Cameroonian fruit bats harbor divergent viruses, including rotavirus H, bastroviruses, and picobirnaviruses using an alternative genetic code

Abstract

Most human emerging infectious diseases originate from wildlife and bats are a major reservoir of viruses, a few of which have been highly pathogenic to humans. In some regions of Cameroon, bats are hunted and eaten as a delicacy. This close proximity between human and bats provides ample opportunity for zoonotic events. To elucidate the viral diversity of Cameroonian fruit bats, we collected and metagenomically screened eighty-seven fecal samples of Eidolon helvum and Epomophorus gambianus fruit bats. The results showed a plethora of known and novel viruses. Phylogenetic analyses of the eleven gene segments of the first complete bat rotavirus H genome, showed clearly separated clusters of human, porcine, and bat rotavirus H strains, not indicating any recent interspecies transmission events. Additionally, we identified and analyzed a bat bastrovirus genome (a novel group of recently described viruses, related to astroviruses and hepatitis E viruses), confirming their recombinant nature, and provide further evidence of additional recombination events among bat bastroviruses. Interestingly, picobirnavirus-like RNA-dependent RNA polymerase gene segments were identified using an alternative mitochondrial genetic code, and further principal component analyses suggested that they may have a similar lifestyle to mitoviruses, a group of virus-like elements known to infect the mitochondria of fungi. Although identified bat coronavirus, parvovirus, and cyclovirus strains belong to established genera, most of the identified partitiviruses and densoviruses constitute putative novel genera in their respective families. Finally, the results of the phage community analyses of these bats indicate a very diverse geographically distinct bat phage population, probably reflecting different diets and gut bacterial ecosystems.

Viruses in bats and potential spillover to animals and humans

“…A plethora of known and novel viruses were identified in samples collected and metagenomically screened from straw-coloured fruit bat (Eidolon helvum) in Cameroon [98] and Neoromicia species in South Africa [99]. These bats were shown to harbor divergent viruses, including members of the families Astroviridae, Circoviruidae, Parvoviridae, Partitviridae, Coronaviridae, Picobirnavirdae, Adenoviridae, Herpesviridae, Papillomaviridae, Phenuiviridae, and Picornaviridae [98,99]. These recent studies build upon previous work [100][101][102][103] to further expand the diversity of the bat virome.…”

“…These recent studies build upon previous work [100][101][102][103] to further expand the diversity of the bat virome. Uniquely, the picobirnaviruses identified utilize an alternative genetic code [98].…”

“…Similarly, there are many other bat-borne viruses with the potential for zoonotic transmission, but without documented human infection. Rotaviruses and noroviruses, members of the families Reoviridae and Caliciviridae, respectively, are the major etiologic agents of acute gastroenteritis and several reports have identified rotavirus [98,99,[104][105][106] or norovirus [107,108]…”

Gut Virome Analysis of Cameroonians Reveals High Diversity of Enteric Viruses, Including Potential Interspecies Transmitted Viruses

“…Previously, we identified a plethora of known and novel eukaryotic viruses in Cameroonian fruit bats using a viral metagenomics approach, including viruses known to cause gastroenteritis in humans (sapovirus, sapelovirus, and rotaviruses A and H) and those not yet associated with gastroenteritis (bastrovirus and picobirna-like viruses) (20)(21)(22)(23). In the current study, we metagenomically screened 221 human fecal samples collected in the same region (where bats are hunted and eaten), to assess (i) if any viruses of animal origin could be identified and (ii) which known human gastrointestinal viruses were present.…”

MERS-CoV as an emerging respiratory illness: A review of prevention methods

“…The primary origin of both human and camel MERS-CoV is probably the vesper bats in Southern Africa [47][48][49]. The first transfer from bat to camel has likely occurred in Africa after a recombination event leading to genetic divergence in the original bat virus [4,7,10,48,[50][51][52][53]. MERS-CoV antibodies were detected in camel sera long before first human case reported [10,11].…”