| Summary: | Thesis (PhD)--Stellenbosch University, 2020. ENGLISH ABSTRACT: Emerging infectious diseases are mostly zoonotic in origin and defined as “infections that have newly emerged in a population or have existed but are rapidly increasing in incidence or geographic range". Zoonotic viruses are directly (e.g. bite from a rabid bat) or indirectly (via an intermediate host or vector) transmitted from animals to humans. Bats have received increasing attention as potential hostsfor zoonotic diseases. Bats belong to the order Chiroptera, which consists of two suborders: Yinpterochiroptera and Yangochiroptera. More than 1 300 species have been described globally, occurring on almost all continents excluding Antarctica. Specific physiological and ecological characteristics make bats extraordinary evolutionary vessels to carry numerous infectious agents including pathogens. Astroviruses (AstVs) are amongst the vast array of viruses that have been detected in bats. AstVs are single stranded, positive sense, RNA viruses that are transmitted via the faecal-oral route. Infection with AstVs causes acute diarrhoea, however, more serious clinical presentations such as neurological deficits, stunted growth and encephalitis have also been documented. Bats on the other hand, seem to be asymptomatically infected with AstVs. Little attention has been given to the evolution, phylogenetic relationship, ecology and diversity of AstVs in South African bats. In 2013 the first study in South Africa screening for a variety of viruses in small mammals, including SAn bats, found that bats were frequently co-infected with AstVs and coronaviruses. The overall aims of the current study were to describe the prevalence, diversity and ecology of AstVs in South African bats, to determine the potential threat to environmental and animal health at wastewater treatment works (WWTW) through testing water and bat samples for the presence of AstVs, to monitor AstV and CoV co-infection in a Neoromicia capensis colony over time and to isolate and propagate a ...
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