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Monkeypox is an emerging infectious disease, which has a clinical presentation similar to smallpox. In the two past decades, Central Africa has seen an increase in the frequency of cases, with many monkeypox virus (MPXV) isolates detected in the Democratic Republic of Congo (DRC) and the Central African Republic (CAR). To date, no complete MPXV viral genome has been published from the human cases identified in the CAR. The objective of this study was to sequence the full genome of 10 MPXV isolates collected during the CAR epidemics between 2001 and 2018 in order to determine their phylogenetic relationships among MPXV lineages previously described in Central Africa and West Africa. Our phylogenetic results indicate that the 10 CAR isolates belong to three lineages closely related to those found in DRC. The phylogenetic pattern shows that all of them emerged in the rainforest block of the Congo Basin. Since most human index cases in CAR occurred at the northern edge of western and eastern rainforests, transmissions from wild animals living in the rainforest is the most probable hypothesis. In addition, molecular dating estimates suggest that periods of intense political instability resulting in population movements within the country often associated also with increased poverty may have led to more frequent contact with host wild animals. The CAR socio-economic situation, armed conflicts and ecological disturbances will likely incite populations to interact more and more with wild animals and thus increase the risk of zoonotic spillover. [ABSTRACT FROM AUTHOR]

Background: Rift Valley fever virus (RVFV) causes a viral zoonosis, with discontinuous epizootics and sporadic epidemics, essentially in East Africa. Infection with this virus causes severe illness and abortion in sheep, goats, and cattle as well as other domestic animals. Humans can also be exposed through close contact with infectious tissues or by bites from infected mosquitoes, primarily of the Aedes and Culex genuses. Although the cycle of RVFV infection in savannah regions is well documented, its distribution in forest areas in central Africa has been poorly investigated. Methodology/Principal Findings: To evaluate current circulation of RVFV among livestock and humans living in the Central African Republic (CAR), blood samples were collected from sheep, cattle, and goats and from people at risk, such as stock breeders and workers in slaughterhouses and livestock markets. The samples were tested for anti-RVFV immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies. We also sequenced the complete genomes of two local strains, one isolated in 1969 from mosquitoes and one isolated in 1985 from humans living in forested areas. The 1271 animals sampled comprised 727 cattle, 325 sheep, and 219 goats at three sites. The overall seroprevalence of anti-RVFV IgM antibodies was 1.9% and that of IgG antibodies was 8.6%. IgM antibodies were found only during the rainy season, but the frequency of IgG antibodies did not differ significantly by season. No evidence of recent RVFV infection was found in 335 people considered at risk; however, 16.7% had evidence of past infection. Comparison of the nucleotide sequences of the strains isolated in the CAR with those isolated in other African countries showed that they belonged to the East/Central African cluster. Conclusion and significance: This study confirms current circulation of RVFV in CAR. Further studies are needed to determine the potential vectors involved and the virus reservoirs. [ABSTRACT FROM AUTHOR]

The Bunyaviridae family is currently composed of five genera, including Phlebovirus, in which several phleboviruses are associated with human diseases. Using high-throughput sequencing, we obtained and characterized one complete genome of the Arumowot virus (AMTV) isolated in 1978 from Turdus libonyanus, the Kurrichane Thrush, in the Central African Republic (CAR). The genomic segment of the new strain of AMTV isolated in the CAR had 75.4-83.5% sequence similarity and 82-98.4% amino acid similarity to the prototype sequence of AMTV. The different conserved proteins of the small (S) and large (L) segments (Nc, NSP, and RNA polymerase) showed close similarity at the amino acid level, whereas the polyprotein of the medium (M) segment was highly divergent, with 18% and 37.7%, respectively, for the prototype sequence of AMTV and the Odrenisrou virus (ODRV) isolated from Culex (Cx.) albiventris mosquitoes in the Tai forest, Ivory Coast. Phylogenetic analysis confirmed the sequence homology analysis and indicated that AMTV-CAR clustered into the Salehabad virus antigenic complex. The two closest viruses were the prototype sequences of AMTV originally isolated from Cx. antennatus mosquitoes and ODRV. These molecular data suggest the need for a deep genetic characterization of the diversity of this viral species to enhance its detection in the Central African region and to understand better its behavior and life cycle so that its potential spread to the human population can be prevented. [ABSTRACT FROM AUTHOR]

Simian foamy virus (SFV) is a ubiquitous retrovirus in nonhuman primates (NHPs) that can be transmitted to humans, mostly through severe bites. In the past few years, our laboratory has identified more than 50 hunters from central Africa infected with zoonotic SFVs. Analysis of the complete sequences of five SFVs obtained from these individuals revealed that env was the most variable gene. Furthermore, recombinant SFV strains, some of which involve sequences in the env gene, were recently identified. Here, we investigated the variability of the env genes of zoonotic SFV strains and searched for possible recombinants. We sequenced the complete env gene or its surface glycoprotein region (SU) from DNA amplified from the blood of (i) a series of 40 individuals from Cameroon or Gabon infected with a gorilla or chimpanzee foamy virus (FV) strain and (ii) 1 gorilla and 3 infected chimpanzees living in the same areas as these hunters. Phylogenetic analyses revealed the existence of two env variants among both the gorilla and chimpanzee FV strains that were present in zoonotic and NHP strains. These variants differ greatly (>30% variability) in a 753-bp-long region located in the receptor-binding domain of SU, whereas the rest of the gene is very conserved. Although the organizations of the Env protein sequences are similar, the potential glycosylation patterns differ between variants. Analysis of recombination suggests that the variants emerged through recombination between different strains, although all parental strains could not be identified. [ABSTRACT FROM AUTHOR]

Abstract: Background: Intrafamilial and sexual transmission of hepatitis C virus (HCV) are still being debated, and little is known about such transmission in central Africa. Objective: To examine the rate of intrafamilial transmission of HCV between patients and their household members. Study design: A cross-sectional study was conducted in Dienga, a remote village in Gabon, involving 195 household members of 14 index cases of HCV infection. After a questionnaire on the risk factors for parenteral exposure, blood samples were obtained and tested for antibody to HCV by an enzyme immunoassay (Monolisa anti-HCV plus version 2). Positive samples were tested for HCV RNA and genotyped by amplification and phylogenetic analysis of a fragment of the NS5B gene. Results: HCV antibody was found in 13/195 (6.7%) household contacts, comprising 5/14 (35.7%) sexual partners and 8/114 (7%) relatives. None of the children of index patients tested positive. HCV RNA was detected in only five household members with HCV antibody. The same genotypes were found in only two of five couples, both couples being sexual partners. Parenteral risk factors were not more likely to be reported by people positive for HCV antibody than by those who were negative. Age over 50 years was the only independent predictor of positivity for HCV antibody. Conclusions: This study indicates, as previously suggested, that the spread of HCV in central Africa is due to a cohort effect, with previous, possibly iatrogenic, transmission rather than intrafamilial or sexual transmission. [Copyright &y& Elsevier]