[On the epidemiology of recurrent and chronic bronchopulmonary diseases-an examination of about 18000 children. 3. Investigation in the district of Merseburg (author's transl)].

In the district of Merseburg, characterized by a very high degree of air pollution, we have examined 4445 children of the following 4 age-groups 5.-6., 8.-9., 11.-12., and 14.-16. years of life. As a result we found 3,04% of them suffering from recurrent bronchitis, 0,34% from chronic bronchitis and 0,43% from bronchial asthma. The frequency of morbidity on recurrent and chronic bronchitis lowered with increasing age of the children. In asthma, however, this relation did not exist. There were no differences of the frequency of chronic or recurrent bronchitis between the two sexes, but boys suffered much more often from asthma than girls. In places with a high degree of air pollution the frequency of morbidity was significantly higher than in places with somewhat lower air pollution.