Group A Streptococcal infections are neglected public health problem. Therefore, molecular epidemiology of GAS was explored in Chandigarh, India where surveillance for GAS infections was conducted in the schools.
A total 7004 school children (3903 boys and 3101 girls), in the age group of 5-15 years, were clinically examined from the eight government schools of Chandigarh (India). Pharyngeal swabs were taken from all the students whereas skin swabs were taken only from children having skin lesions. All the swabs were streaked on blood agar plates. GAS strains were identified and emm typed by PCR and sequencing.
Out of the 7004 throat swabs, 86 GAS were isolated. The prevalence of GAS was found to be 1.4% (22/1572) among children having pharyngitis and 1.2% (64/5432) among those who did not have pharyngitis. Among 124 children with skin lesions, 24 GAS were identified. The prevalence of GAS in skin lesions was 19.4%. Out of 110 GAS identified from 7128 swabs during the study, 35 different emm types were identified; emm12 was most prevalent.
High heterogeneity observed in emm type pattern of GAS in North India which is a big challenge for future vaccine development studies.