Invasive culture-confirmed Neisseria meningitidis in Portugal:: evaluation of serogroups in relation to different variables and antimicrobial susceptibility (2000-2001)

The first investigation of Neisseria meningitidis isolated from a large area covering an appreciable population in Portugal, before the voluntary vaccination period with the serogroup C conjugate vaccine, is reported. The serogroups and antimicrobial susceptibility of 116 isolates were studied. Serogroups C (50.0%), B (47.4%) and W135 (2.6%) were found. Serogroup C was most common in the 1-15-years-old group and B in the less than 1-year-old and over 16-years-old groups (P = 0.042). Clinical diagnosis of meningococcal disease was primarily meningitis for patients with serogroup C and meningitis associated with sepsis for those with serogroup B. Penicillin resistance was significantly associated with serogroup C (P < 0.001). This work reinforces the importance for public health of monitoring the serogroup and antimicrobial susceptibility of isolates from patients with invasive meningococcal disease.