Related Experiment Videos
Seroepidemiology of the group-A streptococcal carriage state in a private pediatric practice
Insights
Group-A Streptococcus (GAS) is common in well children over one year old, particularly those aged 5-10. Eradicating GAS with erythromycin is often ineffective, with high recurrence rates and sibling transmission observed.
Area of Science:
- Pediatrics
- Infectious Diseases
- Microbiology
Background:
- Group-A beta-hemolytic Streptococcus (GAS) is a significant pathogen in pediatric populations.
- Understanding the epidemiology and carriage of GAS in well children is crucial for infection control.
Purpose of the Study:
- To determine the incidence of GAS pharyngeal carriage in a cohort of well children.
- To investigate factors associated with GAS carriage and the effectiveness of treatment.
Main Methods:
- Throat-swab cultures were collected from 1,362 children aged 3 months to 14 years over 24 months.
- Follow-up cultures and sibling surveillance were performed on a subset of positive cases.
- Erythromycin estolate treatment was evaluated in children with persistent positive cultures.
Main Results:
- Overall GAS incidence was 3.3%, rising to 4.4% in children over one year old.
- Highest incidence occurred in the 5-7 (8.3%) and 8-10 (4.5%) age groups; no carriage was found in infants under 1 year.
- Erythromycin treatment showed limited efficacy, with 5 of 19 children remaining culture-positive post-treatment. Eleven percent of siblings were also colonized.
Conclusions:
- GAS pharyngeal carriage is prevalent in school-aged children.
- Standard erythromycin treatment appears insufficient for eradicating GAS carriage, suggesting potential for reinfection or persistent carriage.
- Household transmission among siblings is a notable factor in GAS epidemiology.
Abstract:
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.