Abstract
While serological and virological evidence documents the exposure of bats to medically-important arboviruses, their role as reservoirs or amplifying hosts is less well-characterized. We describe a novel orbivirus (Reoviridae:Orbivirus) isolated from an Egyptian fruit bat (Rousettus aegyptiacus leachii) trapped in 2013 in Uganda and named Bukakata orbivirus. This is the fifth orbivirus isolated from a bat, however genetic information had previously only been available for one bat-associated orbivirus. We performed whole-genome sequencing on Bukakata orbivirus and three other bat-associated orbiviruses (Fomede, Ife, and Japanaut) to assess their phylogenetic relationship within the genus Orbivirus and develop hypotheses regarding potential arthropod vectors. Replication kinetics were assessed for Bukakata orbivirus in three different vertebrate cell lines. Lastly, qRT-PCR and nested PCR were used to determine the prevalence of Bukakata orbivirus RNA in archived samples from three populations of Egyptian fruit bats and one population of cave-associated soft ticks in Uganda. Complete coding sequences were obtained for all ten segments of Fomede, Ife, and Japanaut orbiviruses and for nine of the ten segments for Bukakata orbivirus. Phylogenetic analysis placed Bukakata and Fomede in the tick-borne orbivirus clade and Ife and Japanaut within the Culicoides/phlebotomine sandfly orbivirus clade. Further, Bukakata and Fomede appear to be serotypes of the Chobar Gorge virus species. Bukakata orbivirus replicated to high titers (106–107 PFU/mL) in Vero, BHK-21 [C-13], and R06E (Egyptian fruit bat) cells. Preliminary screening of archived bat and tick samples do not support Bukakata orbivirus presence in these collections, however additional testing is warranted given the phylogenetic associations observed. This study provided complete coding sequence for several bat-associated orbiviruses and in vitro characterization of a bat-associated orbivirus. Our results indicate that bats may play an important role in the epidemiology of viruses in the genus Orbivirus and further investigation is warranted into vector-host associations and ongoing surveillance efforts.
Highlights
Serological and virological evidence documents the exposure of various East African bat species to several arboviruses including Rift Valley fever, dengue, and yellow fever virus [1,2], little is known about the potential role of bats as arbovirus reservoirs or potential amplifying hosts
Of the additional tissues harvested from the infected bat and tested for BUKV, only liver and spleen were positive for infectious virus by plaque assay; lung, oral and fecal swabs, and intestine were negative
This study provided coding of the complete genome sequence on three bat-associated orbiviruses that have been discovered to date, and coding the complete sequence for nine of ten segments for a newly isolated bat-associated orbivirus
Summary
Serological and virological evidence documents the exposure of various East African bat species to several arboviruses including Rift Valley fever, dengue, and yellow fever virus [1,2], little is known about the potential role of bats as arbovirus reservoirs or potential amplifying hosts. Orbiviruses (Reoviridae:Orbivirus) are 10-segmented, dsRNA, vector-borne viruses that cluster phylogenetically by arthropod vector group [3]. Recent research has reported a novel orbivirus that may represent the first recognized insect-specific virus in the genus Orbivirus [4]. While mostly recognized as veterinary pathogens (i.e., bluetongue virus, African horse sickness), several orbiviruses have been associated with neurologic disease in humans [5,6,7,8].
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
