[Relationship between pseudocroup and air pollutant burden of the inhaled air and weather].

An epidemiological study is presented to demonstrate, in addition to the viral aetiology, the influence of airpollution and various weather conditions to the incidence of croup. By means of a special statistic tool (baseline data curves) we could demonstrate that rapid changes in airpollutants (especially NO and NO2) are followed by increased occurrence of croup. In addition, the quotient NO2/NO seems to correlate directly to the O3 concentration. The noticeable influence of airpollution as well as changing climatic conditions demonstrate the multiform aetiology of croup.