[Herd immunity and the role of Chlamydia pneumoniae in the etiology of respiratory diseases in the Czech Republic]. / Promorenost a úloha Chlamydia pneumoniae v etiologii respiracních onemocnení v Ceské republice.

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.

[Parvovirus B 19 in pregnancy]. / Parvovirus B 19 v tehotenství.

The human parvovirus B 19 was discovered in 1975 by Cossart but its etiological association with erythema infectiosum and hydrops of the foetus was proved only in 1984-1985. The objective of the submitted prospective study was to assemble basic findings on the herd immunity of the female population and the risk of infection with this agent during pregnancy. Seropositivity of women of fertile age before the epidemic of parvovirus B 19 in 1993 and 1994 was cca 50%, after the epidemic 70%. Erythema infectiosum is a childhood disease (96% of the cases are children under 14 years of age), but seroprevalence of parvovirus IgG in these age groups is only 11%. Thus the infection in adults is frequent but not diagnosed. A parvovirus etiology of possible loss of the foetus on the basis of serological examination is encountered only exceptionally. The Czech commercial preparation gammaglobulin can be used for prevention and treatment of a non-immune foetal hydrops.

[Seroprevalence of IgG antibodies against parvovirus B19 in the population of the Czech Republic]. / Séroprevalence protilátek trídy IgG proti parvoviru B 19 v populaci Ceské republiky.

The human parvovirus B 19 was discovered in 1975 by Cossart in England. Later (1984) evidence was provided that this virus is the etiological agent of erythema infectiosum and hydrops foetalis, and in 1985 it was provided that it is also the etiological agent of some types of arthritis or arthropaties and vasculitis. The diagnosis of the disease caused by this agent is most frequently based on evidence of specific immunoglobulins. The epidemiological and clinical impact of parvoviral infections in the Czech Republic was not known so far. Examination of sera from 562 subjects aged 0-60 years assembled in 1992 in three Czech regions revealed in children, age 0 - 4 years 9.8%, during preschool and school age 27 - 35.7% and in age groups above 15 years a 53.3 - 57.7% seroprevalence of IgG parvovirus B 19, roughly equally distributed among both sexes. The more frequent prevalence of specific immunoglobulins was proved in small groups of female workers in nurseries (66.7%), nursery schools (91.7%) and in blood transfusion stations (77.8%). The seropositivity of the general female population of matched age groups, with the exception of women aged 20 - 24 years, was 53.86%.

Ecology and importance of bacterial' species of the family Vibrionaceae.

The bacterial species of the family Vibrionaceae, particularly the species of the genus Aeromonas (A. hydrophila and A. punctata and their subspecies were found to be relatively common in the running surface water in Czechoslovakia (the occurrence of A. salmonicida species was not studied). The strains of the so-called NAG-vibrios (Vibrio cholerae unrelated to the cholera vibrio 0 group 1) were also relatively frequent, but the positive isolates of Plesiomonas shigelloides were sporadic. The above described bacterial species occurred also in municipal sewage water and the strains of the Aeromonas genus were identified even in the drinking water of some wells and in foods. In the biological specimens from the human sources, namely in the feces of patients with diarrheal diseases, in secreta from the respiratory pathways, in the urine and occasionally in other material, there prevailed strains of the genus Aeromonas, especially A. hydrophila subsp. hydrophila and A. punctata subsp. caviae. Among the isolates from foods A. punctata subsp. caviae predominated. Positive isolates of the Aeromonas strains from the intestinal contents of cattle, domestic animals and some synantropic birds were rare. Importantly, a relatively great part of the isolates obtained from various sources (including the strains isolated from well water and foods) showed enterotoxigenic properties. The enterotoxigenicity was also observed in a great number of NAG-vibrio strains and in strains of Plesiomonas shigelloides. The occurrence of vibrios in the examined animal species was sporadic.