An Epidemiological Study on Measles Cases with Vaccination History of Measles Attenuated Live Vaccine

Objective To know the distribution characteristics of measles cases with vaccination history of measles attenuated live vaccine(MV)and to provide base data for Measles control and prevention.Methods A descriptive epidemiological study was conducted to analyze measles cases with or without vaccination history of measles attenuated vaccine reported in Zhejiang province in 2009.Results The confirmed measles cases with vaccination history of measles vaccine was obviously lower than(16.44%)non-measles cases(41.45%).The shortest interval between the latest MV vaccination and onset of measles case was 0d,the longest is 25 years,with a median of 3 months.The occurrence of Measles of interval proportions 1 month,1-11 months,1-9 years,10-25 years were 42.10%,30.19%,19.50%,6.92% respectively.The interval distribution was different by age groups.Some symptoms were milder in the cases with MV history than that without MV history.For cases with different interval between recent MV vaccination and onset of measles,conjunctivitis was less in those of 6-10d than others.Conclusion Measles cases with MV history could be resulted from primary or secondary immunization failure,or time vaccinated at the late incubation period.Few cases may actually be vaccine reactions at 6-10d after vaccination.