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Introduction: This study compares the detection of 14 common respiratory viruses by two different real-time reverse transcription polymerase chain reaction (rRT-PCR) methods: in house singleplex tests developed by the Centers for Disease Control and Prevention and the commercially available Fast Track Diagnostic (FTD®) Respiratory Pathogens 33 multiplex test. Methods: A total of 217 nasopharyngeal swabs were analyzed using CDC singleplex rRT-PCR and FTD® Respiratory Pathogens 33 multiplex assays, for the detection of 14 respiratory viruses. Results: The results showed that 179/217 (82.5%) samples were positive with the singleplex method and 183/217 (84.3%) with the FTD® Respiratory Pathogens 33 multiplex test. Excellent or satisfactory agreement was obtained for all viruses (k > 0.6) except Parainfluenzavirus 4 (k = 0.24) and influenza B (k = 0.51). Conclusion: Although the multiplex FTD kits were more expensive than the singleplex assay, the FTD kits yielded rapid results in a shorter timeframe, increasing efficiency of diagnosis. [ABSTRACT FROM AUTHOR]

• >97% of those with chronic hepatitis C virus have viraemia >1,318 IU/ml. • Low-level viraemia among 66,640 individuals did not vary significantly by genotype. • The sensitivity of HCV diagnostic tests was maintained even when increasing the detection limit by 100×. Affordable point-of-care tests for hepatitis C (HCV) viraemia are needed to improve access to treatment in low- and middle-income countries. Our aims were to determine the target limit of detection (LOD) necessary to diagnose the majority of people with HCV eligible for treatment, and identify characteristics associated with low-level viraemia (LLV) (defined as the lowest 3% of the distribution of HCV RNA) to understand those at risk of being misdiagnosed. We established a multi-country cross-sectional dataset of first available quantitative HCV RNA measurements linked to demographic and clinical data. We excluded individuals on HCV treatment. We analysed the distribution of HCV RNA and determined critical thresholds for detection of HCV viraemia. We then performed logistic regression to evaluate factors associated with LLV, and derived relative sensitivities for significant covariates. The dataset included 66,640 individuals with HCV viraemia from across the world. The LOD for the 95th and 99th percentiles were 3,311 IU/ml and 214 IU/ml. The LOD for the 97th percentile was 1,318 IU/ml (95% CI 1,298.4–1,322.3). Factors associated with LLV, defined as HCV RNA <1,318 IU/ml, were younger age 18–30 vs. 51–64 years (odds ratios [OR] 2.56; 95% CI 2.19–2.99), female vs. male sex (OR 1.32; 95% CI 1.18–1.49), and advanced fibrosis stage F4 vs. F0-1 (OR 1.44; 95% CI 1.21–1.69). Only the younger age group had a decreased relative sensitivity below 95%, at 93.3%. In this global dataset, a test with an LOD of 1,318 IU/ml would identify 97% of viraemic HCV infections among almost all populations. This LOD will help guide manufacturers in the development of affordable point-of-care diagnostics to expand HCV testing and linkage to care in low- and middle-income countries. We created and analysed a dataset from 12 countries with 66,640 participants with chronic hepatitis C virus infection. We determined that about 97% of those with viraemic infection had 1,300 IU/ml or more of circulating virus at the time of diagnosis. While current diagnostic tests can detect as little as 12 IU/ml of virus, our findings suggest that increasing the level of detection closer to 1,300 IU/ml would maintain good test accuracy and will likely enable development of more affordable portable tests for use in low- and middle-income countries. [ABSTRACT FROM AUTHOR]

Objectives To determine the seroprevalence of hepatitis E virus (HEV) infection in patients with chronic hepatitis and/or hepatocellular carcinoma (HCC) and to assess its potential consequences for disease progression. Methods We conducted a prospective case-control study on patients with HCC hepatitis B or C related and non-HCC patients including patients with CLD and patients without clinical evidence of liver disease. Anti-HEV IgG and IgM were tested by ELISA using commercially available kits. Liver damage was assessed by alanine aminotransferase, aspartate aminotransferase, platelets and prothrombin measurements. Results We observed a significant anti-HEV IgG carriage in HCC patients compared to non-HCC subjects with CLD (41.8% vs 12.6%; P = 9.1 E-6; OR = 4.8, 95%CI: 2.3-10.6). HCC patients with HEV infection display more profound alterations of circulating liver enzymes, platelets count and prothrombin time than HCC patients without sero-reactivity to HEV. Conclusion Overall, this study indicates a high prevalence of HEV infection in Cameroonian patients with CLD and HCC. These data suggest either that patients with liver tumors are more susceptible to hepeviral infection or that, in a tropical context, HEV might promote the progression of liver diseases towards tumor. [ABSTRACT FROM AUTHOR]

• Twenty one specimens submitted for human rabies diagnostic in Cameroon from 2014 to 2018. • Low rate of molecular detection of rabies virus in suspected human rabies cases. • Four new N gene sequences obtained from confirmed human rabies cases in Cameroon. • Close identities between rabies viruses from Cameroon and Central African Republic. 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. [ABSTRACT FROM AUTHOR]

Hepatitis B surface antigen (HBsAg) is a key marker for screening and laboratory diagnosis of HBV infection. Rapid diagnostic tests (RDTs) represent promising alternatives to immunoassay-based methods because they are simple, fast and cheap. These tests, therefore, represent a powerful tool for large-scale screening and diagnosis of HBV infection in the clinical setting. Performance of 6 RDTs have been assessed in a large series of serum or plasma samples (n = 501) collected in France and in Cameroon. Specificity varied from 98.0% to 99.5%, while clinical sensitivity, compared to immunoassays as the reference, was excellent for all six RDTs (98.3%–99.3%). The VIKIA HBsAg and First Responseࣨ HBsAg Card Test reached sensitivity ≥99%. False-negative results were rare and mostly encompassed inactive HBsAg carriers or patients treated with nucleoside/nucleotide analogues. A number of RDTs may widely use to increase access to testing to all levels of the health care system. [ABSTRACT FROM AUTHOR]

Background: Scaling-up the access to hepatitis C virus (HCV) diagnostics for people who use injecting drugs (PWID) is essential to reduce the HCV incidence in low and middle-income countries.Methods: A decision tree model was developed to compare the cost-effectiveness of 12 strategies for diagnosing HCV in Senegal with a health sector perspective. Strategies included HCV-Ab screening and confirmation of viraemia (based on HCV-RNA or HCV core antigen detection) or only the latter step. Laboratory assays and decentralized tools (point-of-care (POC) tests and dried blood spot (DBS) samples) were included. The base-case assumed a 38.9% seroprevalence, as reported in the PWID population of Dakar.Results: Compared to the cheapest strategy (POC HCV-Ab followed by POC HCV-RNA (S5)), one strategy remained un-dominated in the base-case: POC HCV-Ab followed by venepuncture-based laboratory HCV-RNA (S3). Above a lost to follow-up testing rate of 2.3%, combining POC HCV-Ab with HCV-RNA on DBS (S4) became more cost-effective than S3. Above this threshold, a single-step POC HCV-RNA (S12) was also found un-dominated (ICER to S5=€3,297.50). S5, S12 and S4 cost €14.21, €17.03 and €36.55/screened individual. Incremental cost-effectiveness ratios (€/additional true positive case) were 2,164.82 (S12 versus S5) and 3,297.50 (S4 versus S12). Whenever HCV seroprevalence reached 55.5%, S12 became more cost-effective than S5. Moreover, S4 required a budget 2 to 2.5 times higher than S5 or S12 for diagnosing 90% of HCV-infected PWID in Dakar.Conclusion: A two-step POC-based strategy (S5) would be the most cost-effective option among those proposed in this study for diagnosing HCV in PWID in Senegal. This study illustrates how the lack of secure financing and of data on PWID in LMICs, render difficult to identify the most sustainable strategy in those countries, as well as its implementation. [ABSTRACT FROM AUTHOR]

Background: Human respiratory syncytial virus (HRSV) is the main viral cause of severe lower respiratory tract disease in infants and young children. The aim of this study was to describe for the first time the genetic variability of HRSV in Cameroonian patients living in Yaounde for three consecutive epidemic seasons. Methods: HRSV-positive nasopharyngeal samples detected in children less than 15 years in Yaounde were collected from September 2011 to December 2013. Semi-nested RT-PCR, sequencing, and phylogenetic analyses of the second hypervariable region of the G gene were performed. Results: A total of 57 HRSV-positive samples were collected during the study period. Among these, 46 (80.7%) could be amplified in the G gene. HRSV group A (HRSV-A) and group B (HRSV-B) co-circulated in this population at 17.4 and 82.6%, respectively. HRSV-A strains clustered in the NA-1 genotype while HRSV-B strains clustered in the BA-9 genotype. HRSV-A strains accounted for 33.3% (2/6), 4.3% (1/23), and 29.4% (5/17) of the viruses isolated in 2011, 2012, and 2013, respectively. Conclusions: This study reports molecular epidemiology data of HRSV in Cameroon for the first time. Additional studies are required to clarify evolutionary patterns of HRSV throughout sub-Saharan Africa to support antiviral and vaccine development. [ABSTRACT FROM AUTHOR]

Abstract: Background: Fourth generation assays for HIV diagnosis are progressively being introduced into routine services, due to their improvement of diagnosis. In spite of this, HIV diagnosis remains a challenge in sub-Saharan Africa, due to false positive reactivity. There is a continuous need for field evaluations and routine validations of fourth generation HIV tests in African populations. Objectives: Evaluate the performances of the ARCHITECT HIV Ag/Ab kit (Abbott) in a population living in an African setting-Cameroon compared to a population living in a European setting-France. Study design: 645 HIV samples from both France and Cameroon were evaluated. The positive panel (378 samples) included a diverse series of HIV-1 variants (groups M, N, O, and P) as well as HIV-2 samples. Results were compared to original diagnosis done with other 4th generation assays (AxSYM HIV Ag/Ab (Abbott) and Vidas HIV DUO QUICK) (bioMérieux). Results: Sensitivity of the ARCHITECT was 100% in both sites. It diagnosed all variants of the panel with different reactivity profiles following strain diversity. A wider range of reactivity was observed for group O. Specificity was slightly lower (97.6%) in Cameroon than in France (98.6%), probably due to a higher rate of false positive reactivity. ARCHITECT HIV Ag/Ab assay had high performances in clinical sensitivity and specificity and is adapted to the wide genetic diversity of viruses circulating in West Central Africa. Conclusion: Our results further highlight the need to evaluate HIV diagnostic tests before introduction into routine diagnostic services both in the North and in the South. [Copyright &y& Elsevier]

An abstract of the article "Genetic variability of Hepatitis C Virus in Moroccan population," by Ikram Brahim, Abdelah Akil, El Mostafa Mtairag, Abdelouhad El Malki, Richard Njouom, Pascal Pineau, Sayeh Ezzikouri, Soumaya Benjelloun, Salwa Nadir, and Rhimou Alaoui is presented.

This study presents a retrospective assessment of the diagnostic performance of the newly developed hepatitis B core-related antigen rapid diagnostic test (HBcrAg-RDT) in detecting plasma samples with elevated hepatitis B virus (HBV) DNA levels (≥200,000 IU/ml) in Yaoundé, Cameroon. Samples were collected consecutively from treatment-naïve adults living with HBV between January 1, 2021, and June 30, 2023. Analyzing 146 samples from participants with a median age of 36 years, the HBcrAg-RDT exhibited a sensitivity of 97.5% (95% CI: 86.8-99.9) and a specificity of 77.4% (68.2-84.9) when compared to real-time PCR as the reference standard. These findings suggest that HBcrAg-RDT holds promise as a valuable point-of-care tool for diagnosing high HBV DNA levels, particularly in resource-limited settings. Further research will refine its practicality and effectiveness., Competing Interests: Declaration of competing interest NY, AK, and KA are employees of Fujirebio Inc. YT received research grants from Gilead Sciences, Sysmex Corp, GlaxoSmithKline PLC, Fujirebio Inc, and Janssen Parmaceutical K.K. YS received research grants from Gilead Sciences and research materials from Abbott and Fujirebio Inc. The other authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Little is known about the evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunity in African communities., Aim: We evaluated changes in anti-SARS-CoV-2 antibodies, mortality and vaccination status in Cameroon between August 2021 and September 2022 to begin describing the evolution of the pandemic in Africa., Setting: The study was conducted across Cameroon's 10 regional capitals, between 2021 and 2022 as the country hosted a mass gathering., Methods: We conducted a cross-sectional population-based survey in 2022, including SARS-CoV-2 seroprevalence testing and retrospective mortality estimation using two-stage cluster sampling. We estimated and compared seroprevalence and crude mortality rates (CMR) to a survey conducted in 2021 using the same methodology., Results: We performed serologic testing on 8400 individuals and collected mortality data from 22 314 individuals. Approximately 5% in each survey reported SARS-CoV-2-vaccination. Rapid diagnostic test-based seroprevalence increased from 11.2% (95% confidence interval [CI]: 10-12.5) to 59.8% (95% CI: 58.3-61.2) between 2021 and 2022, despite no increase in the proportion vaccinated. The CMR decreased from 0.17 to 0.06 deaths per 10 000 persons per day between 2021 and 2022. In 2022, no deaths were reportedly attributable to COVID-19 as compared to 17 deaths in 2021., Conclusion: Over a 12-month period encompassing two waves of omicron variant SARS-CoV-2 and a mass gathering, SARS-CoV-2 seropositivity in Cameroon approached 60%, and deaths declined despite low vaccination coverage., Contribution: This study challenges the assumption that high immunisation coverage is the sole determinant of epidemic control in the African context and encourages policymakers to increasingly rely on local research when designing response strategies for more effective outbreak management., Competing Interests: The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article., (© 2024. The Authors.)

Rabies is a viral zoonosis that causes an estimated 60,000 human deaths each year, mainly in Africa and Asia. The etiological agent of rabies, the Rabies Lyssavirus or Rabies Virus (RABV) has been characterized in dog populations in Cameroon, in previous studies. However, the dynamics of RABV maintenance and propagation in dogs are still to be documented in Cameroon. This study thus, aimed at investigating the spatial and temporal dynamics of RABV variants in Cameroon. Long genomic sequences of about 4893 nucleotides, encompassing the N, P, M and G genes as well as part of the G-L intergenic region (Ψ), were determined from 56 RABV strains recovered from dog populations in Cameroon from 2010 to 2021. Temporal and spatial dynamics of RABV circulation in Cameroon were investigated by Bayesian analyses with the BEAST 1.10.4 package from extended RABV genomic sequences data combined with their collection dates and the geographical coordinates of their sampling areas. This revealed a genetic evolution rate of 3.14 × 10 -4 substitutions/site/year among Africa-1a and Africa-2 clades of RABV from Cameroon. The most recent common ancestor (MRCA) of the studied strains of the Africa-1a lineage was estimated to have emerged between 1880 and 1906 (95 % HPD; mean 1894), while that of the strains of the Africa-2 clade had a slightly later estimated origin between 1907 and 1928 (95 % HPD, mean 1918). Overall, phylogeographic analyses suggested RABV spread in Cameroon between sub-national regions. Our data provides substantial support to previous findings from similar epidemiological settings, indicating human mediated movements of infected dogs between distant cities may be a key factor in the maintenance of the enzootic cycle of rabies among dogs in Cameroon., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024. Published by Elsevier B.V.)

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.

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.)

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.)

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: 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.)

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.)

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.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century.

During the COVID 19 pandemic, round-the-clock demand for COVID -19 laboratory tests exceeded capacity, placing a significant burden on laboratory staff and infrastructure. The use of laboratory information management systems (LIMS) to streamline all phases of laboratory testing (preanalytical, analytical, and postanalytical) has become inevitable. The objective of this study is to describe the architecture, implementation, and requirements of PlaCARD, a software platform for managing patient registration, medical specimens, and diagnostic data flow, as well as reporting and authentication of diagnostic results during the 2019 coronavirus pandemic (COVID -19) in Cameroon. Building on its experience with biosurveillance, CPC developed an open-source, real-time digital health platform with web and mobile applications called PlaCARD to improve the efficiency and timing of disease-related interventions. PlaCARD was quickly adapted to the decentralization strategy of the COVID 19 testing in Cameroon and, after specific user training, was deployed in all COVID 19 diagnostic laboratories and the regional emergency operations center. Overall, 71% of samples tested for COVID 19 by molecular diagnostics in Cameroon from 05 March 2020 to 31 October 2021 were entered into PlaCARD. The median turnaround time for providing results was 2 days [0-2.3] before April 2021 and decreased to 1 day [1- 1] after the introduction of SMS result notification in PlaCARD. The integration of LIMS and workflow management into a single comprehensive software platform (PlaCARD) has strengthened COVID 19 surveillance capabilities in Cameroon. PlaCARD has demonstrated that it can be used as a LIMS for managing and securing test data during an outbreak., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Tchatchueng-Mbougua 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.)

This study aimed to assess the global prevalence of occult hepatitis B in blood donors. We searched PubMed, Web of Science, Global Index Medicus, and Excerpta Medica Database. Study selection and data extraction were performed by at least two independent investigators. Heterogeneity (I2) was assessed using the χ2 test on the Cochran Q statistic and H parameters. Sources of heterogeneity were explored by subgroup analyses. This study is registered with PROSPERO, number CRD42021252787. We included 82 studies in this meta-analysis. The overall prevalence of OBI was 6.2% (95% CI: 5.4-7.1) in HBsAg negative and anti-HBc positive blood donors. Only sporadic cases of OBI were reported in HBsAg negative and anti-HBc negative blood donors. The overall prevalence of OBI was 0.2% (95% CI: 0.1-0.4) in HBsAg negative blood donors. The prevalence of OBI was generally higher in countries with low-income economic status. The results of this study show that despite routine screening of blood donors for hepatitis B, the transmission of HBV by blood remains possible via OBI and/or a seronegative window period; hence there is a need for active surveillance and foremost easier access to molecular tests for the screening of blood donors before transfusion., Competing Interests: The authors have declared that no competing interests exist.

Background: The association between hospitalization for human respiratory syncytial virus (HRSV) bronchiolitis in early childhood and subsequent asthma is well established. The long-term prognosis for non-bronchiolitis lower respiratory tract infections (LRTI) caused by viruses different from HRSV and rhinovirus, on the other hand, has received less interest., Aim: To investigate the relationship between infant LRTI and later asthma and examine the influence of confounding factors., Methods: The PubMed and Global Index Medicus bibliographic databases were used to search for articles published up to October 2021 for this systematic review. We included cohort studies comparing the incidence of asthma between patients with and without LRTI at ≤ 2 years regardless of the virus responsible. The meta-analysis was performed using the random effects model. Sources of heterogeneity were assessed by stratified analyses., Results: This review included 15 articles (18 unique studies) that met the inclusion criteria. LRTIs at ≤ 2 years were associated with an increased risk of subsequent asthma up to 20 years [odds ratio (OR) = 5.0, 95%CI: 3.3-7.5], with doctor-diagnosed asthma (OR = 5.3, 95%CI: 3.3-8.6), current asthma (OR = 5.4, 95%CI: 2.7-10.6), and current medication for asthma (OR = 1.2, 95%CI: 0.7-3.9). Our overall estimates were not affected by publication bias ( P = 0.671), but there was significant heterogeneity [ I 2 = 58.8% (30.6-75.5)]. Compared to studies with hospitalized controls without LRTI, those with ambulatory controls had a significantly higher strength of association between LRTIs and subsequent asthma. The strength of the association between LRTIs and later asthma varied significantly by country and age at the time of the interview. The sensitivity analyses including only studies with similar proportions of confounding factors (gender, age at LRTI development, age at interview, gestational age, birth weight, weight, height, smoking exposure, crowding, family history of atopy, and family history of asthma) between cases and controls did not alter the overall estimates., Conclusion: Regardless of the causative virus and confounding factors, viral LRTIs in children < 2 years are associated with an increased risk of developing a subsequent asthma. Parents and pediatricians should be informed of this risk., Competing Interests: Conflict-of-interest statement: The authors deny any conflict of interest., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Introduction: Due to their common routes of transmission, human immunodeficiency virus (HIV) coinfection with hepatitis B virus (HBV) and/or hepatitis C virus (HCV) has become a major public health problem worldwide, particularly in Africa, where these viruses are endemic. Few systematic reviews report the epidemiological data of HBV and/or HCV coinfection with HIV in Africa, and none provided data on the case fatality rate (CFR) associated with this coinfection. This study was conducted to investigate the prevalence and case fatality rate of HBV and/or HCV infections among people living with human immunodeficiency virus (PLHIV) in Africa., Methods: We conducted a systematic review of published articles in PubMed, Web of Science, African Journal Online, and African Index Medicus up to January 2022. Manual searches of references from retrieved articles and grey literature were also performed. The meta-analysis was performed using a random-effects model. Sources of heterogeneity were investigated using subgroup analysis, while funnel plots and Egger tests were performed to assess publication bias., Results: Of the 4388 articles retrieved from the databases, 314 studies met all the inclusion criteria. The overall HBV case fatality rate estimate was 4.4% (95% CI; 0.7-10.3). The overall seroprevalences of HBV infection, HCV infection, and HBV/HCV coinfection in PLHIV were 10.5% [95% CI = 9.6-11.3], 5.4% [95% CI = 4.6-6.2], and 0.7% [95% CI = 0.3-1.0], respectively. The pooled seroprevalences of current HBsAg, current HBeAg, and acute HBV infection among PLHIV were 10.7% [95% CI = 9.8-11.6], 7.0% [95% CI = 4.7-9.7], and 3.6% [95% CI = 0.0-11.0], respectively. Based on HBV-DNA and HCV-RNA detection, the seroprevalences of HBV and HCV infection in PLHIV were 17.1% [95% CI = 11.5-23.7] and 2.5% [95% CI = 0.9-4.6], respectively. Subgroup analysis showed substantial heterogeneity., Conclusions: In Africa, the prevalence of hepatotropic viruses, particularly HBV and HCV, is high in PLHIV, which increases the case fatality rate. African public health programs should emphasize the need to apply and comply with WHO guidelines on viral hepatitis screening and treatment in HIV-coinfected patients., Review Registration: PROSPERO, CRD42021237795., Competing Interests: The authors have declared that no competing interests exist.

Background: Occult hepatitis C infection (OCI) is characterized by the presence of hepatitis C virus (HCV) RNA in the liver, peripheral blood mononuclear cells (PBMC) and/or ultracentrifuged serum in the absence of detectable HCV-RNA in serum. OCI has been described in several categories of populations including hemodialysis patients, patients with a sustained virological response, immunocompromised individuals, patients with abnormal hepatic function, and apparently healthy subjects., Aim: To highlight the global prevalence of OCI., Methods: We performed a systematic and comprehensive literature search in the following 4 electronic databases PubMed, EMBASE, Global Index Medicus, and Web of Science up to 6th May 2021 to retrieve relevant studies published in the field. Included studies were unrestricted population categories with known RNA status in serum, PBMC, liver tissue and/or ultracentrifuged serum. Data were extracted independently by each author and the Hoy et al tool was used to assess the quality of the included studies. We used the random-effect meta-analysis model to estimate the proportions of OCI and their 95% confidence intervals (95%CI). The Cochran's Q -test and the I 2 test statistics were used to assess heterogeneity between studies. Funnel plot and Egger test were used to examine publication bias. R software version 4.1.0 was used for all analyses., Results: The electronic search resulted in 3950 articles. We obtained 102 prevalence data from 85 included studies. The pooled prevalence of seronegative OCI was estimated to be 9.61% (95%CI: 6.84-12.73) with substantial heterogeneity [ I ² = 94.7% (95%CI: 93.8%-95.4%), P < 0.0001]. Seropositive OCI prevalence was estimated to be 13.39% (95%CI: 7.85-19.99) with substantial heterogeneity [ I 2 = 93.0% (90.8%-94.7%)]. Higher seronegative OCI prevalence was found in Southern Europe and Northern Africa, and in patients with abnormal liver function, hematological disorders, and kidney diseases. Higher seropositive OCI prevalence was found in Southern Europe, Northern America, and Northern Africa., Conclusion: In conclusion, in the present study, it appears that the burden of OCI is high and variable across the different regions and population categories. Further studies on OCI are needed to assess the transmissibility, clinical significance, long-term outcome, and need for treatment., Competing Interests: Conflict-of-interest statement: The authors deny any conflict of interest., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: In sub-Saharan Africa, administration of hepatitis B virus (HBV) birth-dose vaccines remains suboptimal. Evidence is scarce on whether African countries should focus on increasing vaccine coverage or developing strategies incorporating additional measures, such as peripartum antiviral prophylaxis to pregnant women at high risk. To better inform decision makers, we estimated the residual risk of mother-to-child transmission despite HBV birth-dose vaccine in Cameroon., Methods: We did a single-centre, longitudinal observational study. Pregnant women were systematically screened for HBV surface antigen (HBsAg) at Tokombéré District Hospital (Tokombéré district, Cameroon). Children born to HBsAg-positive mothers in 2009-16 who received the HBV birth-dose vaccine and three subsequent doses of pentavalent vaccine at 6, 10, and 14 weeks were followed up prospectively in 2015-17. In children, capillary blood was obtained for HBsAg rapid test and dried blood spots to quantify HBV DNA concentrations. Venous blood was also collected from HBsAg-positive children. Mother-to-child transmission was confirmed by whole-genome sequencing., Findings: Between Jan 31, 2009, and Dec 31, 2016, 22 243 (66·8%) of 33 309 pregnant women accepted antenatal HBV screening, of whom 3901 (17·5%) were HBsAg positive. 2004 (51·4%) of 3901 children who were born to HBsAg-positive mothers received the HBV birth-dose vaccine, of whom 1800 (89·8%) also completed the three-dose pentavalent vaccine. In total, the current analysis included 607 children who had a follow-up serosurvey. The prevalence of HBsAg was 5·6% in children who received the birth-dose vaccine in less than 24 h, 7·0% in those who received it 24-47 h after birth, and 16·7% in those who received it 48-96 h after birth (p trend =0·083). 35 (89·7%) of 39 infected children were born to mothers positive for HBV e antigen with high HBV DNA of 5·3 log 10 IU/mL or more. Whole-genome sequencing of HBV in infected mother-child pairs confirmed high identity proportions of 99·97-100%., Interpretation: We documented a substantial risk of mother-to-child transmission despite timely administration of the HBV birth-dose vaccine within 24 h after birth. To reach WHO's elimination targets, peripartum antiviral prophylaxis might be required in parts of Africa, in addition to increasing coverage of the HBV birth-dose vaccine., Funding: Agence nationale de recherches sur le sida et les hépatites virales (ANRS)., Competing Interests: Declaration of interests YS has received a research grant from Gilead. All other authors declare no competing interests., (Copyright © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: The prevalence of hepatitis B virus (HBV) infection varies geographically around the world. Yet, its underlying mechanisms are unknown. Using a nationally representative population-based sample from all 58 administrative divisions in Cameroon, we examined the association between median maternal age at first childbirth in a preceding generation, a proxy for the frequency of mother-to-child transmission (MTCT) of HBV in a region, and the risk of chronic HBV infection, defined as positive surface antigen (HBsAg), in the index generation., Methods: We estimated a division-specific median maternal age at first childbirth using Demographic Health Surveys (DHSs) conducted in 1991, 1998, 2004, and 2011. We tested HBsAg in 2011 DHS participants. We used maps to display spatial variation., Results: In 14 150 participants (median age, 27 years; 51% females), the overall weighted prevalence of HBsAg was 11.9% (95% confidence interval [CI], 11.0 to 12.8), with a wide geographical variation across the divisions (range, 6.3%-23.7%). After adjusting for confounders and spatial dependency, lower maternal age at first childbirth was significantly associated with positive HBsAg at the division level (β, 1.89; 95% CI, 1.26 to 2.52) and at the individual level (odds ratio, 1.20; 95% CI, 1.04 to 1.39). A similar ecological correlation was observed across other African countries., Conclusions: The significant association between the maternal age at first childbirth and HBsAg positivity suggests a crucial role of MTCT in maintaining high HBV endemicity in some areas in Cameroon. This underlines an urgent need to effectively prevent MTCT in sub-Saharan Africa., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objective: A single study conducted about three decades ago on hepatitis D virus (HDV) infection among Baka pygmies in Cameroon reported a very high anti-HDV antibodies prevalence of 46%, but HDV genetic diversity has not been studied in this population. The genetic diversity of strains from endemic ancient populations may help to understand the origin and evolutionary history of viruses. This study aimed to investigate the HDV seroprevalence and the genetic diversity in three remote Cameroonian Pygmies with chronic HBV infection., Results: An unusually high 69% (36/52) level of HDV infection was found among HBsAg-positive pygmies in Cameroon. HDV RNA was detected and sequenced in 38.8% (14/36). The phylogenetic analysis revealed that 9/14 strains (64.3%) were identified and classified as genotype 1 (HDV-1) and 5/14 (35.6%) as genotype 7 (HDV-7), respectively with a bootstrap value of 100%. The further analysis showed the co-circulation of highly diverse HDV genotypes HDV-1 and HDV-7 in this population. These results highlight the endemicity of HDV infection in Central Africa. The highly diverse HDV-1 and HDV-7 in pygmies suggest an African origin of HDV. However, further studies are needed with larger sample size., (© 2022. The Author(s).)

A substantial amount of epidemiological data has been reported on Enterovirus D68 (EV-D68) infections after the 2014 outbreak. Our goal was to map the case fatality rate (CFR) and prevalence of current and past EV-D68 infections. We conducted a systematic review (PROSPERO, CRD42021229255) with published articles on EV-68 infections in PubMed, Embase, Web of Science and Global Index Medicus up to January 2021. We determined prevalences using a model random effect. Of the 4,329 articles retrieved from the databases, 89 studies that met the inclusion criteria were from 39 different countries with apparently healthy individuals and patients with acute respiratory infections, acute flaccid myelitis and asthma-related diseases. The CFR estimate revealed occasional deaths (7/1353) related to EV-D68 infections in patients with severe acute respiratory infections. Analyses showed that the combined prevalence of current and past EV-D68 infections was 4% (95% CI = 3.1-5.0) and 66.3% (95% CI = 40.0-88.2), respectively. The highest prevalences were in hospital outbreaks, developed countries, children under 5, after 2014, and in patients with acute flaccid myelitis and asthma-related diseases. The present study shows sporadic deaths linked to severe respiratory EV-D68 infections. The study also highlights a low prevalence of current EV-D68 infections as opposed to the existence of EV-D68 antibodies in almost all participants of the included studies. These findings therefore highlight the need to implement and/or strengthen continuous surveillance of EV-D68 infections in hospitals and in the community for the anticipation of the response to future epidemics., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Africa denotes unique facies for hepatocellular carcinoma (HCC) characterized by a conjunction of low sensitization, restricted access to diagnosis and treatment and associated with the highest incidence and mortality in the world. We investigated whether hepatitis B (HBV), C (HCV) and D (VHD) viruses were etiological agents of HCC in Africa., Methods: Relevant articles were searched in PubMed, Web of Science, African Index Medicus, and African Journal Online databases, as well as manual searches in relevant reviews and included articles. Analytical studies from Africa evaluating the association between HCC development and HBV, HCV, and HDV were included. Relevant studies were selected, data extracted, and the risk of bias assessed independently by at least 2 investigators. The association was estimated using odds ratios (OR) and their 95% confidence interval (95% CI) determined by a random-effects model. Sources of heterogeneity were determined by subgroup analyses., Results: A total of 36 case-control studies were included. With controls having non-hepatic disease, the overall results suggested a significantly increased risk of HCC in patients with HBV (HBeAg (OR = 19.9; 95% CI = [3.7-105.2]), HBsAg (OR = 9.9; 95%) CI = [6.2-15.6]) and DNA (OR = 8.9; 95% CI = [5.9-13.4]); HCV (Anti-HCV (OR = 9.4; 95% CI = [6.3-14.0]) and RNA (OR = 16.5; 95% CI = [7.8-34.6]); HDV (Anti-VHD, (OR = 25.8; 95% CI = [5.9-112.2]); and HBV/HCV coinfections (HBV DNA/HCV RNA (OR = 22.5; 95% CI = [1.3-387.8]). With apparently healthy controls, the overall results suggested a significantly increased risk of HCC in patients with HBV (HBsAg, (OR = 8.9; 95% CI = [6.0-13.0]); HCV (Anti-HCV, (OR = 7.7; 95% CI = [5.6-10.6]); and HBV/HCV coinfections (HBsAg/Anti-HCV (OR = 7.8; 95% CI = [4.4-13.6]) Substantial heterogeneity and the absence of publication bias were recorded for these results., Conclusions: In Africa, HBV/HCV coinfections and HBV, HCV, and HDV infections are associated with an increased risk of developing HCC. The implementation of large-scale longitudinal and prospective studies including healthy participants to search for early biomarkers of the risk of progression to HCC is urgently needed., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Meta-analyses conducted so far on the association between diabetes mellitus (DM) and the tuberculosis (TB) development risk did not sufficiently take confounders into account in their estimates. The objective of this systematic review was to determine whether DM is associated with an increased risk of developing TB with a sensitivity analyses incorporating a wider range of confounders including age, gender, alcohol consumption, smoke exposure, and other comorbidities., Methods: Pubmed, Embase, Web of Science and Global Index Medicus were queried from inception until October 2020. Without any restriction to time of study, geographical location, and DM and TB diagnosis approaches, all observational studies that presented data for associations between DM and TB were included. Studies with no abstract or complete text, duplicates, and studies with wrong designs (review, case report, case series, comment on an article, and editorial) or populations were excluded. The odds ratios (OR) and their 95% confidence intervals were estimated by a random-effect model., Results: The electronic and manual searches yielded 12,796 articles of which 47 were used in our study (23 case control, 14 cross-sectional and 10 cohort studies) involving 503,760 cases (DM or TB patients) and 3,596,845 controls. The size of the combined effect of TB risk in the presence of DM was OR = 2.3, 95% CI = [2.0-2.7], I2 = 94.2%. This statistically significant association was maintained in cohort (OR = 2.0, CI 95% = [1.5-2.4], I2 = 94.3%), case control (OR = 2.4, CI 95% = [2.0-2.9], I2 = 93.0%) and cross-sectional studies (OR = 2.5, CI 95% = [1.8-3.5], I2 = 95.2%). The association between DM and TB was also maintained in the sensitivity analysis including only studies with similar proportions of confounders between cases and controls. The substantial heterogeneity observed was mainly explained by the differences between geographic regions., Conclusions: DM is associated with an increased risk of developing latent and active TB. To further explore the role of DM in the development of TB, more investigations of the biological mechanisms by which DM increases the risk of TB are needed., Review Registration: PROSPERO, CRD42021216815., Competing Interests: The authors have declared that no competing interests exist.

The progression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in Africa has so far been heterogeneous, and the full impact is not yet well understood. In this study, we describe the genomic epidemiology using a dataset of 8746 genomes from 33 African countries and two overseas territories. We show that the epidemics in most countries were initiated by importations predominantly from Europe, which diminished after the early introduction of international travel restrictions. As the pandemic progressed, ongoing transmission in many countries and increasing mobility led to the emergence and spread within the continent of many variants of concern and interest, such as B.1.351, B.1.525, A.23.1, and C.1.1. Although distorted by low sampling numbers and blind spots, the findings highlight that Africa must not be left behind in the global pandemic response, otherwise it could become a source for new variants.

Background: The hepatitis B virus (HBV) infection is a global public health concern that affects about 2 billion people and causes 1 million people deaths yearly. HBV is a blood-borne disease and healthcare workers (HCWs) are a high-risk group because of occupational hazard to patients' blood. Different regions of the world show a highly variable proportion of HCWs infected and/or immunized against HBV. Global data on serologic markers of HBV infection and immunization in HCWs are very important to improve strategies for HBV control., Aim: To determine the worldwide prevalence of HBV serological markers among HCWs., Methods: In this systematic review and meta-analyses, we searched PubMed and Excerpta Medica Database (Embase) to identify studies published between 1970 and 2019 on the prevalence of HBV serological markers in HCWs worldwide. We also manually searched for references of relevant articles. Four independent investigators selected studies and included those on the prevalence of each of the HBV serological markers including hepatitis B surface antigen (HBsAg), hepatitis e antigen (HBeAg), immunoglobulin M anti-HBc, and anti-HBs. Methodological quality of eligible studies was assessed and random-effect model meta-analysis resulted in the pooled prevalence of HBV serological markers HBV infection in HCWs. Heterogeneity ( I² ) was assessed using the χ² test on Cochran's Q statistic and H parameters. Heterogeneity' sources were explored through subgroup and metaregression analyses. This study is registered with PROSPERO, number CRD42019137144., Results: We reviewed 14059 references, out of which 227 studies corresponding to 448 prevalence data among HCWs (224936 HCWs recruited from 1964 to 2019 in 71 countries) were included in this meta-analysis. The pooled seroprevalences of current HBsAg, current HBeAg, and acute HBV infection among HCWs were 2.3% [95% confidence interval (CI): 1.9-2.7], 0.2% (95%CI: 0.0-1.7), and 5.3% (95%CI: 1.4-11.2), respectively. The pooled seroprevalences of total immunity against HBV and immunity acquired by natural HBV infection in HCWs were 56.6% (95%CI: 48.7-63.4) and 9.2% (95%CI: 6.8-11.8), respectively. HBV infection was more prevalent in HCWs in low-income countries, particularly in Africa. The highest immunization rates against HBV in HCWs were recorded in urban areas and in high-income countries including Europe, the Eastern Mediterranean and the Western Pacific., Conclusion: New strategies are needed to improve awareness, training, screening, vaccination, post-exposure management and treatment of HBV infection in HCWs, and particularly in low-income regions., Competing Interests: Conflict-of-interest statement: The authors deny any conflict of interest., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Acute respiratory infections (ARI) are associated with a huge morbidity and mortality worldwide. Rhinoviruses (RVs) and Enteroviruses (EVs) are recognized as leading causes of ARI., Objectives: The present study describes the molecular epidemiology of RVs and EVs in Cameroon over a 3-year surveillance period., Methods: From September 2011 to October 2014, nasopharyngeal swabs were collected from patients with influenza-like illness (ILI) and severe acute respiratory infections (SARI). Two sub-genomic regions of the EVs and RVs were targeted for molecular characterization. These included the most conserved 5'-untranslated region (5'UTR) and the viral protein 4/viral protein 2 transition region (VP4/VP2)., Results: A total of 974 samples were collected. Children ≤5 years accounted for 85.7% (835/974) of all participants. Among them, 160 (16.4%) were positive for RVs and/or EVs. RVs and/or EVs were significantly more identified in ILI compared to SARI patients (P = .015). Both viruses co-circulated all year long with a marked increase of occurrence during rainy and cold season. All RV species were found to circulate in Cameroon, with 6, 10 and 6 virus types belonging to the RV-A, RV-B and RV-C, respectively. EV species identified comprised EV-A (1 Coxsackie virus A5), EV-B (1 Coxsackie virus A9 and 2 Coxsackie virus B1) and EV-C (1 EV-C117)., Conclusions: This study indicates a strong year-round occurrence of EV and RV associated respiratory infections in Cameroon. Molecular characterization identified a wide variety of RVs and EVs in patients with ARI in Cameroon., (© 2021 The Authors. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd.)

Background: Real-time PCR is recommended to detect SARS-CoV-2 infection. However, PCR availability is restricted in most countries. Rapid diagnostic tests are considered acceptable alternatives, but data are lacking on their performance. We assessed the performance of four antibody-based rapid diagnostic tests and one antigen-based rapid diagnostic test for detecting SARS-CoV-2 infection in the community in Cameroon., Methods: In this clinical, prospective, diagnostic accuracy study, we enrolled individuals aged at least 21 years who were either symptomatic and suspected of having COVID-19 or asymptomatic and presented for screening. We tested peripheral blood for SARS-CoV-2 antibodies using the Innovita (Biological Technology; Beijing, China), Wondfo (Guangzhou Wondfo Biotech; Guangzhou, China), SD Biosensor (SD Biosensor; Gyeonggi-do, South Korea), and Runkun tests (Runkun Pharmaceutical; Hunan, China), and nasopharyngeal swabs for SARS-CoV-2 antigen using the SD Biosensor test. Antigen rapid diagnostic tests were compared with Abbott PCR testing (Abbott; Abbott Park, IL, USA), and antibody rapid diagnostic tests were compared with Biomerieux immunoassays (Biomerieux; Marcy l'Etoile, France). We retrospectively tested two diagnostic algorithms that incorporated rapid diagnostic tests for symptomatic and asymptomatic patients using simulation modelling., Findings: 1195 participants were enrolled in the study. 347 (29%) tested SARS-CoV-2 PCR-positive, 223 (19%) rapid diagnostic test antigen-positive, and 478 (40%) rapid diagnostic test antibody-positive. Antigen-based rapid diagnostic test sensitivity was 80·0% (95% CI 71·0-88·0) in the first 7 days after symptom onset, but antibody-based rapid diagnostic tests had only 26·8% sensitivity (18·3-36·8). Antibody rapid diagnostic test sensitivity increased to 76·4% (70·1-82·0) 14 days after symptom onset. Among asymptomatic participants, the sensitivity of antigen-based and antibody-based rapid diagnostic tests were 37·0% (27·0-48·0) and 50·7% (42·2-59·1), respectively. Cohen's κ showed substantial agreement between Wondfo antibody rapid diagnostic test and gold-standard ELISA (κ=0·76; sensitivity 0·98) and between Biosensor and ELISA (κ=0·60; sensitivity 0·94). Innovita (κ=0·47; sensitivity 0·93) and Runkun (κ=0·43; sensitivity 0·76) showed moderate agreement. An antigen-based retrospective algorithm applied to symptomatic patients showed 94·0% sensitivity and 91·0% specificity in the first 7 days after symptom onset. For asymptomatic participants, the algorithm showed a sensitivity of 34% (95% CI 23·0-44·0) and a specificity of 92·0% (88·0-96·0)., Interpretation: Rapid diagnostic tests had good overall sensitivity for diagnosing SARS-CoV-2 infection. Rapid diagnostic tests could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and onward viral transmission., Funding: Médecins Sans Frontières WACA and Médecins Sans Frontières OCG., Translations: For the French and Spanish translations of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests We declare no conflicting interests., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Official case counts suggest Africa has not seen the expected burden of COVID-19 as predicted by international health agencies, and the proportion of asymptomatic patients, disease severity, and mortality burden differ significantly in Africa from what has been observed elsewhere. Testing for SARS-CoV-2 was extremely limited early in the pandemic and likely led to under-reporting of cases leaving important gaps in our understanding of transmission and disease characteristics in the African context. SARS-CoV-2 antibody prevalence and serologic response data could help quantify the burden of COVID-19 disease in Africa to address this knowledge gap and guide future outbreak response, adapted to the local context. However, such data are widely lacking in Africa. We conducted a cross-sectional seroprevalence survey among 1,192 individuals seeking COVID-19 screening and testing in central Cameroon using the Innovita antibody-based rapid diagnostic. Overall immunoglobulin prevalence was 32%, IgM prevalence was 20%, and IgG prevalence was 24%. IgM positivity gradually increased, peaking around symptom day 20. IgG positivity was similar, gradually increasing over the first 10 days of symptoms, then increasing rapidly to 30 days and beyond. These findings highlight the importance of diagnostic testing and asymptomatic SARS-CoV-2 transmission in Cameroon, which likely resulted in artificially low case counts. Rapid antibody tests are a useful diagnostic modality for seroprevalence surveys and infection diagnosis starting 5-7 days after symptom onset. These results represent the first step towards better understanding the SARS-CoV-2 immunological response in African populations., Competing Interests: We declare no competing interests., (© 2021 The Authors.)

Aim: HCV diagnosis will become the bottleneck in eliminating hepatitis C. Simple, accurate and cost-effective testing strategies are urgently needed to improve hepatitis C screening and diagnosis. Materials & methods: Performance of seven rapid diagnostic tests (RDT) have been assessed in a large series (n = 498) of serum or plasma specimens collected in France and in Cameroon. Results: Specificity varied from 96.1 to 100%. The clinical sensitivity, compared with immunoassays as the reference, was high for all seven RDT (97.2-100%). The Multisure HCV antibody assay and OraQuick HCV rapid antibody test reached sensitivity ≥99%. Conclusion: A number of RDT may be suitable for WHO prequalification and may be implemented in the framework of large-scale low-cost treatment programs to achieve the WHO viral hepatitis objectives by 2030.