Active surveillance of meningococcal meningitis in Poland.

Starting from 1970, the notification of N. meningitidis cases in Poland was compulsory and separated from other cases of meningitis purulenta. Based on the experience of European Monitoring Group on Meningococci, the active surveillance of meningococcal meningitis in Poland was initiated in April 1995. It was the first time that such study was conducted to recognise the actual situation of meningococcal meningitis infections in our country. Ninety seven N. meningitidis strains were isolated (31 in 1995 and 66 in 1996) from cerebrospinal fluid (CSF) of meningitis patients hospitalized in 54 hospitals located in 33 out of 49 provinces of Poland. Most patients were below 2 years of age and 43% belonged to infant group. Meningococcal strains were phenotypically characterized as follow: identification of N. meningitidis was performed by Gram staining, oxidase and catalase tests as well as latex or diagnostic sera agglutination assays. Meningococcal serotypes and subtypes were determined by whole-cell ELISA with monoclonal antibodies. The predominant meningococcal serogroup during 1995 and 1996 was B (80% of all isolates tested), the serogroup C (12.6%) and W-135 (3.5%). Only two non-groupable and two serogroup A strains were isolated in Poland. Active surveillance allowed to determine B:22:P1.14 to be the most prevalent N. meningitidis phenotype in Poland. Two isolates of N. meningitidis phenotype C:2a:P1.2,5, which caused emergency situation in Czech Republic since 1993, were isolated from CSF of patients in October 1996 in southern Poland. All strains were susceptible to cefotaxime, chloramphenicol, ciprofloxacin, rifampin and tetracycline; some strains were resistant to sulphonamides (60.6% - MIC = 32 mg/l and 14.8% - MIC = 128 mg/l). Only one of the tested strains in two years surveillance study in Poland was resistant to penicillin (MIC = 2 mg/l).