Changing epidemiology of group A streptococcal infection in the USA.
To see whether changes in the epidemiology of group A streptococcal disease in the USA have been accompanied by a corresponding change in serotype distribution, epidemiological and M-typing and T-typing data for 5193 strains sent to the Centers for Disease Control, Atlanta, between 1972 and 1988 were analysed. The proportions of M-types 1, 3, and 18 increased significantly during the study period. These M-types were more likely to be invasive, to cause fatal infection, and to occur in a cluster of infections than were other types. By contrast, the proportions of M-types 4 and 12 decreased; they were less invasive and were less likely to be found in clusters than were other types. These data suggest that changes in the epidemiology of group A streptococcal disease may be related to changes in the distribution of M-types causing infection.
Schwartz
B
B
Respiratory Diseases Branch, Centers for Disease Control, Atlanta, Georgia 30333.
Facklam
R R
RR
Breiman
R F
RF
D000328:Adult; D015982:Bias; D002648:Child; D005069:Evaluation Studies as Topic; D006801:Humans; D015994:Incidence; D012044:Regression Analysis; D012703:Serotyping; D013029:Space-Time Clustering; D013290:Streptococcal Infections / Q000453:epidemiology* / Q000382:microbiology / Q000401:mortality; D013297:Streptococcus pyogenes / Q000145:classification* / Q000302:isolation & purification / Q000472:pathogenicity; D014481:United States / Q000453:epidemiology