Investigating animal reservoirs for hepatitis E virus in Bangui, Central African Republic.

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.

Hepatitis E virus infections among patients with acute febrile jaundice in two regions of Cameroon: First molecular characterization of hepatitis E virus genotype 4.

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.

Incidence and seroprevalence of rabies virus in humans, dogs and other animal species in Africa, a systematic review and meta-analysis.

Rabies is transmitted to humans mainly by dogs but also by other animal species. Reliable data on the incidence of Rabies virus (RABV) in humans, dogs, and other animal species in Africa, could be essential in the implementation of a global strategic plan to eliminate the RABV by 2030 as adopted by the WHO, OIE, and FAO. We searched the Pubmed, Embase, Scopus, African Journal Online, and African Index Medicus databases for relevant studies that report data on the incidence of RABV in Africa up to February 17, 2020. Information on active and past RABV exposures in various categories of dogs, humans and other animal species were extracted. Incidence and seroprevalence estimates were pooled using a random-effect meta-analysis. We included 73 articles which provided 142 RABV incidence and seroprevalence records in 21 African countries. The estimated incidence of RABV in 222 humans, 15,600 dogs, and 12,865 other animal species was 83.4% (95% CI = 64.6-96.5), 44.1% (95% CI = 35.1-53.4), and 41.4% (95% CI = 29.6-53.8), respectively. The estimated seroprevalence of RABV in 420 humans, 3577 dogs, and 8,55 other animal species was 33.8% (95% CI = 21.9-46.8), 19.8% (95% CI = 13.3-27.3), and 3.6% (95% CI = 0.3-9.2), respectively. The incidence of RABV in general was higher in suspected rabid dogs, other animal species of the Orders Perissodactyla, Artiodactyla and Carnivora. The incidence of RABV was higher for humans in regions of West and East Africa, for dogs in urban areas and in regions of Central and South Africa, and for animals of the order Perissodactyla in urban areas. This meta-analysis demonstrated a high incidence of RABV in Africa. Itis necessary to improve surveillance system to provide reliable data on RABV in Africa, essential for the implementation of an effective control strategy.

Worldwide epidemiology of Crimean-Congo Hemorrhagic Fever Virus in humans, ticks and other animal species, a systematic review and meta-analysis.

There are uncertainties about the global epidemiological data of infections due to Crimean-Congo hemorrhagic fever virus (CCHFV). We estimated the global case fatality rate (CFR) of CCHFV infections and the prevalence of CCHFV in humans, ticks and other animal species. We also explored the socio-demographic and clinical factors that influence these parameters. In this systematic review with meta-analyses we searched publications from database inception to 03rd February 2020 in Pubmed, Scopus, and Global Index Medicus. Studies included in this review provided cross-sectional data on the CFR and/or prevalence of one or more targets used for the detection of CCHFV. Two independent investigators selected studies to be included. Data extraction and risk of bias assessment were conducted independently by all authors. Data collected were analysed using a random effect meta-analysis. In all, 2345 records were found and a total of 312 articles (802 prevalence and/or CFR data) that met the inclusion criteria were retained. The overall CFR was 11.7% (95% CI = 9.1-14.5), 8.0% (95% CI = 1.0-18.9), and 4.7% (95% CI = 0.0-37.6) in humans with acute, recent, and past CCHFV infections respectively. The overall CCHFV acute infections prevalence was 22.5% (95% CI = 15.7-30.1) in humans, 2.1% (95% CI = 1.3-2.9) in ticks, and 4.5% (95% CI = 1.9-7.9) in other animal species. The overall CCHFV recent infections seroprevalence was 11.6% (95% CI = 7.9-16.4) in humans and 0.4% (95% CI = 0.0-2.9) in other animal species. The overall CCHFV past infections seroprevalence was 4.3% (95% CI = 3.3-5.4) in humans and 12.0% (95% CI = 9.9-14.3) in other animal species. CFR was higher in low-income countries, countries in the WHO African, South-East Asia and Eastern Mediterranean regions, in adult and ambulatory patients. CCHFV detection rate in humans were higher in CCHFV suspected cases, healthcare workers, adult and hospitalized patients, ticks of the genus Ornithodoros and Amblyomma and in animals of the orders Perissodactyla and Bucerotiformes. This review highlights a significant disease burden due to CCHFV with a strong disparity according to country income levels, geographic regions, various human categories and tick and other animal species. Preventive measures in the light of these findings are expected.

Epidemiology of hepatitis E virus infection in animals in Africa: a systematic review and meta-analysis.

BACKGROUND: Hepatitis E virus (HEV) is a major cause of acute hepatitis in humans worldwide and have high burden in the resource-limited countries. Better knowledge of the epidemiology of hepatitis in animals in Africa can help to understand the epidemiology among humans. The objective of this study was to summarize the prevalence of HEV infection and distribution of HEV genotypes among animals in Africa. METHODS: In this systematic review and meta-analysis, we comprehensively searched PubMed, EMBASE, African Journals Online, and Africa Index Medicus from January 1st, 2000 to March 22th, 2020 without any language restriction. We considered cross-sectional studies of HEV infection in animals in Africa. Study selection, data extraction, and methodological quality of included studies were done independently by two investigators. Prevalence data were pooled using the random-effects meta-analysis. This review was registered in PROSPERO, CRD42018087684. RESULTS: Twenty-five studies (13 species and 6983 animals) were included. The prevalence (antibodies or ribonucleic acid [RNA]) of HEV infection in animals varied widely depending on biological markers of HEV infection measured: 23.4% (95% confidence interval; 12.0-37.2) for anti-HEV immunoglobulins G, 13.1% (3.1-28.3) for anti-HEV immunoglobulins M, and 1.8% (0.2-4.3) for RNA; with substantial heterogeneity. In subgroup analysis, the immunoglobulins G seroprevalence was higher among pigs 37.8% (13.9-65.4). The following HEV genotypes were reported in animals: Rat-HEV genotype 1 (rats and horses), HEV-3 (pigs), HEV-7 (dromedaries), and Bat hepeviruses (bats). CONCLUSIONS: We found a high prevalence of HEV infection in animals in Africa and HEV genotypes close to that of humans. Some animals in Africa could be the reservoir of HEV, highlighting the need of molecular epidemiological studies for investigating zoonotic transmission.

First molecular characterization of the hepatitis E virus in humans in Cameroon: Confirmation of the HEV outbreak in Touboro, North-Cameroon.

Hepatitis E virus (HEV) is a major causative agent of acute viral hepatitis in many regions of the world including Africa. In Cameroon, there is no published molecular study on HEV in humans. However, based on serological assays, the first outbreak of HEV was detected in North-Cameroon. The objective of this study was to determine the molecular characterization of HEV that circulated during this period. A retrospective study design was used to select serum samples among those collected during the outbreak period. immunoglobulin M positive samples available in sufficient volumes to amplify HEV RNA were selected. RNA was extracted and then amplified by a real-time reverse transcription polymerase chain reaction (real time RT-PCR) assay, followed by a nested reverse transcription polymerase chain reaction (nested RT-PCR) assay for sequencing and phylogenetic analysis. Overall, 24 samples were selected and HEV RNA was amplified by real-time RT-PCR in 20 samples. Amongst these, 12 samples were positive for HEV RNA by nested RT-PCR and yielded good sequencing products. Phylogenetic analysis showed that 10 samples clustered with HEV genotype 1 (subtype 1e) and two samples clustered with HEV genotype 3 (subtype 3f). This study fills the gap of knowledge on the molecular epidemiology of HEV in Cameroon and confirms the first report of the hepatitis E outbreak in North-Cameroon.

Prevalence of respiratory viruses using polymerase chain reaction in children with wheezing, a systematic review and meta-analysis.

INTRODUCTION: Wheezing is a major problem in children, and respiratory viruses are often believed to be the causative agent. While molecular detection tools enable identification of respiratory viruses in wheezing children, it remains unclear if and how these viruses are associated with wheezing. The objective of this systematic review is to clarify the prevalence of different respiratory viruses in children with wheezing. METHODS: We performed an electronic in Pubmed and Global Index Medicus on 01 July 2019 and manual search. We performed search of studies that have detected common respiratory viruses in children ≤18 years with wheezing. We included only studies using polymerase chain reaction (PCR) assays. Study data were extracted and the quality of articles assessed. We conducted sensitivity, subgroup, publication bias, and heterogeneity analyses using a random effects model. RESULTS: The systematic review included 33 studies. Rhinovirus, with a prevalence of 35.6% (95% CI 24.6-47.3, I2 98.4%), and respiratory syncytial virus, at 31.0% (95% CI 19.9-43.3, I2 96.4%), were the most common viruses detected. The prevalence of other respiratory viruses was as follows: human bocavirus 8.1% (95% CI 5.3-11.3, I2 84.6%), human adenovirus 7.7% (95% CI 2.6-15.0, I2 91.0%), influenza virus6.5% (95% CI 2.2-12.6, I2 92.4%), human metapneumovirus5.8% (95% CI 3.4-8.8, I2 89.0%), enterovirus 4.3% (95% CI 0.1-12.9, I2 96.2%), human parainfluenza virus 3.8% (95% CI 1.5-6.9, I2 79.1%), and human coronavirus 2.2% (95% CI 0.6-4.4, I2 79.4%). CONCLUSIONS: Our results suggest that rhinovirus and respiratory syncytial virus may contribute to the etiology of wheezing in children. While the clinical implications of molecular detection of respiratory viruses remains an interesting question, this study helps to illuminate the potential of role respiratory viruses in pediatric wheezing. REVIEW REGISTRATION: PROSPERO, CRD42018115128.

Systematic review and meta-analysis of the epidemiology of Lassa virus in humans, rodents and other mammals in sub-Saharan Africa.

Accurate data on the Lassa virus (LASV) human case fatality rate (CFR) and the prevalence of LASV in humans, rodents and other mammals are needed for better planning of actions that will ultimately reduce the burden of LASV infection in sub-Saharan Africa. In this systematic review with meta-analysis, we searched PubMed, Scopus, Africa Journal Online, and African Index Medicus from 1969 to 2020 to obtain studies that reported enough data to calculate LASV infection CFR or prevalence. Study selection, data extraction, and risk of bias assessment were conducted independently. We extracted all measures of current, recent, and past infections with LASV. Prevalence and CFR estimates were pooled using a random-effect meta-analysis. Factors associated with CFR, prevalence, and sources of between-study heterogeneity were determined using subgroup and metaregression analyses. This review was registered with PROSPERO, CRD42020166465. We initially identified 1,399 records and finally retained 109 reports that contributed to 291 prevalence records from 25 countries. The overall CFR was 29.7% (22.3-37.5) in humans. Pooled prevalence of LASV infection was 8.7% (95% confidence interval: 6.8-10.8) in humans, 3.2% (1.9-4.6) in rodents, and 0.7% (0.0-2.3) in other mammals. Subgroup and metaregression analyses revealed a substantial statistical heterogeneity explained by higher prevalence in tissue organs, in case-control, in hospital outbreak, and surveys, in retrospective studies, in urban and hospital setting, in hospitalized patients, and in West African countries. This study suggests that LASV infections is an important cause of death in humans and that LASV are common in humans, rodents and other mammals in sub-Saharan Africa. These estimates highlight disparities between sub-regions, and population risk profiles. Western Africa, and specific key populations were identified as having higher LASV CFR and prevalence, hence, deserving more attention for cost-effective preventive interventions.

Burden of hepatitis E virus infection in pregnancy and maternofoetal outcomes: a systematic review and meta-analysis.

BACKGROUND: There is still a dearth of knowledge on the burden of HEV infection in the global population of pregnant women. Therefore, we conducted a systematic review and meta-analysis to estimate the global burden of HEV infection in pregnancy. METHODS: We searched PubMed, Embase, Web of Knowledge, and Global Index Medicus to identify articles published until January 26, 2020. We considered cross-sectional, case-control, and cohort studies reporting the immunoglobulins M HEV seroprevalence in asymptomatic and symptomatic (jaundice or elevated transaminases) pregnant women or investigating the association between HEV infection and maternofoetal outcomes. We used a random-effects model to pool studies. This review was registered with PROSPERO, CRD42018093820. RESULTS: For HEV prevalence estimates, we included 52 studies (11,663 pregnant women). The seroprevalence was 3.5% (95% confidence interval: 1.4-6.4) in asymptomatic women (most of whom from high endemic areas). The prevalence in symptomatic women was 49.6% (42.6-56.7) with data only from HEV high endemic countries. In the multivariable meta-regression model, the prevalence was higher in symptomatic women compared to asymptomatic (adjusted prevalence odds ratio [aPOR]: 1.76; 95%CI: 1.61-1.91) and decreased with increasing year of publication (by 10-year) (aPOR: 0.90; 95%CI: 0.84-0.96). The proportion of HEV vertical transmission was 36.9% (13.3-64.2). Risk of bias was low, moderate and high respectively in 12 (23%), 37 (70%), and 4 studies (7%) addressing HEV prevalence estimation. HEV infection was associated with maternal deaths (pooled OR 7.17; 3.32-15.47), low birth weight (OR: 3.23; 1.71-6.10), small for gestational age (OR: 3.63; 1.25-10.49), preterm < 32 weeks (OR: 4.18; 1.23-14.20), and preterm < 37 weeks (OR: 3.45; 2.32-5.13), stillbirth (OR: 2.61; 1.64-4.14), intrauterine deaths (OR: 3.07; 2.13-4.43), and not with miscarriage (OR: 1.74; 0.77-3.90). All studies which assessed the association between HEV infection and maternofoetal outcomes had a moderate risk of bias. CONCLUSIONS: Findings from this study are suggestive of a high burden of HEV infection in pregnancy in high endemic countries, its association with poor maternofoetal outcomes, and a high rate of vertical transmission. This study supports the need for specific strategies to prevent exposure of pregnant women to HEV infection, especially in high endemic areas.

Association of early viral lower respiratory infections and subsequent development of atopy, a systematic review and meta-analysis of cohort studies.

INTRODUCTION: Existing evidence on the relationship between childhood lower respiratory tract infections (LRTI) and the subsequent atopy development is controversial. We aimed to investigate an association between viral LRTI at <5 years and the development of atopy at > 2 years. METHODS: We conducted a search at Embase, Pubmed, Web of Science, and Global Index Medicus. We collected data from the included articles. We estimated the odds ratio and the 95% confidence intervals with a random effect model. We determined factors associated with atopy development after childhood LRTI using univariate and multivariate meta-regression analyses. We recorded this systematic review at PROSPERO with the number CRD42018116955. RESULTS: We included 24 studies. There was no relationship between viral LRTI at <5 years and skin prick test-diagnosed-atopy (OR = 1.2, [95% CI = 0.7-2.0]), unknown diagnosed-atopy (OR = 0.7, [95% CI = 0.4-1.3]), atopic dermatitis (OR = 1.2, [95% CI = 0.9-1.6]), hyperreactivity to pollen (OR = 0.8, [95% CI = 0.3-2.7]), food (OR = 0.8, [95% CI = 0.3-2.5]), or house dust mite (OR = 1.1, [95% CI = 0.6-2.2]). Although not confirmed in all studies with a symmetric distribution of the 23 confounding factors investigated, the overall analyses showed that there was a relationship between childhood viral LRTI at < 5 years and serum test diagnosed-atopy (OR = 2.0, [95% CI = 1.0-4.1]), allergic rhinoconjunctivitis (OR = 1.7, [95% CI = 1.1-2.9]), hyperreactivity diagnosed by serum tests with food (OR = 5.3, [1.7-16.7]) or inhaled allergens (OR = 4.2, [95% CI = 2.1-8.5]), or furred animals (OR = 0.6, [95% CI = 0.5-0.9]). CONCLUSION: These results suggest that there is no association between viral LRTI at < 5 years and the majority of categories of atopy studied during this work. These results, however, are not confirmed for the remaining categories of atopy and more particularly those diagnosed by serum tests. There is a real need to develop more accurate atopy diagnostic tools.

Comparison of health care resource utilization among preterm and term infants hospitalized with Human Respiratory Syncytial Virus infections: A systematic review and meta-analysis of retrospective cohort studies.

INTRODUCTION: Data on the variation in the medical resource utilization rate of Human Respiratory Syncytial Virus (HRSV) infected children by gestational age have recently been made available. This review aimed to determine whether prematurity is independently associated with the use of medical resources in hospitalized children for HRSV infections. METHODS: We conducted this systematic review on cohort studies published on the medical resources use in preterm and full-term patients hospitalized for confirmed HRSV infections. We searched PubMed, Embase, and Global Index medicus for eligible studies. The standardized mean difference (SMD) and Risk Ratio (RR) with their 95% confidence intervals (95% CI) were estimated as summary statistics with random effects meta-analysis. The overall results were adjusted to the common confounders by stratified analyses. RESULTS: A total of 14 articles (20 studies) were included. Compared to full-term, preterm hospitalized with HRSV infections had more frequent intensive care unit admission (RR = 2.6, 95% CI = 1.9-3.5), increased length of stay in hospital (SMD = 0.6, 95% CI = 0.5-0.8) and intensive care unit (SMD = 0.6, 95% CI = 0.4-0.8) and increased case fatality rate (RR = 6.9, 95% CI = 2.0-23.8). Mechanical ventilation utilization was more frequent in preterm children ≤ 2 years (RR = 15.5, 95% CI = 8.9-26.4) and those who did not receive prophylaxis against HRSV (RR = 15.9, 95% CI = 9.1-27.9)] than in full-term children. No differences were identified in the frequency of emergency department visits, oxygen utilization, and the age at the first HRSV episode between preterm and full-term infants. CONCLUSIONS: Regardless of gestational age, preterm infants hospitalized for HRSV infections, especially those ≤ 2 years, have an increased frequency of use of health resources and poor outcomes compared to full-term infants. HRSV vaccine development programs for pregnant women should be accelerated. CLINICAL TRIALS REGISTRATION: Review registration PROSPERO, CRD42019124375.

Serological and molecular investigation of hepatitis E virus in pigs reservoirs from Cameroon reveals elevated seroprevalence and presence of genotype 3.

BACKGROUND: Hepatitis E virus (HEV) is a zoonotic pathogen of which pigs have been established as reservoirs. In the present study, we investigated the presence of HEV among pigs in the Center and Littoral regions of Cameroon and performed the molecular characterization of positive strains. METHODOLOGY: A total of 453 serum and stool samples were randomly collected from pigs in slaughterhouses in Obala, Douala and Yaounde. All samples were examined for the presence of anti-HEV IgG and IgM antibodies using ELISA assays. IgM positive stool samples were tested for HEV RNA using an RT-PCR assay, followed by a nested PCR assay for sequencing and phylogenetic analysis. RESULTS: Overall, 216 samples (47.7%, 95% CI: 43.1%-52.3%) were positive for at least one of the serological markers of HEV infection. Amongst these, 21.0% were positives for anti-HEV IgM, 17.7% for anti-HEV IgG, and 9.1% for both. A total of eight stool samples (5.9%) were positive for HEV RNA by nested RT-PCR. Phylogenetic analysis showed that the retrieved sequences clustered within HEV genotype 3. CONCLUSION: This study shows a high prevalence of anti-HEV antibodies and the circulation of genotype 3 in the swine population in Cameroon. Subsequent studies will be needed to elucidate the zoonotic transmission of HEV from pigs to humans in Cameroon.

Detection of hepatitis E virus antibodies among Cercopithecidae and Hominidae monkeys in Cameroon.

We screened hepatitis E from 15 species of non-human primates. Anti-HEV IgG was detected in 11.1% (1/9) Mandrillus sphinx, 14.3% (2/14) Gorilla gorilla, 5.9% (4/67) pan troglodytes and 8.7% (2/23) Mandrillus leucophaeus, whereas anti-HEV IgM was detected in 1.5% (1/18) papio Anubis, 28.6% (2/7) Cercocebus agilis and 1.5% (1/67) pan troglodyte.

Epidemiology of hepatitis E virus infection in animals in Africa: a systematic review and meta-analysis protocol.

BACKGROUND: Hepatitis E virus (HEV) is one of the major causes of acute hepatitis in humans worldwide with a case-fatality rate of 1-4% in the general population that might reach 30% in pregnant women. In the past decade in Africa, studies have shown that HEV infects not only humans but also animals. A systematic review summarizing the epidemiological data of HEV has been only performed in humans residing in Africa. We will perform this systematic review and meta-analysis to assess the prevalence of HEV infection in animal species in Africa. METHODS: This review will include cross-sectional studies among different animal species that reported the prevalence of HEV in Africa. We will consider published and unpublished studies from January 1, 2000 to present. A comprehensive search of PubMed, Excerpta Medica, African Journals Online, and Africa Index Medicus will be conducted to identify all relevant articles. Reference lists of eligible items and relevant articles will be reviewed. The funnel plots and the Egger test will be used to assess the publication bias. Study-specific estimates will be aggregated using a DerSimonian and Laird random-effects meta-analysis model to obtain an overall summary estimate of HEV prevalence across studies. The heterogeneity of the studies will be evaluated by the χ2 test on the Cochran's Q test. The results will be presented by animal species. DISCUSSION: HEV-infected animals are likely to transmit this virus to humans in Africa, as studies have already shown in developed countries. This systematic review and meta-analysis will provide a clear picture of the epidemiology of HEV in animals in Africa, to better understand this infection and to respond adequately to the epidemic challenges that often afflict Africa. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, CRD42018087684 .

Epidemiology of respiratory viral infections in people with acute respiratory tract infections in Africa: the VARIAFRICA systematic review and meta-analysis protocol.

INTRODUCTION: Better characterisation of the epidemiological data on respiratory viral infections among people with acute respiratory tract infection (ARTI) can help to implement efficient strategies to curb the burden of ARTI in Africa. We will conduct a systematic review and meta-analysis to determine the prevalence and factors associated with respiratory viral infection in people of all ages with ARTI residing in Africa. METHODS: This work will include cross-sectional studies published between January 1, 2000 and December 31, 2017, without any language restriction, on populations residing in African countries. We will consider studies that reported the prevalence of respiratory viruses in people with ARTI confirmed by a polymerase chain reaction technique. We will be searching PubMed, Embase, African Journals Online, Web of Science, and Global Index Medicus. The selection of relevant studies, extraction of data, and evaluation of the quality of the articles will be carried out independently by two review authors, and the discrepancies will be resolved by consensus or intervention of a third author. The heterogeneity of the studies will be assessed using the χ2 test on Cochrane's Q statistic. Publication bias will be assessed by the Egger test. Studies will be pooled using a random-effect meta-analysis model. Results will be presented by age group and sub-region of Africa. Using meta-regression models, we will identify factors associated with viral infections in people with ARTI. DISCUSSION: This systematic review and meta-analysis is based on published data and therefore does not require ethical approval. This work will serve as a basis for the development of strategies for prevention and control ARTI in Africa and will also serve to identify data gaps and guide future investigations. The final report will be published in peer-reviewed journals as a scientific article and presented in workshops, conferences, and scientific conferences. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, CRD42018088261 .

High seroprevalence of hepatitis E among pigs suggests an animal reservoir in Cameroon.

INTRODUCTION: Hepatitis E virus (HEV) is one of the most prevalent cause of acute hepatitis in humans worldwide. The risk of HEV transmission is not limited only to spread from human to human but the infection can also spread from animals to humans, especially from the domestic pigs. Despite mounting evidence regarding the zoonotic potential of porcine HEV infection, there are limited data on its prevalence in pigs in the sub-Sahara Africa region. Therefore, the present study aimed to determine the seroprevalence of HEV antibodies among pigs in two Cameroonian regions. METHODOLOGY: A total of 162 sera were collected from slaughtered-age pigs from January to March 2012. To determine whether pigs might represent a HEV reservoir in the Northern and Western region in Cameroon, anti-HEV IgG and IgM were tested by ELISA using commercials available kits. RESULTS: Overall, 70 of the 162 samples (43.2%, 95% CI: 35.5% - 51.2%) were positive for at least one of the serological markers of HEV infection (IgM and / or IgG).We observed a significant seroprevalence of HEV antibodies between the northern and western regions (60% (42/70) and 40% (28/70), p = 0.01796) respectively. CONCLUSION: Overall, this study reports a high seroprevalence of Hepatitis E virus antibodies in slaughter pigs in Cameroon. Our findings suggest that pigs might be a cause of zoonotic HEV transmission in Cameroon. Therefore, further studies are warranted to establish the dynamics of zoonotic HEV and characterize the different genotypes circulating in humans and pigs.