| Abstract: | A middle-scale epidemic of measles was occurred in Chiba Prefecture, from the beginning of the year in 2000 to September. The Chiba epidemiological surveillance of tuberculosis and infectious diseases committee conducted an investigation of the vaccination history of measles patients, to obtain the prevailing situation of measles and the efficacy of the vaccination. This report summarized results of the epidemiological investigation of measles vaccination history. A total of 1,665 cases were reported during the period. The ratio of the under 1-year-old (who usually do not receive measles vaccine) to all reported cases was 11.4%. The ratio of the vaccinees for the reported cases was 11.8% and this ratio increased in the 5 years old or over. In particular, the 9-year-old age group (26.2%), and 10-14-year-old age group (23.3%) showed a higher ratio than the other age groups. These results indicate that early vaccine inoculation to the under 1-year old group and improvement of the vaccination rate are necessary to prevent measles epidemic. The results also suggest revaccination to higher age groups might be effective. |
