Tuberculosis As a Re-emerging Infectious Disease

Abstract

As in many Western countries, tuberculosis has become a re-emerging infectious disease in Japan recently. Discussions have been held from the epidemiological point of view highlighting the recent characteristics of the problem and the most effective ways of combatting it.
Infection: The steep and long-lasting decline in the risk of tuberculosis infection after the war has brought about a kind generation gap : a younger generation that has been only sparsely infected, and a older generation that has been heavily infected. This gap plays an important role in the increasing occurrence of small epidemics of tuberculosis.
Clinical development: The main source of the disease in recent years is the old generation that was infected decades ago. The prevention of the disease and its early detection in this age segment has been neglected until now. Enhancing treatment of latent tuberculosis infection, or chemoprophylaxis, is an important alternative to BCG vaccination. Teaching about tuberculosis to medical students and doctors will be increasingly important in order to maintain the alertness of the medical profession for the purpose of the early case-detection of tuberculosis. Also, for active case-detection or screening, indiscriminate mass miniature radiophotography services should be replaced with selective ones, i.e., contact examinations and screening for high risk individuals from a socio-economic point of view.
Clinical course: There is a clear drift of tuberculosis occurrence to the medically and socio-economically weaker segments of the population, as well as to older people, which will further deteriorate the prognosis of these patients. Case management for regular drug therapy will be of critical importance and should be strengthened, as in DOTS strategies in Western and developing countries since 1990s.