Re-Emergence of Meningococcal Disease in Taiwan: Circulation of Domestic Clones of Neisseria Meningitidis in the 2001 Outbreak

Abstract

The annual incidence of meningococcal disease (meningitis and septicaemia ) in Taiwan was 0(.)94/10(5) population in 1953. It then declined to below 0(.)001 from 1980 to 1987, and re-emerged in 2000 with a rate of 0(.)07/ 10(5) population. In 2001 there was a further increase in incidence (43 cases, 0(.)19/10(5)). Of 43 isolates of Neisseria meningitidis available for this study, including 41 from patients treated in 200 1, three (7(.)0 %) were penicillin insensitive (MIC greater than or equal to 0(.)12 mug/ml ), though all were beta-lactamase negative; 16 (37(.)2 %) were resistant to trimethoprim-sulphamethoxazole (MIC greater than or equal to 4/76 mug/ ml). Serogrouping and genotype analysis revealed nine domestic clones. None of the 43 patients had any relationship (travel or contact history ) with the 2000 or 2001 Hajj pilgrimage. Epidemiological information and typing results suggested wide dissemination of a limited number of domestic clones of N. meningitidis, manifesting as serogroups W-135, B and Y. Two clones of serogroup W-135 involved in the outbreak were genetically distinct from the 2000 or 2001 Hajj-related W-135 clone.