Forty years continous monitoring for bluetongue virus at an Australian site of high arbovirus activity. What have we achieved?

Abstract

Beatrice Hill Farm (BHF) near Darwin, Australia was identified in the early 1970's as a site of high arbovirus activity. The first isolation of Bluetongue virus (BTV) in Australia was made on BHF in 1975. Since then, there has been continuous monitoring for BTV at BHF, the virus has been isolated on a yearly basis, with the only exception of 1990. All 10 serotypes known in Australia have been isolated at this site and an assessment of their biological behaviour made. Over the years, the methods and intensity of monitoring have been changed. In recent years molecular techniques have permitted more detailed examination of the origins of the viruses and their natural behaviour in field situations. Data collected at BHF have allowed modelling to detect likely origins of the BTVs that regularly enter Australia through wind borne infected Culicoides from South East Asia. Concurrent vector monitoring led to assess the Culicoides species more likely to be involved with transmission of these viruses.