[Epidemiological study on tuberculosis in Tochigi Prefecture. Part II: The changes in tuberculosis incidence and...

The incidence rate of tuberculosis has been increasing in recent 5 years in Tochigi Prefecture. The author intends to clarify the factors effecting the changes of tuberculosis incidence during the period from 1962 to 1987 by analyzing the annual statistics of tuberculosis registry and implementation of tuberculosis control programme. The results thus obtained are as follows: 1. The incidence rate of tuberculosis in Tochigi Prefecture has increased in the past 5 years especially in the younger age group of 0-19 and older age group of 50 and over. The increase can be explained by the recurrence of the disease occurred when they were young, most likely due to incomplete treatment, and secondary infection to young family contacts. 2. The positive rate of tubercle bacilli was higher in Tochigi Prefecture than the rate in whole Japan during the period from 1979 to 1983, which was resulted from the delay in detection. 3. Frequency of visits to patients by public health nurses, numbers of X-ray and bacteriological examinations had decreased during the same period when the incidence rate of tuberculosis increased. 4. Continuous efforts to reinforce the tuberculosis control programme, especially X-ray and bacteriological examination for high risk population, such as family contacts, cleaners and barbers is essential in Tochigi Prefecture.