Seroepidemiology of the group-A streptococcal carriage state in a private pediatric practice
C. M. Ginsburg, G. H. McCracken Jr, S. D. Crow, B. R. Dildy, G. Morchower, J. B. Steinberg and K. Lancaster
During a 24-month period, throat-swab cultures were obtained on 1,362 well
children who were 3 months to 14 years of age. The overall incidence of
positive cultures for group-A beta-hemolytic Streptococcus was 3.3%; in
those children older than 1 year, it was 4.4%. The largest incidence of
positive cultures occurred in the 5- to 7-year-old (8.3%) and 8- to
10-year-old (4.5%) age groups. No positive cultures were obtained from 339
infants younger than 1 year of age. There was no relation between positive
cultures and the month of the year. There were no significant differences
between the age, sex, presence of tonsils, previous group-A streptococcal
infections, or the presence in a daycare center or school of children with
positive cultures compared with those children with negative cultures.
Follow-ups were obtained on 29 of 45 children with positive throat
cultures; all of the children were asymptomatic and had normal results of
physical examinations. Group-A streptococci of the same serotype as the
original isolate were isolated from 19 of these children. Three to four
days after a ten-day course of erythromycin estolate, five of 19 children
again had positive cultures. Twenty-six of the 29 children had a total of
43 siblings residing in the home. Serotypically identical group-A
streptococci were isolated from five siblings (11%). Only one of 29
patients from whom paired serum samples were obtained showed a fourfold
rise or fall in the Streptozyme titers.
