A seroprevalence study to determine the frequency of hantavirus infection in people exposed to wild and pet fancy rats in England

Recent cases of acute kidney injury due to Seoul hantavirus infection from exposure to wild or pet fancy rats suggest this infection is increasing in prevalence in the UK. We conducted a seroprevalence study in England to estimate cumulative exposure in at-risk groups with contact with domesticated and wild rats to assess risk and inform public health advice. From October 2013 to June 2014, 844 individual blood samples were collected. Hantavirus seroprevalence amongst the pet fancy rat owner group was 34.1% (95% CI 23·9-45·7%) compared with 3·3% (95% CI 1·6-6·0) in a baseline control group, 2·4% in those with occupational exposure to pet fancy rats (95% CI 0·6-5·9) and 1·7% with occupational exposure to wild rats (95% CI 0·2-5·9). Variation in seroprevalence across groups with different exposure suggests that occupational exposure to pet and wild rats carries a very low risk, if any. However incidence of hantavirus infection among pet fancy rat owners/breeders, whether asymptomatic, undiagnosed mild viral illness or more severe disease may be very common and public health advice needs to be targeted to this at-risk group.