JAPANESE ENCEPHALITIS SURVEILLANCE IN CHINA (PROVINCE OF TAIWAN) DURING 1968-1971

Abstract
A baseline age/morbidity pattern for the Japanese encephalitis (JE) epidemic in Taiwan in the 1960s was sought in JE surveillance. The pattern is characterized by high incidence in age groups 2-4 yr, moderately high incidence in age groups 5-7 yr, negligible incidence in children < 1 yr of age and in adults, and the variability of relative height of peak incidence co-incident with the JE-epidemic size in situ. Concurrently with surveillance, a JE-vaccination program was implemented. Children in target age groups received 2 doses of vaccine each year during April. Vigilant supervision was given to achieve a high converage rate with 2-dose vaccination and meticulous record-keeping. During 1969-1972, 2-yr olds were the exclusive target; 52.2% (1969), 71.5% (1970), 74.5% (1971) and 83.0% (1972) of the target age group were covered. A considerable change from the baseline age/morbidity pattern seen in 1968 occurred during the above period. The comparison of epidemicity-adjusted incidence by year indicates that incidence reduction in the 2- and 3-yr-old children in 1971 were substantial and suggests the possible impact of vaccination. The total JE incidence for the period 1968-1971 appears much lower in vaccinated population (23 reported and 8 confirmed/0.9 million) than in unvaccinated population (1330 reported and 679 confirmed/2.2 million).

This publication has 2 references indexed in Scilit: