SURVEILLANCE FOR ROSS RIVER VIRUS-INFECTION USING BLOOD-DONORS

The number of clinical Ross River virus (RRV) infections (epidemic pol yarthritis) each year in Australia continues to grow despite extensive vector control pro,srams. There is a need, therefore, for a surveilla nce program that can give sufficient warning of outbreaks of the disea se so that highly focused preventative measures may be undertaken. The ability of a surveillance program, based on voluntary Red Cross blood donations, to predict outbreaks of epidemic polyarthritis was evaluat ed. Anti-RRV IgM antibody was detected in significant numbers of blood donors from throughout the state of Queensland 6-9 weeks prior to an increase in the number of notified cases of epidemic polyarthritis. At a local level, significant numbers of anti-RRV IgM blood donors were detected in Brisbane in 1996 four weeks prior to an increase in the nu mber of notified cases of epidemic polyarthritis. This system of surve illance is technically simple, rapid (results are obtained in 2-3 days ), it samples the human population from throughout the state, and it g ives timely warning of outbreaks of epidemic polyarthritis.