SignificanceMiddle East respiratory syndrome (MERS) is a zoonotic disease of global health concern, and dromedary camels are the source of human infection. Although Africa has the largest number of dromedary camels, and MERS-coronavirus (MERS-CoV) is endemic in these camels, locally acquired zoonotic MERS is not reported from Africa. However, little is known of the genetic or phenotypic characterization of MERS-CoV from Africa. In this study we characterize MERS-CoV from Burkina Faso, Nigeria, Morocco, and Ethiopia. We demonstrate viral genetic and phenotypic differences in viruses from West Africa, which may be relevant to differences in zoonotic potential, highlighting the need for studies of MERS-CoV at the animal–human interface.

Evidence of current and past Middle East respiratory syndrome coronavirus (MERS-CoV) infection in dromedary camels slaughtered at an abattoir in Kano, Nigeria in January 2015, was sought by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and serology. MERS-CoV RNA was detected in 14 (11%) of 132 nasal swabs and antibody in 126 (96%) of 131 serum samples. Phylogenetic analyses demonstrate that the viruses in Nigeria are genetically distinct from those reported in the Arabian peninsula.

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Genetic recombination has frequently been observed in coronaviruses. Here, we sequenced multiple complete genomes of dromedary camel coronavirus HKU23 (DcCoV-HKU23) from Nigeria, Morocco, and Ethiopia and identified several genomic positions indicative of cross-species virus recombination events among other betacoronaviruses of the subgenus Embecovirus (clade A beta-CoVs). Recombinant fragments of a rabbit coronavirus (RbCoV-HKU14) were identified at the hemagglutinin esterase gene position. Homolog fragments of a rodent CoV were also observed at 8.9-kDa open reading frame 4a at the 3= end of the spike gene. The patterns of recombination differed geographically across the African region, highlighting a mosaic structure of DcCoV-HKU23 genomes circulating in dromedaries. Our results highlighted active recombination of coronaviruses circulating in dromedaries and are also relevant to the emergence and evolution of other betacoronaviruses, including Middle East respiratory syndrome coronavirus (MERS-CoV).IMPORTANCE Genetic recombination is often demonstrated in coronaviruses and can result in host range expansion or alteration in tissue tropism. Here, we showed interspecies events of recombination of an endemic dromedary camel coronavirus, HKU23, with other clade A betacoronaviruses. Our results supported the possibility that the zoonotic pathogen MERS-CoV, which also cocirculates in the same camel species, may have undergone similar recombination events facilitating its emergence or may do so in its future evolution.