Leptospiral Infection in Common Brushtail Possums (Trichosurus Vulpecula) From Lowland Podocarp/Mixed Hardwood Forest in New Zealand.

Abstract

A survey of 261 common brushtail possums (Trichosurus vulpecula) from New Zealand lowland podocarp/mixed hardwood forest showed 34% of possums with antibodies to Leptospira interrogans serovar balcanica, 35% with antibodies to serovar hardjo, and isolation of balcanica leptospires from 23% of kidney cultures. One possum showed a titre to serovar ballum, leptospires of which were subsequently isolated in culture. Seroprevalences and isolation rates were similar in mature males and females, and increased with age. Sexually immature possums were rarely infected, but recently matured animals had significant rates of infection. Seroprevalence was elevated during the breeding season, suggesting that primary infections were generally acquired in association with sexual maturity and mating. There was no significant association between prevalence of infection and genotype, based on 8 polymorphic proteins. Infection had no significant effect on various indices of possum condition. In their response to infection, possums displayed characteristics typical of a maintenance host.