Impact of the Australian Measles Control Campaign on immunity to measles and rubella

To evaluate the impact of the 1998 Australian Measles Control Campaign on i mmunity to measles and rubella, 4400 opportunistically-collected sera, subm itted to diagnostic laboratories across Australia from subjects aged 1-49 y ears, and 3000 from subjects aged 1-18 years, were tested before and after the campaign, respectively. The proportion of individuals aged 1-18 years w ho were immune to measles rose from 85% before, to 90% after, the campaign (P < 0.001). The greatest increase was in preschool (7%, P < 0.001) and pri mary school (10%, P < 0.001) children, who were actively targeted by the ca mpaign. Rubella immunity in 1-18 year-olds rose from 83% to 91% (P < 0.001) , again with significant increases in preschool (4%, P = 0.002) and primary school (16%, P < 0.001) children. 94% of individuals aged 19-49 years were immune to rubella. These serosurveys confirm other evidence of the effecti veness of the Australian Measles Control Campaign and demonstrate the value of serosurveillance using opportunistically collected sera.