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Abstract: The increasing proportions of adult cases were observed in the recent measles outbreaks in Zhejiang Province, China. In order to identify the high-risk age groups of measles for targeted intervention, a seroprevalence survey of measles antibody was conducted among 1961 participants aged 0–60 years randomly selected by age-stratified purpose sampling, and the effect of revaccination program in secondary school was evaluated in Zhejiang Province. The adjusted overall seropositivity rate of measles was 88% (95% confidence interval [CI]: 86–89%) with geometric mean titers (GMT), 976±86mIU/ml. The seropositivity rate of measles was significantly lower in subjects aged 15–19 years than aged 5–9 years (90% vs 96%, χ 2 =5.21, p =0.022). Both seropositivity rate and GMT level of measles were higher in participants aged 10–14 years with ≥2 doses MCV than those with only 1 dose (95% vs 81%, 1276mIU/ml vs 666mIU/ml). The seropositivity rate increased from 91% to 100% after revaccination with MCV among 184 secondary school students. The proportions of measles cases aged ≥15 years were reduced gradually (χ 2 =55.47, p =0.000) from 2009 to 2011 after implementing the revaccination campaign on secondary school students since 2008. Our findings strongly suggested that a revaccination opportunity with MCV for adolescents helps to improve the population immunity, and it can be conducted effectively and practically in secondary school students. [Copyright &y& Elsevier]