Search

The main objectives of the present study were to investigate the clinical and laboratory features of meningococcal disease in the city of Rio de Janeiro, Brazil, during the overlap of 2 epidemics in the 1990s. We conducted a study of a series of cases of meningococcal disease admitted in a Meningitis Reference Hospital. All clinical isolates available were analyzed by means of microbiological epidemiological markers. In 1990, Neisseria meningitidis serogroup B:4,7:P1.19,15, 1.7,1 sulfadiazine-resistant of the ET-5 complex emerged causing epidemic disease. Despite mass vaccination campaign (VaMengoc B+C®), the ET-5 clone remained hyperendemic after the epidemic peaked. In 1993 to 1995, an epidemic of serogroup C belonged to the cluster A4 overlapped, with a significant shift in the age distribution toward older age groups and an increase of sepsis. Serogroup C epidemics are a recurrent problem in Rio de Janeiro, which can be hindered with the introduction of a conjugate vaccine. We hope the data presented here brings useful information to discuss vaccines strategies and early management of suspected cases.

We evaluated the bactericidal antibody response to Neisseria meningitidis serogroup B in convalescent patients (n=65) from bacterial meningitis. Patients infected with B meningococci were stratified according to their vaccination status (Cuban BC vaccine) into group 1 (immunized) (n=12) and group 2 (non-immunized) (n=15). The results suggested that antibody titers > or =2 (log(2)) indicate a specific immune response to N. meningitidis. In group 1, 64% of patients had a significant antibody titer (> or =2) in their acute sera against a B:4:P1.15 strain, compared to only 21% of group 2 patients. All patients from group 1 without bactericidal antibodies in their acute sera had a significant increase (at least 2-fold increase in log(2) titers) in antibody titers in their convalescent sera, in contrast, to only 27% of patients from group 2 (P=0.06). Using mutant strains lacking OMP1 or OMP5, it was shown that OMP1 was an important antigen recognized by immunized patients but not by non-immunized patients.