Clinical Manifestations of an Outbreak of Monkeypox Virus in Captive Chimpanzees in Cameroon, 2016.

Monkeypox virus (MPXV) is a reemerging virus of global concern. An outbreak of clade I MPXV affected 20 captive chimpanzees in Cameroon in 2016. We describe the epidemiology, virology, phylogenetics, and clinical progression of this outbreak. Clinical signs included exanthema, facial swelling, perilaryngeal swelling, and eschar. Mpox can be lethal in captive chimpanzees, with death likely resulting from respiratory complications. We advise avoiding anesthesia in animals with respiratory signs to reduce the likelihood of death. This outbreak presented a risk to animal care staff. There is a need for increased awareness and a One Health approach to preparation for outbreaks in wildlife rescue centers in primate range states where MPXV occurs. Control measures should include quarantining affected animals, limiting human contacts, surveillance of humans and animals, use of personal protective equipment, and regular decontamination of enclosures.

Prevalence and public health significance of rabies virus in bats in the North Region of Cameroon.

BACKGROUND: Rabies is a zoonotic disease of all warm-blooded animals including humans. There is a paucity of data on the status of rabies in wild animals in Cameroon and the disease is endemic in the country with dogs being the main source of transmission. Bat habitats are widespread in Cameroon, but there is limited information on the prevalence of rabies in bats, and their role of as potential reservoirs of rabies virus. METHODS: A cross sectional study was carried out to estimate the prevalence and to assess risk factors of rabies virus in bats in the North Region of Cameroon. A total of 212 bats belonging to three families (Pteropodidae, Vespertilionidae and Molossidae) and 5 species were sampled in 7 localities in the North Region of Cameroon and were tested for rabies virus antigen using direct Immunofluorescence Test (IFA). RESULTS: Overall, 26.9% (57/212) of the bats collected showed an IFA positive reaction. The prevalence was significantly higher (P<0.05) in adult bats (33.3% (36/108)) compared to young individuals (20.2%; 21/104). The main risk factors identified in the study for human exposure to bats were gender (Male), religion (Christianity), localities (Babla and Lagdo), the practice of bat hunting, bat consumption, unawareness of bat rabies and cohabitation with bats in close proximity. CONCLUSION: The study revealed the first evidence of Lyssavirus in bats in Cameroon. This finding showed that bat rabies are real and represents a potential public health concern in communities with bat habitats in the North Region of Cameroon. Enhancing the level of public awareness and health education on the potential of bats as reservoirs of Lyssavirus in Cameroon as well as the integration of the "One Health" approach for effective management of animal and human rabies should be emphasized.

Zoo-Sanitary Situation Assessment, an Initial Step in Country Disease Prioritization Process: Systematic Review and Meta-Analysis from 2000 to 2020 in Cameroon.

To prevent and/or control infectious diseases in animal and human health, an appropriate surveillance system based on suitable up-to-date epidemiological data is required. The systematic review protocol was designed according to the PRISMA statement to look at the available data on infectious diseases of livestock in Cameroon from 2000-2020. Data were searched through online databases. Grey literature was comprised of dissertations and theses from veterinary higher education institutions in Cameroon. A random-effects model was used to calculate pooled prevalence using Comprehensive Meta-Analysis Software. Based on disease prevalence, major infectious diseases of livestock in Cameroon were gastrointestinal parasitosis (57.4% in cattle, 67.2% in poultry, 88% in pigs), hemoparasites (21.6% in small ruminants, 19.7% in cattle), bovine pasteurellosis (55.5%), fowl salmonellosis (48.2%), small ruminant plague (39.7%), foot-and-mouth disease (34.5% in cattle), and African swine fever (18.9%). Furthermore, other important endemic zoonoses in the country included: Rift Valley fever (10.9% in cattle, 3.7% in small ruminants), brucellosis (7% in cattle, 8% in pigs), bovine tuberculosis (4.7% in cattle), hepatitis E virus (8.4% in pigs) and bovine leptospirosis (2.5%). Most of the retrieved research were carried out in the Adamawa, Northwest, and West regions of Cameroon. The evaluation of existing data as evidence, albeit publication-specific, is an important step towards the process of prioritizing animal diseases, including zoonoses.

Update on laboratory data of animal rabies at the Centre Pasteur of Cameroon from 2014 to 2021.

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.

Brucellosis in dairy herds: Farm characteristics and practices in relation to likely adoption of three potential private-public partnership (PPP) vaccination control strategies in West and Central Africa.

Brucellosis is regarded as one of the highest burden zoonotic diseases to persist in many regions globally. While sustained vaccination against B. abortus in an endemic setting can markedly reduce the prevalence of large ruminant and human brucellosis and benefit local livelihoods, the implementation of effective and sustainable control programmes has often failed in the worst affected areas. In a cross-sectional study of 728 peri-urban dairy farmers in nine areas of six West and Central African countries, levels of commercialization and farm characteristics were examined alongside B. abortus seroprevalence estimates to hypothesize the most appropriate model for brucellosis vaccination delivery in each country. Demographic and economic data were collated and used to describe the farming systems currently in place. Furthermore, these data were utilized in a likelihood assessment to generate a quantitative score to hypothesize which of three private-public partnership (PPP) vaccine delivery models, that is 1) transformative, 2) transactional or 3) collaborative, would be most appropriate in each setting. The study sites had substantial differences in their levels of dairy commercialization and the farming practices employed; the heterogeneity across the study sites was evident in the conclusions of which models would be appropriate for vaccination delivery. While Lomé (Togo) had a strong indication for a transformative PPP model, Burkina Faso had strong indication for the collaborative PPP model. Of the remaining study sites, the scores were less dominant for any one model with Cameroon and Ivory Coast sites only just scoring highest on the transformative model and Senegal and Mali sites only just scoring highest on the collaborative model. Interestingly, none of the countries included in the study scored highest on the transactional model which currently is the most commonplace delivery model in the majority of sub-Saharan African countries.

Critical Systematic Review of Zoonoses and Transboundary Animal Diseases' Prioritization in Africa.

BACKGROUND: Disease prioritization aims to enhance resource use efficiency concerning human and animal health systems' preparedness and response to the most important problems for the optimization of beneficial outcomes. In sub-Sahara Africa (SSA), several prioritizations of zoonoses and transboundary animal diseases (TADs) have been implemented at different scales to characterize potential disease impacts. Method and principal findings: In this systematic review, we analyze the methodologies used, outcomes, and their relevance by discussing criteria required to align decision-makers' perceptions of impacts to those of other stakeholders for different prioritization in SSA. In general, the sectorial representativeness of stakeholders for processes implemented with the support of international partners showed slight differences with the absence of local stakeholders. Whatever the tool prioritized, zoonoses were similar in general because of the structured nature of those tools in assessing decision-makers' preferences through value trade-offs between criteria while ensuring transparency and reproducibility. However, by involving field practitioners and farmers, there were different outcomes with processes concerning only decision makers and experts who were more sensitive to infectious TADs, while the former raised parasitic disease constraints. In this context, multicriteria decision analysis-based zoonoses and TADs prioritizations involving a balanced participation of stakeholders might contribute to bridging these divergences, whatever the scale. CONCLUSION AND SIGNIFICANCE: Prioritization processes were important steps toward building and harmonizing technical laboratory and surveillance networks to coordinate projects to address priority zoonoses and TADs at the country and/or sub-regional level. Those processes should be enhanced.

African swine fever in the northern regions of Cameroon: seroprevalence survey and spatiotemporal analysis of outbreaks from 2010 to 2017.

The present study was carried out to establish the spatiotemporal distribution of ASF between 2010 and 2017 in the Adamawa, North, and Far North regions of Cameroon. A retrospective study with data relating to the northern regions from epidemiological reports from target organizations in Cameroon was used to analyze outbreaks of ASF from 2010 to 2016. A prospective study consisting of risk factor analysis and serological investigation of anti-ASF antibodies and ASF RT-PCR antigen detection test in pig farms in the study regions with clinical suspicion of ASF was carried out in 2017. During the period 2010 to 2016, a total of 53 ASF outbreaks were reported and confirmed in the three northern regions of Cameroon and involved 4905 pigs (2232 deaths and 2673 slaughtered for sanitary measures). The seroprevalence for the 2017 serology survey was 5.23% (95% CI [3.57-6.89]) at the individual and 10.81% (95% CI [6.34-15.28]) at herd level. Region, management of farms system, on-farm slaughter by the owner (OR = 4.60; 95% CI [0.34-46.20]; p = 0.014), and selling of animals to community or to butchers (OR = 4.82; 95% CI [0.51-62.15]; p = 0.010) had significant effect on individual level seropositivity of ASF. The viral antigen was not detected by PCR. This study showed that ASF cases have decreased significantly in the northern regions of Cameroon following the epizootic 2010 outbreaks. The findings predict a better future for the pork farming in the regions through the enforcement of strategic measures.

Challenges of antimicrobial consumption surveillance in food-producing animals in sub-Saharan African countries: Patterns of antimicrobials imported in Cameroon from 2014 to 2019.

OBJECTIVE: Antimicrobial consumption surveillance is a useful tool for planning antimicrobial resistance control strategies and risk analysis. The present study was carried out to evaluate the consumption trends of antimicrobials for veterinary use in food-producing animals in Cameroon from 2014 to 2019. METHODS: Data on quantities of classes of active substances were collected from the records of the technical authorization to import veterinary drugs of suppliers' invoices at the Ministry of Livestock (MINEPIA); animal population data were collected from the FAO-Stat database. RESULTS: The study revealed that 217.67tonnes of antimicrobials (by weight of active substance) were imported during the 6-year period, with an average of 36.28±10.11tonnes per year. Tetracyclines (31.71%), sulfonamides (23.84%), quinolones (11.11%) and ß-lactams (10.17%) were the most commonly imported classes of antimicrobials. With regard to the importance of veterinary antimicrobials to human medicine, critically important antimicrobial (34.3%), reserve (4.6%) and watch (25.5%) groups as classified by the WHO AWaRe categorization were recorded. Overall, a mean of 5.24±1.40mg/PCU (population correction unit) was used in all food-producing animals during the 6-year period. However, the mean quantity of antimicrobials adjusted by animal biomass was highest in poultry (213.32±50.26mg/kg), followed by pigs (63.04±18.87mg/kg), cattle (4.11±2.20mg/kg), sheep (0.83±0.43mg/kg) and goats (0.47±0.24mg/kg). CONCLUSION: Strict surveillance systems of antimicrobial consumption in the country are vital to optimize control strategies. Monitoring importation data of veterinary antimicrobial products could be useful for sub-Saharan African countries to quantify consumption and estimate trends for antimicrobial usage effectively.

Veterinary pharmacovigilance in sub-Sahara Africa context: a pilot study of adverse reactions to veterinary medicine in Cameroon.

BACKGROUND: Sub-Saharan African market is highly affected by counterfeit veterinary drugs. Though these counterfeit and non-compliance of drugs can induce adverse effects during their utilization, there is no monitoring system of veterinary medicines. The present pilot study was carried out in Cameroon to identify and describe suspected cases of adverse reactions to veterinary drugs in animals and / or humans as well as inefficacy of veterinary drugs. The methodology involved a descriptive cross-sectional survey of 67 actors in the veterinary medicine sector in Cameroon. RESULTS: A total of 74/120 (62%) cases of suspected adverse effects and or lack of efficacy of veterinary drugs in animals and 46 (38%) cases of adverse reactions in humans were identified. Antiparasitics were the most incriminated therapeutic class in animals (61%) and human (56%). Adverse reactions were reported in dogs (44%) and poultry (24%) while drug inefficacy was most observed in poultry (47%). According to animal health professionals, levamisole (24%) and ivermectin (16%) were identified to be responsible for the adverse effects and that the highest level of inefficacy was most frequently reported for oxytetracycline (29%). The main adverse reactions were systemic (22%), gastrointestinal (20%) and neurological (13%) disorders. CONCLUSION: The results of this study showed that misuse and circulation of poor quality as well as lack of efficacy of veterinary drugs is very common in Cameroon. Adverse reactions were observed in animals and humans. Therefore, the establishment of a national veterinary pharmacovigilance system based on solid legal bases is essential for a continuous assessment of the risks-benefits effects of veterinary drugs marketed in Cameroon.

Antimicrobial resistance from a one health perspective in Cameroon: a systematic review and meta-analysis.

BACKGROUND: Antimicrobial resistance (AMR) is widely acknowledged as a global health problem, yet in many parts of the world its magnitude is not well elucidated. A baseline assessment of the AMR prevalence is a priority for implementation of laboratory-based AMR surveillance This review, focused on a One health approach, aimed at describing the current status of AMR in Cameroon. METHODS: PubMed, Google Scholar and African Journals Online databases were searched for articles published in English and French in accordance with the PRISMA guidelines. Retrieval and screening of article was done using a structured search string with strict inclusion/exclusion criteria. Free-text and grey literature were obtained by contacting the authors directly. The pooled prevalence and 95% confidence intervals were calculated for each pathogen-antibiotic pairs using random-effects models. RESULT: Amongst 97 full-text articles reviewed, 66 met the eligibility criteria. The studies originated from the Centre (24; 36.4%), South-West (16; 24.2%), West (13; 19.7%), Littoral (9; 13.6%) and other (4; 6.1%) regions of Cameroon. These studies reported AMR in human (45; 68.2%), animals (9; 13.6%) and the environment (12; 18.2%). Overall, 19 species of bacteria were tested against 48 antibiotics. These organisms were resistant to all classes of antibiotics and showed high levels of multidrug resistance. Escherichia coli, Klebsiella pneumoniae and Staphylococcus spp were reported in 23, 19 and 18 of the human studies and revealed multidrug resistance (MDR) rates of 47.1% [95% CI (37.3-57.2%)], 51.0% [95% CI (42.0-59.9)] and 45.2% [95% CI (38.0-54.7)], respectively. Salmonella spp was reported in 6 of the animal studies and showed a MDR rate of 46.2% [95% CI (39.2-53.5%)] while Staphylococcus spp in 8 of environment studies showed MDR rate of 67.1% [95% CI (55.2-77.2%)]. CONCLUSION: This review shows that resistance to commonly prescribed antibiotics in Cameroon is high. The findings emphasize the urgent need to address gaps in the standardization of AMR diagnostics, reporting and use of available information to optimize treatment guidelines for the arsenal of antibiotics. Effective AMR surveillance through continued data sharing, large-scale collaboration, and coordination of all stakeholders is essential to understand and manage the AMR national burden.

Brucellosis in dairy herds: A public health concern in the milk supply chains of West and Central Africa.

Ten herd-level cross-sectional studies were conducted in peri-urban dairy production areas of seven West and Central African countries (Burkina Faso, Burundi, Cameroon, Mali, Niger, Senegal and Togo). The objectives were to estimate herd level Brucella spp. seroprevalence and identify risk factors for seropositivity. In each of the ten study areas, herds (between 52 and 142 per area, total = 965) were selected probabilistically and a structured questionnaire was administered to gather information on their structure and management. A bulk milk sample from each herd was tested by indirect ELISA for Brucella spp. For each area, herd seroprevalence estimates were obtained after adjusting for the assumed performance of the diagnostic test. Herd level risk factors for Brucella spp. seropositivity were identified by means of stratified logistic regression, with each peri-urban zone as a stratum. Area-specific models were also explored. Estimated herd seroprevalences were: Lomé (Togo) 62.0% (95% CI:55.0-69.0), Bamako (Mali) 32.5% (95% CI:28.0-37.0), Bujumbura (Burundi) 14.7% (95%CI:9.4-20.8), Bamenda (Cameroon) 12.6% (95% CI:7.6-21.9), Ouagadougou (Burkina Faso) 3.0% (95% CI:1.0-9.1), Ngaoundere (Cameroon) 2.3% (95% CI:1.0-7.0), Thies (Senegal) 1.3% (95% CI:0.1, 5.3), Niamey (Niger) 1.2% (95% CI:0.08-5.3), Dakar (Senegal) 0.2% (95% CI:0.01-1.7) and Niakhar (Senegal) <0.04%. Logistic regression modelling revealed transhumant herds to be at lower risk of infection (adjusted OR: 0.25, 95% CI: 0.13 - 0.5) and in one of the areas (Bamenda), regular purchase of new animals was found to be strongly associated with Brucella spp. seropositivity (adjusted OR = 5.3, 95% CI: 1.4-25.9). Our findings confirm that Brucella spp. circulates among dairy cattle supplying milk to urban consumers in West and Central Africa, posing a serious public health concern. Control programs are urgently needed in areas such as Lomé or Bamako, where more than 30% of the herds show evidence of infection.

Evidence of exposure and human seroconversion during an outbreak of avian influenza A(H5N1) among poultry in Cameroon.

From May 2016 to March 2017, 22 poultry outbreaks of avian influenza A(H5N1) were reported in Cameroon, mainly in poultry farms and live bird markets. No human cases were reported. In this study, we sought to describe the 2016 A(H5N1) outbreak strain and to investigate the risk of infection in exposed individuals. We find that highly pathogenic influenza subtype A(H5N1), clade 2.3.2.1c from Cameroon is closely related phylogenetically and antigenically to strains isolated in central and western Africa at the time. No molecular markers of increased human transmissibility were noted; however, seroconversion was detected in two poultry workers (1.5% of total screened). Therefore, the continued outbreaks of avian influenza in poultry and the risk of zoonotic human infection highlight the crucial need for continued and vigilant influenza surveillance and research in Africa, especially in areas of high poultry trade, such as Cameroon.

A countrywide molecular survey leads to a seminal identification of the invasive cattle tick Rhipicephalus (Boophilus) microplus in Cameroon, a decade after it was reported in Cote d'Ivoire.

The cattle tick Rhipicephalus microplus is the most important arthropod vector of livestock diseases globally. Since its introduction in West Africa a decade ago, it has been reported in Ivory Coast, Benin, Togo, Mali, Burkina Faso and Nigeria with potentially far-reaching adverse impacts on the livestock sector in the region. Cameroon is located on a major route for transboundary cattle trade between Central and West Africa and it is therefore at risk from R. microplus invasion. This study investigated the occurrence of R. microplus in Cameroon, the genetic polymorphism of the tick and population structure of isolates from different regions of the country to provide data that underpin the design of future vector control programs. A cross-sectional survey was conducted in which ticks were collected from cattle at 54 sites across the five Agroecological zones (AEZs) within Cameroon. Tick identity (sex and species) was assigned using taxonomic keys. Species identity was confirmed through amplification and sequencing of the mitochondrial COI and 16S rRNA genes. A total of 7091 ticks were collected out of which 1112 (15.6%) were morphologically identified as R. microplus. The presence of R. microplus was confirmed in 4 out of 5 agroecological zones. Only two haplotypes were identified by both COI and 16S rRNA genes, indicating a very low divergence in the genetic structure of the R. microplus population in Cameroon. 16S rRNA sequence analysis revealed a new haplotype specific to Cameroon. Phylogenetic trees revealed that all isolates of R. microplus from Cameroon were grouped into the previously described Africa/Americas clade. Application of a niche modelling algorithm to R. microplus distribution in Cameroon predicted that suitable habitat for the tick extended into southern Nigeria. This study demonstrated for the first time the presence of R. microplus in Cameroon. Genetic diversity tests indicate that the tick has not evolved significantly since the initial introduction to West Africa. We suggest further longitudinal studies to better define the spatial and temporal expansion of the range of the tick and the drivers of this spread.