[Long-term monitoring of Neisseria meningitidis carrier state in the nasopharynx and seroprevalence of specific antibodies in immunized and non-immunized persons]. / Dlouhodobé sledování nosicství Neisseria meningitidis v nosohltanu a séroprevalence specifických protilátek u imunizovaných a neimunizovaných osob.

Long-term (three-month and one-year) follow-up of nasopharyngeal carriers of Neisseria meningitidis with a frequency of sample collection of once a week and once a month resp. in the healthy population with a mean age of 43 years revealed a 4.8% positivity (2 of 42 subjects). Carriership of the same phenotype and ET-genotype of the N. meningitidis group 29E was stable in one subject, while the other long-term carrier of N. meningitidis group B has changes of the phenotype as well as ET-genotype during the follow-up period. Double (after a 3-month interval) verification of the seroprevalence of specific antimeningococcal antibodies revealed in a group of immunized subjects (vaccine A and C) a considerable degree of anti A immunity. Anti A-seropositivity in subjects immunized within a three-year interval since vaccination was 100%, in those immunized within a four-year interval a decline to 66% was recorded. Anti C antibodies after vaccination within a three-year interval were recorded in 75% subjects, in vaccinated subjects the authors detected antibodies during the first year after vaccination in 86% of the subjects. Natural anti A antibodies of the lowest titre 1:6 were recorded in four non-vaccinated subjects (22%). Naturally acquired anti B antibodies (B:2a:P1.2,P1.5) and anti C (C:2a:P1.2,P1.5) were not detected in any of the subjects.

[Increased incidence of invasive meningococcal disease caused by C:2a:P1.2 meningococci in certain regions of the Czech Republic]. / Zvýsený výskyt invazívního meningokokového onemocnení v nekterých oblastech Ceské republiky zpusobený meningokokem C:2a:P1.2.

In the first half of 1993 an increased incidence of invasive meningococcal disease was recorded in the Czech Republic. In the CR a total of 59 cases were revealed, incl. 10 fatal ones. This high lethality (16.9%) is markedly higher than that from 036 recorded in this country during previous years. The highest incidence and death rate was recorded in the North Moravian region and in the age group from 15-19 years. Based on active surveillance of the invasive meningococcal disease by epidemiologists, microbiologists and infectiologists of the entire Czech Republic, it may be concluded that the sulphonamide sensitive strain Neisseria meningitidis C:2a:P1.2 caused in the North Moravian region a local epidemic of invasive meningococcal disease in the army and civilian population. In other regions of the CR the epidemiological situation in the first half of 1993 did not differ from the previous period: sporadic incidence of meningococcal disease, prevalence of the serological group B, highest incidence in the youngest age groups. The meningococcus C:2a:P1.2 was not detected in the CR before 1993. This uncommon epidemiological situation was resolved by immunization, aimed from the antigenic aspect and with regard to age and locality.

Complex surveillance of Streptococcus pyogenes. II. Resistance in human blood and bactericidal activity receptors of field and collection streptococci.

A comparative study of a series of 31 epidemic streptococci and 36 collection M protein producers showed no statistically significant difference in their resistance in human blood. Even highly resistant field strains did not produce M protein (as the main bactericidal activity receptor) under laboratory conditions, however, although under natural conditions they left an anti-M response in the exposed population. Streptococcal resistance is not generally associated with M protein, but is influenced by another factor.