Rotavirus in Bats and Humans: Genetic Diversity and Gastroenteritis in the Post-Vaccine Era

For my doctoral project, I will focus on the rotavirus genetic diversity and impact of mass vaccination in Belgium. Rotaviruses are the major causes of gastroenteritis worldwide and two oral, live-attenuated vaccines are part of national immunization schedules in Belgium. It is crucial to monitor the genotype distribution of the wild-type strains, as mass vaccination might induce selective pressure and novel rotavirus strains emerge and spread fast on a global scale. It is also crucial to inspect the breakthrough cases, and to distinguish the ‘real’ breakthrough cases from another gastroenteritis causing viral pathogen(s), like norovirus and astrovirus, in order to accurately assess the vaccine efficacy and efficiency. Moreover, the potential circulation of the vaccine-derived strains in the human population should also be surveilled; as vaccine-derived strains have a possibility to infect unvaccinated infants. Another significant public health aspect is that rotaviruses have zoonotic potential; thus mammalian and avian strains need to be monitored continuously. In this study, we will use rotavirus surveillance to report on the genotype distribution in Belgium in the last decade, following large-scale vaccination. We will use NGS to determine the genotype constellations of breakthrough strains, characterize the acquired mutations and reassortment events in vaccine strains. We will try to investigate the real etiology by seeking for other potential viral pathogens that might be causing gastroenteritis. We will also explore novel rotavirus sequences in bats, possibly in other mammals and avian species, shedding light on rotavirus genetic evolution and providing better virus surveillance.