[Article in Chinese]
           Zhou B, Jia L, Xu X
           Chengdu Biological Products Institute.
           Chung Hua Liu Hsing Ping Hsueh Tsa Chih 1999
           Feb;20(1):38-41

        OBJECTIVE: To measure the safety and epidemiological efficacy of
        Japanese encephalitis live vaccine(SA14-14-2). METHODS: Guoyang and
        Mengcheng counties in Anhui Province, were chosen as observed spots
        where high incidence of JE was noticed in China. 1-6 years old children
        in two counties were inoculated with vaccine manufactured by Chengdu
        Biological Products Institute in the beginning of 1992. All children of
        1-6 years old received one primary dose of live vaccine and the children
        at one or two years old were respectively given one dose for primary or
        booster vaccination in 1993-1996. Side effects of live vaccine had been
        under surveillance for five years for its safety JE cases during the
        epidemic season (Jun to October), were diagnosed clinically and
        serologically. RESULTS: Data on the safety and efficacy of the JE live
        vaccine(SA14-14-2) are listed as follows:1) During 1992-1996, a total
        number, of 335,941 children at 1-6 year old were vaccinated. No
        vaccine-associated encephalitis, meningitis or other serious adverse
        events were observed. 2) The incidence of JE case has greatly declined
        since the beginning of large-scale vaccination. The average JE morbidity
        dcreased from 11.34/100,000 in 1987-1991 to 2.74/100,000 in 1992-1996(P
        < 0.005). 3) The incidence of JE case in 1-6 years old in that period
        reduced as well. The average JE morbidity decreased from 56.24/100,000
        to 13.83/100,000 in Guoyang and from 44.57/100,000 to 16.94/100,000 in
        Mengcheng counties respectively(P < 0.005). Most of the JE cases (94%)
        occurred in the unvaccinated children including all the 18 death cases.
        4) Serum antibody response to immunization were measured by plaque
        reduction neutralization test. Neutralizing antibody seroconversion
        after one single vaccination were 83.87%-94.74%. CONCLUSION:
        The results further confirmed that JE live vaccine is safe for children and
        effective for prevention from JE disease in JE endemic areas.