Prevalence and stability of antibodies to the BK and JC polyomaviruses: a long-term longitudinal study of Australians.

Serology has been used to indicate past infection by the human polyomaviruses BK virus (BKV) and JC virus (JCV), because the site of primary infection is not established fully. Little is known about BKV and JCV antibody stability over time. We investigated BKV and JCV seroprevalence and antibody stability over time in an Australian population-based study. Serum was collected from 458 adults participating in a longitudinal skin cancer study in Queensland in 1992, 1993 and 1996, and 117 people had a fourth sample collected in 2003. Serum samples were analysed for BKV and JCV VP1 antibodies by multiplex detection using the Luminex platform. The seroprevalence for BKV and JCV over 4.5 years was 97 and 63 %, respectively. The BKV seroprevalence was 99 % in 25-60-year-olds, and 94 % in people older than 60 years. JCV seroprevalence was around 60 % in people younger than 50 years, 68 % in people 50-70 years of age and 64 % in people older than 70 years. BKV seroprevalence was very stable over 11 years, with 96 % of people staying seropositive and 2 % remaining seronegative. JCV antibody status over time was less stable; 57 % of participants remained seropositive and 31 % seronegative. The same proportion of people (4 % each) seroconverted, seroreverted or had fluctuating JCV antibody levels. These results confirm the previously believed stability of polyomavirus antibodies, with BKV antibodies being highly stable and JCV antibodies moderately so. Thus, a single measure can be used as a reasonable indicator of long-term antibody status in epidemiological studies aiming to understand associations between polyomaviruses and disease.