance to prevent the unexpected emergence of other diseases.

Background: Influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are both respiratory viruses with similar clinical manifestations and modes of transmission. This study describes influenza data before and during the coronavirus disease pandemic (COVID-19) in Cameroon and SARS-CoV-2 data during the pandemic period., Methods: The study ran from 2017 to 2022, and data were divided into two periods: before (2017-2019) and during (2020-2022) the COVID-19 pandemic. Nasopharyngeal samples collected from persons with respiratory illness were tested for influenza using the Centers for Disease Control and Prevention (CDC) typing and subtyping assays. During the COVID-19 pandemic, the respiratory specimens were simultaneously tested for SARS-CoV-2 using the DaAn gene protocol or the Abbott real-time SARS-CoV-2 assay. The WHO average curve method was used to compare influenza virus seasonality before and during the pandemic., Results: A total of 6246 samples were tested. Influenza virus detection rates were significantly higher in the pre-pandemic period compared to the pandemic period (30.8% vs. 15.5%; p < 0.001). Meanwhile, the SARS-CoV-2 detection rate was 2.5%. A change in the seasonality of influenza viruses was observed from a bi-annual peak before the pandemic to no clear seasonal pattern during the pandemic. The age groups 2-4 and 5-14 years were significantly associated with higher influenza positivity rates in both pre-pandemic and pandemic periods. For SARS-CoV-2, all age groups above 15 years were the most affected population., Conclusion: The COVID-19 pandemic had a significant impact on the seasonal influenza by changing the seasonality of the virus and reducing its detection rates., (© 2024 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.)

Background: Hepatitis E virus (HEV) is a major cause of enterotropic viral hepatitis, a major public health problem in many developing countries. In Central African Republic (CAR), HEV genotypes 1, 2, and 3 have been found to have an impact on human health. However, data on HEV in animal reservoirs are still lacking for CAR. Here, we investigated the presence of HEV in farmed pigs and goats in Bangui, the capital city of CAR, using molecular methods., Methodology: In a prospective study, fecal samples from 61 pigs and 39 goats from farms in five districts (2nd, 4th, 6th, 7th, 8th) of Bangui were collected and tested for HEV RNA by real-time RT-PCR. The samples were further analyzed by nested-PCR and sequenced to determine the genotype and subtype to which the virus belong., Results: In total, 22/100 (22.0%) feces samples were successfully amplified for HEV RNA by real time RT-PCR. All positive samples were from pigs (22/61; 36.1%), while all goat samples were negative (0/39). Twelve HEV RNA samples (12/22 or 54.5%) were successfully amplified by nested RT-PCR, and subsequently sequenced. Phylogenetic analysis revealed that the obtained sequences clustered with subtype 3h and were genetically related to the human HEV sequences from CAR., Conclusion: This study confirms that pigs constitute an HEV reservoir, with genotype 3 being the major circulating strain. Further studies are needed to investigate other local reservoirs and to improve knowledge of the molecular epidemiology of HEV in CAR., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Nombot-Yazenguet et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

During 1979-2022, Cameroon recorded 32 laboratory-confirmed mpox cases among 137 suspected mpox cases identified by the national surveillance network. The highest positivity rate occurred in 2022, indicating potential mpox re-emergence in Cameroon. Both clade I (n = 12) and clade II (n = 18) monkeypox virus (MPXV) were reported, a unique feature of mpox in Cameroon. The overall case-fatality ratio of 2.2% was associated with clade II. We found mpox occurred only in the forested southern part of the country, and MPXV phylogeographic structure revealed a clear geographic separation among concurrent circulating clades. Clade I originated from eastern regions close to neighboring mpox-endemic countries in Central Africa; clade II was prevalent in western regions close to West Africa. Our findings suggest that MPXV re-emerged after a 30-year lapse and might arise from different viral reservoirs unique to ecosystems in eastern and western rainforests of Cameroon.

Introduction: Poliovirus (PV) and non-polio enteroviruses (NPEV) belong to the Picornaviridae family. They are found worldwide and are responsible for a wide range of diseases such as acute flaccid paralysis (AFP). This study aimed to evaluate the detection rate of PV and NPEV in stool samples from children under fifteen years of age presenting with AFP in Cameroon and their distribution over time., Methodology: Stool samples were collected as part of poliovirus surveillance throughout Cameroon from 2015 to 2020. Virus isolation was performed using RD and L20B cells maintained in culture. Molecular methods such as intratypic differentiation were used to identify PVs serotypes and analysis of the VP1 genome was performed., Results: A total of 12,354 stool samples were analyzed. The EV detection rate by virus isolation was 11.42% (1411/12354). This rate varied from year to year with a mean distribution of 11.41 with a 95% confidence interval [11.37; 11.44]. Of the viruses detected, suspected poliovirus accounted for 31.3% (442/1411) and NPEV 68.67% (969/1411). No wild poliovirus (WPV) was isolated. Sabin types 1 and 3 were continuously isolated. Surprisingly, from February 2020, vaccine-derived PV type 2 (VDPV2) was detected in 19% of cases, indicating its resurgence., Conclusions: This study strongly supports the successful elimination of WPV in Cameroon and the resurgence of VDPV2. However, as long as VDPV outbreaks continue to be detected in Africa, it remains essential to monitor how they spread., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2024 Daniel K Njile, Serge A Sadeuh-Mba, Michel Tabonfack Atemkeng, Anicet Ahanda, Jean Blaise Momo, Raissa Pekekue Nforifum, Ernestine Etéré, Marie Claire Endegue-Zanga, Onana Boyomo, Marlise D Djoumetio, Jude Anfumbom Kfutwah, Ousmane M Diop, Richard Njouom.)

Background: Febrile jaundice is a common indicator of certain infectious diseases, including hepatitis E. In Cameroon, the yellow fever virus is the only pathogen that is monitored in patients who present with this symptom. However, more than 90% of the samples received as part of this surveillance are negative for yellow fever. This study aimed to describe the prevalence and hepatitis E virus (HEV) genotype among yellow fever-negative patients in the Far North and West regions of Cameroon., Methods: In a cross-sectional study, yellow fever surveillance-negative samples collected between January 2021 and January 2023 were retrospectively analyzed. Anti-HEV IgM and IgG antibodies were tested using commercially available ELISA kits. Anti-HEV IgM and/or IgG positive samples were tested for HEV RNA by real-time RT-PCR, followed by nested RT-PCR, sequencing and phylogenetic analysis., Results: Overall, 121 of the 543 samples (22.3%, 95% CI: 19.0% - 26.0%) were positive for at least one anti-HEV marker. Amongst these, 8.1% (44/543) were positive for anti-HEV IgM, 5.9% (32/543) for anti-HEV IgG, and 8.3% (45/544) for both markers. A total of 15.2% (12/79) samples were positive for HEV RNA real-time RT-PCR and 8 samples were positive for HEV RNA by nested RT-PCR. Phylogenetic analysis showed that the retrieved sequences clustered within HEV genotypes/subtypes 1/1e, 3/3f and 4/4b., Conclusion: Our results showed that HEV is one of the causes of acute febrile jaundice in patients enrolled in the yellow fever surveillance program in two regions of Cameroon. We described the circulation of three HEV genotypes, including two zoonotic genotypes. Further studies will be important to elucidate the transmission routes of these zoonotic HEV genotypes to humans in Cameroon., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Modiyinji et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Dialysis is a replacement therapy for patients with End-Stage Renal Disease (ESRD). Patients on dialysis are at high risk of acquiring hepatitis C virus (HCV), which has become a leading cause of morbidity and mortality in this population. There is a wide range of prevalence of HCV in dialysis populations around the world. It is still unknown how prevalent HCV infection is among worldwide dialysis patients (including those undergoing hemodialysis and peritoneal dialysis). A review was conducted to estimate the global epidemiology of hepatitis C in dialysis patients. We searched PubMed, Excerpta Medica Database (Embase), Global Index Medicus and Web of Science until October 2022. A manual search of references from relevant articles was also conducted. Heterogeneity was evaluated by the χ2 test on Cochrane's Q statistic, and the sources of heterogeneity were investigated using subgroup analysis. In order to assess publication bias, funnel plots and Egger tests were conducted, and pooled HCV prevalence estimates were generated using a DerSimonian and Laird meta-analysis model. The study is registered with PROSPERO under CRD42022237789. We included 634 papers involving 392160 participants. The overall HCV case fatality rate was 38.7% (95% CI = 28.9-49). The global prevalence of HCV infection in dialysis population group were 24.3% [95% CI = 22.6-25.9]. As indicated by UNSD region, country, dialysis type, and HCV diagnostic targeted; Eastern Europe had the highest prevalence of 48.6% [95% CI = 35.2-62], Indonesia had 63.6% [95% CI = 42.9-82], hemodialysis patients had 25.5% [95% CI = 23.8-27.3], and anti-HCV were detected in 24.5% [95% CI = 22.8-26.2]. Dialysis patients, particularly those on hemodialysis, have a high prevalence and case fatality rate of HCV infection. Hemodialysis units need to implement strict infection control measures., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Kenfack-Momo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Healthcare workers (HWs) are at a high risk of exposure to emerging health threats. Following the first wave of the coronavirus disease 2019 pandemic in Cameroon, we explored the presence and persistence of naturally acquired antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the factors associated with seropositivity in HWs., Methods: Staff at two referral hospitals in Yaoundé or two Health District Hospitals in Obala and Mbalmayo were included in a 6-month prospective cohort analysis or cross-sectional survey, respectively. Seroprevalence and associated factors were determined, and Kaplan-Meier curves and Cox proportional hazards models were used to assess antibody persistence or positive seroconversion over time., Results: From August 2020 to March 2021, 426 HWs (median age: 31 years, interquartile range: 27-37 years; 66.4% female) were enrolled. The overall seroprevalence of anti-SARS-CoV-2 antibodies was 54.0% (95% confidence interval [CI]: 49.1-58.8) and was significantly different between study sites (p = 0.04). Of the 216 HWs included in the 6-month cohort, 109 (50.5%) HWs were seropositive at inclusion; the probability of persistent antibodies or of becoming seropositive was 93.8% (95% CI: 84.2-100) and 78.9% (95% CI: 61.7-88.4), respectively. Seroconversion was associated with study site and occupation but not with infection prevention and control (IPC) practices., Conclusions: We observed high seroprevalence of SARS-CoV-2 antibody and seroconversion among HWs associated with occupational risk. This suggests low compliance to the COVID-19 control measures. Continued training and implementation of IPC measures and accelerated preparedness are needed to better tackle future threats., (© 2024 The Authors. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd.)

We tested for Rift Valley fever virus (RVFV) from at least 15 species of non-human primates. RVFV IgG/IgM antibodies were detected in 3.7% (2 out of 53) of chimpanzees (Pan troglodytes) and in 1.4% (1 out of 72) of unidentified non-human primate species. This study was the first investigation of RVFV in monkeys in Cameroon., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Human immunodeficiency virus (HIV) is a major public health concern, particularly in Africa where HIV rates remain substantial. Pregnant women are at an increased risk of acquiring HIV, which has a significant impact on both maternal and child health., Aim: To review summarizes HIV seroprevalence among pregnant women in Africa. It also identifies regional and clinical characteristics that contribute to study-specific estimates variation., Methods: The study included pregnant women from any African country or region, irrespective of their symptoms, and any study design conducted in any setting. Using electronic literature searches, articles published until February 2023 were reviewed. The quality of the included studies was evaluated. The DerSimonian and Laird random-effects model was applied to determine HIV pooled seroprevalence among pregnant women in Africa. Subgroup and sensitivity analyses were conducted to identify potential sources of heterogeneity. Heterogeneity was assessed with Cochran's Q test and I 2 statistics, and publication bias was assessed with Egger's test., Results: A total of 248 studies conducted between 1984 and 2020 were included in the quantitative synthesis (meta-analysis). Out of the total studies, 146 (58.9%) had a low risk of bias and 102 (41.1%) had a moderate risk of bias. No HIV-positive pregnant women died in the included studies. The overall HIV seroprevalence in pregnant women was estimated to be 9.3% [95% confidence interval (CI): 8.3-10.3]. The subgroup analysis showed statistically significant heterogeneity across subgroups ( P < 0.001), with the highest seroprevalence observed in Southern Africa (29.4%, 95%CI: 26.5-32.4) and the lowest seroprevalence observed in Northern Africa (0.7%, 95%CI: 0.3-1.3)., Conclusion: The review found that HIV seroprevalence among pregnant women in African countries remains significant, particularly in Southern African countries. This review can inform the development of targeted public health interventions to address high HIV seroprevalence in pregnant women in African countries., Competing Interests: Conflict-of-interest statement: The authors deny any conflict of interest., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

While the SARS-CoV-2 dynamic has been described globally, there is a lack of data from Sub-Saharan Africa. We herein report the dynamics of SARS-CoV-2 lineages from March 2020 to March 2022 in Cameroon. Of the 760 whole-genome sequences successfully generated by the national genomic surveillance network, 74% were viral sub-lineages of origin and non-variants of concern, 15% Delta, 6% Omicron, 3% Alpha and 2% Beta variants. The pandemic was driven by SARS-CoV-2 lineages of origin in wave 1 (16 weeks, 2.3% CFR), the Alpha and Beta variants in wave 2 (21 weeks, 1.6% CFR), Delta variants in wave 3 (11 weeks, 2.0% CFR), and omicron variants in wave 4 (8 weeks, 0.73% CFR), with a declining trend over time (p = 0.01208). Even though SARS-CoV-2 heterogeneity did not seemingly contribute to the breadth of transmission, the viral lineages of origin and especially the Delta variants appeared as drivers of COVID-19 severity in Cameroon., (© 2023. The Author(s).)

Rift Valley fever (RVF) is a severe zoonotic mosquito-borne disease that represents an important threat to human and animal health, with major public health and socioeconomic impacts. This disease is endemic throughout many African countries and the Arabian Peninsula. This systematic review with meta-analysis was conducted to determine the RVF prevalence in humans, mosquitoes and other animal species in Africa. The review also provides contemporary data on RVF case fatality rate (CFR) in humans. In this systematic review with meta-analysis, a comprehensive literature search was conducted on the PubMed, Embase, Web of Science and Global Index Medicus databases from January 2000 to June 2022 to identify relevant studies. Pooled CFR and prevalence estimates were calculated using the random-effects model. Subgroup analysis and sensitivity analysis were performed, and the I 2 -statistic was used to investigate a potential source of heterogeneity. A total of 205 articles were included in the final analysis. The overall RVF CFR in humans was found to be 27.5% [95% CI = 8.0-52.5]. The overall pooled prevalence was 7.8% [95% CI = 6.2-9.6] in humans and 9.3% [95% CI = 8.1-10.6] in animals, respectively. The RVF prevalence in individual mosquitoes ranged from 0.0% to 25%. Subgroup analysis showed substantial heterogeneity with respect to geographical regions and human categories. The study shows that there is a correspondingly similar prevalence of RVF in human and animals; however, human CFR is much higher than the observed prevalence. The lack of a surveillance programme and the fact that this virus has subclinical circulation in animals and humans could explain these observations. The implementation of a One Health approach for RVF surveillance and control would be of great interest for human and animal health., (© 2023 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Human-animal pathogenic transmissions threaten both human and animal health, and the processes catalyzing zoonotic spillover and spillback are complex. Prior field studies offer partial insight into these processes but overlook animal ecologies and human perceptions and practices facilitating human-animal contact. Conducted in Cameroon and a European zoo, this integrative study elucidates these processes, incorporating metagenomic, historical, anthropological and great ape ecological analyses, and real-time evaluation of human-great ape contact types and frequencies. We find more enteric eukaryotic virome sharing between Cameroonian humans and great apes than in the zoo, virome convergence between Cameroonian humans and gorillas, and adenovirus and enterovirus taxa as most frequently shared between Cameroonian humans and great apes. Together with physical contact from hunting, meat handling and fecal exposure, overlapping human cultivation and gorilla pillaging in forest gardens help explain these findings. Our multidisciplinary study identifies environmental co-use as a complementary mechanism for viral sharing., (© 2023. The Author(s).)

Over a period of about 9 months, we conducted three serosurveys in the two major cities of Cameroon to determine the prevalence of SARS-COV-2 antibodies and to identify factors associated with seropositivity in each survey. We conducted three independent cross-sectional serosurveys of adult blood donors at the Central Hospital in Yaoundé (CHY), the Jamot Hospital in Yaoundé (JHY) and at the Laquintinie Hospital in Douala (LHD) who consented in writing to participate. Before blood sampling, a short questionnaire was administered to participants to collect their sociodemographic and clinical characteristics. We included a total of 743, 1202, and 1501 participants in the first (January 25-February 15, 2021), second (May 03-28, 2021), and third (November 29-December 31, 2021) surveys, respectively. The adjusted seroprevalence increased from 66.3% (95% CrI 61.1-71.3) in the first survey to 87.2% (95% CrI 84.0-90.0) in the second survey, and 98.4% (95% CrI 96.8-99.7) in the third survey. In the first survey, study site, participant occupation, and comorbid conditions were associated with SARS-CoV-2 seropositivity, whereas only study site remained associated in the second survey. None of the factors studied was significantly associated with seropositivity in the third survey. Together, the data suggest a rapid initial spread of SARS-CoV-2 in the study population, independent of the sociodemographic parameters assessed., (© 2023. The Author(s).)

Background and Aims: Respiratory viruses are responsible for the majority of lower respiratory tract infections (LRTIs) worldwide. However, there is a gap on the epidemiology of viral LRTIs in adults in sub-Saharan African countries. In Cameroon, like in other countries, the role of viral respiratory pathogens in the etiology of LRTIs in adults is helpful for clinical management. This study aimed to determine the viral aetiologies of LRTIs among hospitalized adults in a reference center for respiratory diseases in the town of Yaounde in Cameroon and its surroundings., Methods: A cross-sectional study was conducted from January 2017 to January 2018 at Jamot Hospital in Yaounde (Cameroon). Clinical and demographic information; BAL and sputa were collected from hospitalized patients meeting LRTI case definitions. The clinical samples were investigated for respiratory pathogens with a commercial Reverse Transcriptase Real-Time Polymerase Chain Reaction (RT-PCR) targeting 21 viruses, cultures for bacterial and fungal infections., Results: The 77 included adult patients with LRTIs had an appropriate clinical sample for microbial investigations. A viral agent was detected in 22.1% (17/77) samples. The main viruses detected included rhinovirus (10/77), coronavirus (hCoV-OC43 and hCoV-229E), and influenza A virus (3/77 each). A concomitant viral and bacterial co-infection occurred in 7.8% of patients (6/77) while viral co-infection occurred in one patient (1.3%). No Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) was detected in clinical samples. Most patients were under antimicrobials before getting diagnosed., Conclusions: Respiratory viruses account for 22.1% of LRTIs in hospitalized patients in this study. Despite prior antimicrobial therapy and delay, rhinovirus, coronavirus and influenza A virus were the most detected in patients in the pre-COVID-19 pandemic era in a single center experience from Cameroon., Competing Interests: The authors declare that there are no conflicts of interest. Supporting source/financial relationships had no involvement in study design; collection, analysis, and interpretation of data; writing of the report; and the decision to submit the report for publication., (© 2023 The Authors. Health Science Reports published by Wiley Periodicals LLC.)

Infection with viruses of animal origin pose a significant threat to human populations. Simian foamy viruses (SFVs) are frequently transmitted to humans, in which they establish a life-long infection, with the persistence of replication-competent virus. However, zoonotic SFVs do not induce severe disease nor are they transmitted between humans. Thus, SFVs represent a model of zoonotic retroviruses that lead to a chronic infection successfully controlled by the human immune system. We previously showed that infected humans develop potent neutralizing antibodies (nAbs). Within the viral envelope (Env), the surface protein (SU) carries a variable region that defines two genotypes, overlaps with the receptor binding domain (RBD), and is the exclusive target of nAbs. However, its antigenic determinants are not understood. Here, we characterized nAbs present in plasma samples from SFV-infected individuals living in Central Africa. Neutralization assays were carried out in the presence of recombinant SU that compete with SU at the surface of viral vector particles. We defined the regions targeted by the nAbs using mutant SU proteins modified at the glycosylation sites, RBD functional subregions, and genotype-specific sequences that present properties of B-cell epitopes. We observed that nAbs target conformational epitopes. We identified three major epitopic regions: the loops at the apex of the RBD, which likely mediate interactions between Env protomers to form Env trimers, a loop located in the vicinity of the heparan binding site, and a region proximal to the highly conserved glycosylation site N8. We provide information on how nAbs specific for each of the two viral genotypes target different epitopes. Two common immune escape mechanisms, sequence variation and glycan shielding, were not observed. We propose a model according to which the neutralization mechanisms rely on the nAbs to block the Env conformational change and/or interfere with binding to susceptible cells. As the SFV RBD is structurally different from known retroviral RBDs, our data provide fundamental knowledge on the structural basis for the inhibition of viruses by nAbs. Trial registration: The study was registered at www.clinicaltrials.gov: https://clinicaltrials.gov/ct2/show/NCT03225794/., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Dynesen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Rabies is a worldwide zoonotic disease mainly transmitted to humans by an infected dog bite. Despite the endemicity of rabies in dogs and few documented cases in Cameroon, there is still not enough data on frequency of rabies cases in animals. The present study aims to update data on the circulation of rabies in animals screened at the Centre Pasteur of Cameroon (CPC) between 2014 and 2021. The detection of rabies in animals was based on passive surveillance. Animal rabies cases were confirmed on brain biopsies using fluorescent antibody test and SYBR green based real-time RT-PCR for negative results confirmation. The total nucleoprotein (N) gene of animal-derived RABV isolated were amplified by hemi nested RT-PCR and subjected to phylogenetic analyses. From 2014 to 2021, a total of 92 animals including 86 dogs (93.5%), 3 cats, 2 pigs and 1 chiropteran were screened for rabies at the CPC. From the 86 dog sampled, 62.3% (54/86) were tested positive for rabies and 1 out of 3 cat samples was also tested positive. The PEP demand was very high (59,371) during the study period. Phylogenetic analyses assigned all 15 studied isolates successfully sequenced to the Africa-1a lineage belonging to the Cosmopolitan clade. The study highlights the frequent circulation of rabies in Cameroon and the role of dogs and cat as main reservoir and vector of rabies., (Copyright © 2023. Published by Elsevier Ltd.)

Background: Central Africa is one of the largest areas of high endemicity for human T-cell leukemia virus-1 (HTLV-1). However, no preventive measures are yet implemented to reduce its transmission, which can be sexual, from mother-to-child, or through contaminated blood products. Rare zoonotic transmissions from nonhuman primates (NHPs) have also been reported in this region. Here we investigated the HTLV-1 prevalence and associated risk factors in a rural population in Cameroon., Methods: From 2019 to 2021, we performed a cross-sectional survey in the eastern region of Cameroon. HTLV-1 infection was first screened by ELISA, then tested by western blot and envelope gene targeted polymerase chain reaction. Risk factors associated with HTLV-1 infection were identified by logistic regression in univariable and multivariable analyses., Results: Among 3400 participants, HTLV-1 prevalence was 1.1% (95% confidence interval [CI], .7-1.5). Factors independently associated with HTLV-1 infection were Pygmy ethnicity (adjusted odd ratio [aOR], 2.9; 95% CI, 1.3-6.2), history of surgery (aOR, 6.3; 95% CI, 2.2-17.8), and NHP bite (aOR, 6.6; 95% CI, 2.2-19.8)., Conclusions: These results suggest both iatrogenic and zoonotic transmission of HTLV-1 in Cameroon. Further studies are needed to assess the risk of nosocomial transmission of HTLV-1, to guide public health authorities in implementing preventive measures to control HTLV-1 transmission., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

Controlling the COVID-19 outbreak remains a challenge for Cameroon, as it is for many other countries worldwide. The number of confirmed cases reported by health authorities in Cameroon is based on observational data, which is not nationally representative. The actual extent of the outbreak from the time when the first case was reported in the country to now remains unclear. This study aimed to estimate and model the actual trend in the number of COVID -19 new infections in Cameroon from March 05, 2020 to May 31, 2021 based on an observed disaggregated dataset. We used a large disaggregated dataset, and multilevel regression and poststratification model was applied prospectively for COVID-19 cases trend estimation in Cameroon from March 05, 2020 to May 31, 2021. Subsequently, seasonal autoregressive integrated moving average (SARIMA) modeling was used for forecasting purposes. Based on the prospective MRP modeling findings, a total of about 7450935 (30%) of COVID-19 cases was estimated from March 05, 2020 to May 31, 2021 in Cameroon. Generally, the reported number of COVID-19 infection cases in Cameroon during this period underestimated the estimated actual number by about 94 times. The forecasting indicated a succession of two waves of the outbreak in the next two years following May 31, 2021. If no action is taken, there could be many waves of the outbreak in the future. To avoid such situations which could be a threat to global health, public health authorities should effectively monitor compliance with preventive measures in the population and implement strategies to increase vaccination coverage in the population., Competing Interests: The authors declare that they have no known competing or conflicting financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Background: Acute lower respiratory tract infections (ALRIs) are one one of the leading causes of morbidity and mortality among people of all ages worldwide, particularly in low- and middle-income countries (LMICs). The purpose of this study was to determine epidemiological characteristics of respiratory viruses in acute respiratory infection (ARI) patients during the COVID-19 pandemic in Yaoundé, Cameroon., Methods: Patients were monitored for respiratory symptoms as part of the surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other respiratory viral infections. Patients of all ages with respiratory symptoms less than 5 days were considered. Sociodemographic and clinical data as well as nasopharyngeal samples was collected from patients. Nasopharyngeal samples were tested for SARS-CoV-2, influenza, and respiratory syncytial virus (RSV) using real-time reverse-transcription polymerase chain reaction methods. Virus distribution and demographic data were analyzed with R version 2.15.1., Results: From July 2020 to October 2021, 1120 patients were included. The overall viral detection rate was 32.5%, including 9.5% for RSV, 12.6% for influenza virus and 12.8% for SARS-CoV-2. Co-infections were detected in 6.9% of positive cases. While RSV and influenza virus showed seasonal trends, SARS-CoV-2 was detected throughout the study period., Conclusion: We found that during COVID-19 pandemic, respiratory viruses play an important role in etiology of influenza-like illness in Cameroon, and this observation was true for patients of all ages., (© 2023 The Authors. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd.)

Despite the enzootic cycle of rabies in dog populations, laboratory confirmation of human rabies has been hardly reported in Cameroon. This study aimed to determine the rate of molecular detection and phylogenetic relatedness of Rabies Virus (RABV) isolates from suspected human rabies cases in Cameroon. From 2014 to 2018, 21 suspected human rabies cases were tested for RABV genomic RNA. Full-length sequence of the nucleoprotein (N) coding gene of RABV isolates detected were generated and subjected to phylogenetic analyses. As results, skin biopsies and/or saliva samples from 10 of the 21 suspected human rabies cases were positive for genomic RABV RNA. Four new N gene sequences were generated from confirmed cases. The studied RABV isolates fell into the Cosmopolitan clades, sub-clades Africa-1a and 1b. This study showed a low rate of molecular detection of RABV in suspected human rabies cases; thus, underscoring the interest of systematic laboratory confirmation., Competing Interests: Declaration of Competing Interest None., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The geographic and evolutionary origins of the SARS-CoV-2 Omicron variant (BA.1), which was first detected mid-November 2021 in Southern Africa, remain unknown. We tested 13,097 COVID-19 patients sampled between mid-2021 to early 2022 from 22 African countries for BA.1 by real-time RT-PCR. By November-December 2021, BA.1 had replaced the Delta variant in all African sub-regions following a South-North gradient, with a peak Rt of 4.1. Polymerase chain reaction and near-full genome sequencing data revealed genetically diverse Omicron ancestors already existed across Africa by August 2021. Mutations, altering viral tropism, replication and immune escape, gradually accumulated in the spike gene. Omicron ancestors were therefore present in several African countries months before Omicron dominated transmission. These data also indicate that travel bans are ineffective in the face of undetected and widespread infection.

The outbreak of coronavirus infectious disease-2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has rapidly spread throughout the world. Several studies have shown that detecting SARS-CoV-2 in untreated wastewater can be a useful tool to identify new outbreaks, establish outbreak trends, and assess the prevalence of infections. On 06 May 2021, over a year into the pandemic, we conducted a scoping review aiming to summarize research data on SARS-CoV-2 in sewage. Papers dealing with raw sewage collected at wastewater treatment plants, sewer networks, septic tanks, and sludge treatment facilities were included in this review. We also reviewed studies on sewage collected in community settings such as private or municipal hospitals, healthcare facilities, nursing homes, dormitories, campuses, airports, aircraft, and cruise ships. The literature search was conducted using the electronic databases PubMed, EMBASE, and Web Science Core Collection. This comprehensive research yielded 1090 results, 66 of which met the inclusion criteria and are discussed in this review. Studies from 26 countries worldwide have investigated the occurrence of SARS-CoV-2 in sewage of different origin. The percentage of positive samples in sewage ranged from 11.6 to 100%, with viral concentrations ranging from ˂LOD to 4.6 × 10 8 genome copies/L. This review outlines the evidence currently available on wastewater surveillance: (i) as an early warning system capable of predicting COVID-19 outbreaks days or weeks before clinical cases; (ii) as a tool capable of establishing trends in current outbreaks; (iii) estimating the prevalence of infections; and (iv) studying SARS-CoV-2 genetic diversity. In conclusion, as a cost-effective, rapid, and reliable source of information on the spread of SARS-CoV-2 and its variants in the population, wastewater surveillance can enhance genomic and epidemiological surveillance with independent and complementary data to inform public health decision-making during the ongoing pandemic., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)