[Herd immunity and the role of Chlamydia pneumoniae in the etiology of respiratory diseases in the Czech Republic].

The objective of the investigation was to assess the seroprevalence of IgG in the population of the Czech Republic and to assess the etiological role of Chlamydia pneumoniae in respiratory diseases. The sera were examined by specific tests-genus by ELISA and species by the microimmunofluorescent test. The examination of sera from 1974-1975 for the serological survey was selected to make the results comparable with the results of examinations planned for 1996. Chlamydia IgG were detected already in the age group from 1-4 years with a marked rise in youth, and in adult age the seroprevalence was between 72.0 and 86.2% (mean 80.1%). In the seropositivity of Chlamydia IgG participated mainly immunoglobulin C. pneumoniae, which was present already in child and school age (seroprevalence 7.7-88.2%), culminating in adult age (92.0-100%). IgG C. trachomatis were detected practically only in adult age, IgG C. psittaci were found only rarely in serum. In 16 subjects (of 216 examined) serological tests revealed acute (in 27 suspect), in 6 subjects recent (in 17 suspect) infection with C. pneumoniae and 53 to 63 subjects had the infection in the past.