ATYPICAL MYCOBACTERIA IN EXTRAPULMONARY DISEASE AMONG CHILDREN - INCIDENCE IN SWEDEN FROM 1969 TO 1990, RELATED TO CHANGING BCG-VACCINATIONCOVERAGE

Setting: In April 1975, the general BCG vaccination of newborns in Swe den was replaced by selective vaccination of groups at increased risk for tuberculosis. Objective: To relate the incidence of atypical mycob acterial disease in children to BCG vaccination. Design: A nationwide survey in Sweden during the period 1969-90 disclosed 390 children unde r 15 years of age with bacteriologically confirmed atypical mycobacter ia from extrapulmonary lesions. Results: The average, annual incidence of atypical mycobacterial disease per 100 000 children under 5 years of age increased from 0.06 during the period 1969-74 to a maximum leve l of 5.7 during 1981-85. Among the cohorts born in Sweden in the perio d 1975-85, the cumulative incidence rate before 5 years of age was est imated at 26.8 per 100 000 non-BCG-vaccinated children and at 4.6 amon g those BCG-vaccinated, ratio 5.9 (95% confidence limits 1.6, 48.5). M ycobacterium avium-intracellulare was found in 83%. Disseminated, fata l disease developed in 3 children. The remaining ones suffered from lo cal infections, most often lymphnode or soft-tissue lesions. The obser ved incidence of bacteriologically confirmed diagnosis was estimated t o represent approximately 40% of the 'true' number, if patients with d iagnosis based on histological, clinical and epidemiological findings only mere included. Conclusion: The present study indicates that BCG v accination plays a role in protection against localized disease caused by atypical mycobacteria in children.