Prevalence of serological groups of Neisseria meningitidis and their susceptibility to 31 antimicrobial agents.

One hundred and forty four strains of Neisseria meningitidis were isolated from pathological specimens and from carriers. The source of material was randomized in Poland. Out of seven existing serological groups of Neisseria meningitidis, no strains belonging to groups D and X were isolated. Serological group B was dominating; strains isolated from patients comprised 68%, while strains from carriers were group B-positive in 52%. Pathological specimens revealed presence of strains belonging to groups A, B and C only. All strains were tested toward susceptibility to 31 antimicrobials (8 penicillins, 5 cephalosporins, 3 tetracyclines, 4 sulphonamides and 11 other drugs). Most effective were: penicillin, carbenicillin, amoxycillin, cephalothin, and sulphonamides. Some sulphonamide-resistant strains, especially belonging to serological group C and to a lesser extent to group B, have been isolated.