At the start of the coronavirus epidemic in the Netherlands, there was a high incidence of COVID-19 in the eastern part of the province of Noord-Brabant. The affected area overlapped the region where cases of Q fever were common from 2007 to 2010. The geographical overlap was noted during the first wave of COVID-19. For that reason, RIVM investigated whether people who previously had Q fever had an increased risk of contracting COVID-19, and whether they had a more serious course of illness from COVID-19.