First evidence of a new simian adenovirus clustering with Human mastadenovirus F viruses.

BACKGROUND: Adenoviruses play an important role as human pathogens, though most infections are believed to be asymptomatic. The over 100 human adenovirus types are classified into seven species (A-G), some of which include simian adenoviruses. Recent findings have highlighted that simian adenoviruses have a zoonotic potential and that some human adenoviruses are likely the result of relatively recent spillover events. METHODS: In order to evaluate the risks associated with primates hunted and sold as bushmeat, multiple samples from 24 freshly killed monkeys were collected in the Republic of the Congo and tested for adenovirus DNA by PCRs targeting the conserved DNA polymerase and hexon genes. RESULTS: The DNA of a novel simian adenovirus was detected in a moustached monkey (Cercopithecus cephus) by the DNA polymerase PCR, but not by the hexon PCR. The 275 nucleotide amplicon was most closely related to members of the Human mastadenovirus F species (93% HAdV-40 and 89% HAdV-41 amino acid identity), rather than to other known simian adenoviruses. CONCLUSIONS: The phylogenetic clustering with Human mastadenovirus F sequences suggests a common ancestor, more recent than the last common ancestor of humans and moustached monkeys. The findings increase concerns about the zoonotic potential of simian adenoviruses and highlight the need for more research and surveillance on the issue.

Orbivirus RNA in a Banana Serotine (Afronycteris nanus) Bat in the Republic of the Congo.

Orbiviruses are arthropod borne viruses of vertebrates, with some of them being important pathogens of veterinary, conservation and economic importance, while others are occasionally associated with human disease. Some apparently bat specific orbiviruses have been detected, but little is known about their distribution and diversity. We thus sampled and screened 52 bats living in the Congo Basin, and detected RNA indicative of a novel orbivirus in a single banana serotine (Afronycteris nanus) by PCR. The detected RNA clusters with epizootic haemorrhagic disease virus, bluetongue virus, and others. The findings highlight the need for more studies into arbovirus presence and diversity in bat species.

Sequences of Previously Unknown Rhabdoviruses Detected in Bat Samples from the Republic of the Congo.

The family Rhabdoviridae contains diverse viruses, including vector-borne and nonvector-borne viruses, some that are human pathogens, including rabies virus and also nonpathogenic viruses. Bats, which are a known reservoir of viruses with zoonotic potential including coronaviruses, also carry multiple rhabdoviruses such as but not limited to lyssaviruses. We collected samples from 193 insectivorous and frugivorous bats in the Republic of the Congo and tested them for rhabdovirus RNA. Four samples were found positive for viral RNA representing sequences of four different, not previously described rhabdoviruses. Although phylogenetic and taxonomic placement of the novel sequences is uncertain, similarities with previously detected rhabdovirus sequences in bats suggest that these could represent vertebrate viruses. Considering the pathogenic risks some rhabdoviruses pose for humans, these results highlight the need for more research and surveillance regarding rhabdoviruses and bats.

Coronavirus surveillance in wildlife from two Congo basin countries detects RNA of multiple species circulating in bats and rodents.

Coronaviruses play an important role as pathogens of humans and animals, and the emergence of epidemics like SARS, MERS and COVID-19 is closely linked to zoonotic transmission events primarily from wild animals. Bats have been found to be an important source of coronaviruses with some of them having the potential to infect humans, with other animals serving as intermediate or alternate hosts or reservoirs. Host diversity may be an important contributor to viral diversity and thus the potential for zoonotic events. To date, limited research has been done in Africa on this topic, in particular in the Congo Basin despite frequent contact between humans and wildlife in this region. We sampled and, using consensus coronavirus PCR-primers, tested 3,561 wild animals for coronavirus RNA. The focus was on bats (38%), rodents (38%), and primates (23%) that posed an elevated risk for contact with people, and we found coronavirus RNA in 121 animals, of which all but two were bats. Depending on the taxonomic family, bats were significantly more likely to be coronavirus RNA-positive when sampled either in the wet (Pteropodidae and Rhinolophidae) or dry season (Hipposideridae, Miniopteridae, Molossidae, and Vespertilionidae). The detected RNA sequences correspond to 15 alpha- and 6 betacoronaviruses, with some of them being very similar (>95% nucleotide identities) to known coronaviruses and others being more unique and potentially representing novel viruses. In seven of the bats, we detected RNA most closely related to sequences of the human common cold coronaviruses 229E or NL63 (>80% nucleotide identities). The findings highlight the potential for coronavirus spillover, especially in regions with a high diversity of bats and close human contact, and reinforces the need for ongoing surveillance.