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The increased research on bat coronaviruses after severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) allowed the very rapid identification of SARS-CoV-2. This is an excellent example of the importance of knowing viruses harbored by wildlife in general, and bats in particular, for global preparedness against emerging viral pathogens. Bats host many viruses pathogenic to humans, and increasing evidence suggests that rotavirus A (RVA) also belongs to this list. Rotaviruses cause diarrheal disease in many mammals and birds, and their segmented genomes allow them to reassort and increase their genetic diversity. Eighteen out of 2,142 bat fecal samples (0.8%) collected from Europe, Central America, and Africa were PCR-positive for RVA, and 11 of those were fully characterized using viral metagenomics. Upon contrasting their genomes with publicly available data, at least 7 distinct bat RVA genotype constellations (GCs) were identified, which included evidence of reassortments and 6 novel genotypes. Some of these constellations are spread across the world, whereas others appear to be geographically restricted. Our analyses also suggest that several unusual human and equine RVA strains might be of bat RVA origin, based on their phylogenetic clustering, despite various levels of nucleotide sequence identities between them. Although SA11 is one of the most widely used reference strains for RVA research and forms the backbone of a reverse genetics system, its origin remained enigmatic. Remarkably, the majority of the genotypes of SA11-like strains were shared with Gabonese bat RVAs, suggesting a potential common origin. Overall, our findings suggest an underexplored genetic diversity of RVAs in bats, which is likely only the tip of the iceberg. Increasing contact between humans and bat wildlife will further increase the zoonosis risk, which warrants closer attention to these viruses. IMPORTANCE The increased research on bat coronaviruses after severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) allowed the very rapid identification of SARS-CoV-2. This is an excellent example of the importance of knowing viruses harbored by wildlife in general, and bats in particular, for global preparedness against emerging viral pathogens. The current effort to characterize bat rotavirus strains from 3 continents sheds light on the vast genetic diversity of rotaviruses and also hints at a bat origin for several atypical rotaviruses in humans and animals, implying that zoonoses of bat rotaviruses might occur more frequently than currently realized.

Background Strengthening the surveillance of zoonotic diseases emergence in the wild meat value chains is a critical component of the prevention of future health crises. Community hunters could act as first-line observers in zoonotic pathogens surveillance systems in wildlife, by reporting early signs of the possible presence of a disease in the game animals they observe and manipulate on a regular basis. Methods An experimental game was developed and implemented in a forested area of Gabon, in central Africa. Our objective was to improve our understanding of community hunters' decision-making when finding signs of zoonotic diseases in game animals: would they report or dissimulate these findings to a health agency? 88 hunters, divided into 9 groups of 5 to 13 participants, participated in the game, which was run over 21 rounds. In each round the players participated in a simulated hunting trip during which they had a chance of capturing a wild animal displaying clinical signs of a zoonotic disease. When signs were visible, players had to decide whether to sell/consume the animal or to report it. The last option implied a lowered revenue from the hunt but an increased probability of early detection of zoonotic diseases with benefits for the entire group of hunters. Results The results showed that false alerts—i.e. a suspect case not caused by a zoonotic disease—led to a decrease in the number of reports in the next round (Odds Ratio [OR]: 0.46, 95% Confidence Interval [CI]: 0.36–0.8, p  < 0.01). Hunters who had an agricultural activity in addition to hunting reported suspect cases more often than others (OR: 2.05, 95% CI: 1.09–3.88, p  < 0.03). The number of suspect case reports increased with the rank of the game round (Incremental OR: 1.11, CI: 1.06–1.17, p  < 0.01) suggesting an increase in participants’ inclination to report throughout the game. Conclusion Using experimental games presents an added value for improving the understanding of people’s decisions to participate in health surveillance systems.

Background During the COVID-19 pandemic, many countries experienced successive waves marked by a substantial increase in cases. Across these waves, the characteristics of confirmed cases varied, particularly with respect to age, sex, and disease severity. Gabon, a country in Central African, experienced four successive pandemic waves between 2020 and 2022. In the Haut-Ogooué province, the first COVID-19 case was identified in early May 2020. This study aimed to describe the epidemiological patterns and profiles of COVID-19 cases across the first four waves of the pandemic, based on molecular diagnostic data collected between May 2020 and March 2022 in the Haut-Ogooué province of Gabon. Methods All individuals presenting with influenza-like illness or respiratory symptoms who attended a healthcare facility within the study area were included. Additionally, samples were collected from contact cases, as well as from departing and returning travelers. Samples from employees resuming work after vacation were also incorporated. SARS-CoV-2 diagnosis was performed using real-time reverse transcription polymerase chain reaction (RT-PCR), targeting the E gene and the RNA-dependent RNA polymerase gene. Data analysis was conducted using StatView version 5.0. Pearson’s Chi-square test and Fisher’s exact test were applied to compare patient demographic data during the four pandemic waves. Results The mean age of COVID-19 cases was 38.3 ± 14.2 years, which remained constant across the four pandemic waves. There was no significant difference between waves when comparing the proportion of infected men versus infected women, however, more than 50% of confirmed cases were male during the four waves ( p  < 0.0001). Individuals aged 25 to 54 years were the most affected across all periods. A high proportion of asymptomatic cases was consistently reported, ranging from 83.1% to 91.1% over the four waves ( p  < 0.0001). Conclusions The epidemiological profile of the four pandemic waves was similar, despite a decrease in positivity between the waves. The proportion of asymptomatic cases remained consistently high across all waves, as observed in many African countries. These findings provide important public health insights into the impact of COVID-19 on the population of Haut-Ogooué and Gabon.

Rift Valley fever (RVF) is a mosquito-borne viral zoonosis caused by the Rift Valley fever virus (RVFV) that can infect domestic and wild animals. Although the RVFV transmission cycle has been well documented across Africa in savanna ecosystems, little is known about its transmission in tropical rainforest settings, particularly in Central Africa. We therefore conducted a survey in northeastern Gabon to assess RVFV circulation among wild and domestic animals. Among 163 wildlife samples tested using RVFV-specific RT-qPCR, four ruminants belonging to subfamily Cephalophinae were detected positive. The phylogenetic analysis revealed that the four RVFV sequences clustered together with a virus isolated in Namibia within the well-structured Egyptian clade. A cross-sectional survey conducted on sheep, goats and dogs living in villages within the same area determined the IgG RVFV-specific antibody prevalence using cELISA. Out of the 306 small ruminants tested (214 goats, 92 sheep), an overall antibody prevalence of 15.4% (95% CI [11.5–19.9]) was observed with a higher rate in goats than in sheep (20.1% versus 3.3%). RVFV-specific antibodies were detected in a single dog out of the 26 tested. Neither age, sex of domestic animals nor season was found to be significant risk factors of RVFV occurrence. Our findings highlight sylvatic circulation of RVFV for the first time in Gabon. These results stress the need to develop adequate surveillance plan measures to better control the public health threat of RVFV.

The first detection of canine parvovirus type-2 (CPV-2) was in the early 1970s, when it was known to cause severe gastroenteritis in dogs. However, it has evolved over the years into CPV-2a within 2 years, into CPV-2b after 14 years, into CPV-2c after 16 years and more recently CPV-2a-, 2b- and 2c-like variants reported in 2019, with a global distribution. Reports on the molecular epidemiology of this virus are missing in most African countries. The report of clinical cases among vaccinated dogs in Libreville in Gabon triggered the execution of this study. The objective of this study was to characterize circulating variants from dogs showing clinical signs suggestive of CPV that were examined by a veterinarian. A total of eight (8) fecal swab samples were collected, and all had positive PCR results. Sequencing, Blast analysis and assembly of two whole genomes and eight partial VP2 sequences were performed, and the sequences submitted to GenBank. Genetic characterization revealed the presence of CPV-2a and CPV-2c variants with predominance of the former. Phylogenetically, the Gabonese CPVs formed distinct groups similar to Zambian CPV-2c and Australian CPV-2a sequences. The antigenic variants CPV-2a and CPV-2c have not yet been reported in Central Africa. However, these CPV-2 variants circulate in young, vaccinated dogs in Gabon. These results suggest additional epidemiological and genomic studies are required in order to evaluate the occurrence of different CPV variants in Gabon and effectiveness of the commercial vaccines used against protoparvovirus in the country.

Wild animals harbor pathogens that can be infectious agents for humans, including parasites. This study aimed to identify gastrointestinal parasites and assess their prevalence and the potential risk for humans associated with consuming these animals. The research was conducted from August to December 2019. Parasitological analyses were carried out on the feces and intestines of 113 wild animals, including antelopes (24), duikers (58), porcupines (18), small monkeys (Cercopithecus) (8), nandinia (2), pangolin (1), genet (1), and a crocodile (1), from the Zadié Department in the province of Ogooué-Ivindo in the northeast of Gabon. The results revealed 15 taxa of gastrointestinal parasites, including nine nematodes: Strongylids (61/113), Strongyloides spp. (21/113), Ascaris spp. (21/113), Trichuris spp. (39/113), Capillaria spp. (9/113), Protostrongylus spp. (5/113), Enterobius spp. (8/113), Toxocara spp. (7/113) and Mammomonogamus spp. (5/113); three species of protozoa, namely Balantidium spp. (12/113), Eimeria spp. (17/113), and Entamoeba spp. (9/113); two species of trematodes, namely Fasciola spp. (18/113) and Paramphistomum spp. (21/113); and cestode species, Taenia spp. (1/113). The prevalence of gastrointestinal parasitism in these animals was 85.84% (97/113). In addition, among these parasitic taxa, some are potential pathogens for humans, such as Ascaris spp., Balantidium spp., Entamoeba spp., and Taenia spp. The consumption of games, particularly offal, infested by these parasites, could threaten human health.

Background Evidence of haemosporidian infections in bats and bat flies has motivated a growing interest in characterizing their transmission cycles. In Gabon (Central Africa), many caves house massive colonies of bats that are known hosts of Polychromophilus Dionisi parasites, presumably transmitted by blood-sucking bat flies. However, the role of bat flies in bat malaria transmission remains under-documented. Methods An entomological survey was carried out in four caves in Gabon to investigate bat fly diversity, infestation rates and host preferences and to determine their role in Polychromophilus parasite transmission. Bat flies were sampled for 2–4 consecutive nights each month from February to April 2011 (Faucon and Zadie caves) and from May 2012 to April 2013 (Kessipoughou and Djibilong caves). Bat flies isolated from the fur of each captured bat were morphologically identified and screened for infection by haemosporidian parasites using primers targeting the mitochondrial cytochrome b gene. Results Among the 1,154 bats captured and identified as Miniopterus inflatus Thomas ( n  = 354) , Hipposideros caffer Sundevall complex ( n  = 285) , Hipposideros gigas Wagner ( n  = 317) , Rousettus aegyptiacus Geoffroy ( n  = 157 , and Coleura afra Peters ( n  = 41), 439 (38.0 %) were infested by bat flies. The 1,063 bat flies recovered from bats belonged to five taxa: Nycteribia schmidlii scotti Falcoz , Eucampsipoda africana Theodor, Penicillidia fulvida Bigot, Brachytarsina allaudi Falcoz and Raymondia huberi Frauenfeld group . The mean infestation rate varied significantly according to the bat species (ANOVA, F (4,75) = 13.15, P  < 0.001) and a strong association effect between bat fly species and host bat species was observed. Polychromophilus melanipherus Dionisi was mainly detected in N. s. scotti and P. fulvida and less frequently in E. africana, R. huberi group and B. allaudi bat flies. These results suggest that N. s. scotti and P. fulvida could potentially be involved in P. melanipherus transmission among cave-dwelling bats. Sequence analysis revealed eight haplotypes of P. melanipherus . Conclusions This work represents the first documented record of the cave-dwelling bat fly fauna in Gabon and significantly contributes to our understanding of bat fly host-feeding behavior and their respective roles in Polychromophilus transmission.

In 2014, Ebola virus (EBOV) was identified as the etiological agent of a large and still expanding outbreak of Ebola virus disease (EVD) in West Africa and a much more confined EVD outbreak in Middle Africa. Epidemiological and evolutionary analyses confirmed that all cases of both outbreaks are connected to a single introduction each of EBOV into human populations and that both outbreaks are not directly connected. Coding-complete genomic sequence analyses of isolates revealed that the two outbreaks were caused by two novel EBOV variants, and initial clinical observations suggest that neither of them should be considered strains. Here we present consensus decisions on naming for both variants (West Africa: “Makona”, Middle Africa: “Lomela”) and provide database-compatible full, shortened, and abbreviated names that are in line with recently established filovirus sub-species nomenclatures.

Caves house pathogenic microorganisms, some of which are transmitted by blood-sucking arthropods. In Africa, previous studies identified mosquitoes, sand flies and biting midges as the main potential vectors of cave-dwelling pathogens. However, to understand their involvement in pathogen spillover, it is crucial to characterize their diversity, community composition and dynamics. Using CDC light traps, we collected hematophagous Diptera in six caves of Gabon during one-shot or longitudinal sampling, and investigated their species diversity and dynamics in relation with external rainfall. Overall, we identified 68 species of mosquitoes, sand flies and biting midges, including 45 new records for Gabon. The dominant species were: Uranotaenia nigromaculata, Anopheles smithii s.l., Culex. rima group and Culex quasiguiarti for mosquitoes, Spelaeophlebotomus gigas and Spelaeomyia emilii for sand flies and the Culicoides trifasciellus group and Culicoides fulvithorax for biting midges. The survey revealed that species assemblages were cave-specific and included mainly troglophilous and trogloxenous species. Both diversity and abundance varied according to the cave and sampling time, and were significantly associated with rainfall. These associations were modulated by the cave specific environmental conditions. Moreover, the presence of trogloxenous and troglophilous species could be of high significance for pathogen transfers between cave and epigeous hosts, including humans.

IntroductionZoonotic diseases represent a major public health concern in Central Africa, where forest-dependent communities experience frequent contact with wildlife through hunting activities, bushmeat handling, consumption, and trade. This study assessed knowledge, attitudes, and practices related to zoonotic diseases among communities engaged in hunting practices, bushmeat consumption, and wildlife trade in Mulundu Department.MethodsA cross-sectional questionnaire-based survey was conducted from April 2023 to April 2024 among 326 participants from five communities. Data on sociodemographic characteristics, awareness of zoonoses, perceived transmission routes, clinical signs, attitudes, and preventive practices were collected through structured interviewer-administered questionnaires. Knowledge was assessed using 13 items and categorized into poor or good knowledge level. Associations between knowledge level and participant characteristics were examined using Pearson's chi-square tests and logistic regression.ResultsOverall, 72.7% of respondents had previously heard of zoonotic diseases, with Ebola being the most frequently identified. Most participants had poor knowledge overall (69.3%), while 30.7% had good knowledge. Knowledge level varied significantly by regroupement ( p = 0.037), and age ( p = 0.023). Attitudes toward prevention were generally positive, up to 31.0% of participants remained uncertain about how to respond appropriately in high-risk situations.DiscussionThese findings highlight important geographic and behavioral gaps in zoonotic disease preparedness and support the need for sustained, culturally adapted, community-based One Health interventions in rural communities in Gabon.