- Infants and toddlers attending ten day-care facilities in closed communities in southern Israel were tested monthly for pharyngeal carriage ofStreptococcus pyogenes and associated respiratory morbidity. Overall, the prevalence ofStreptococcus pyogenes was 2.7 % in infants and 8.4 % in toddlers, reaching 8.5 % and 17.8 % in the two groups, respectively by midwinter. In 4 of 61 (6.6 %) infants and 15 of 67 (22.4 %) toddlers, the organism was recovered in more than one month (range 2 to 5 months).Streptococcus pyogenes in the pharynx was only associated with rhinitis during the spring and summer but not with other respiratory symptoms. During the study period, a mean of 0.9 strains were isolated in day-care facilities attended by infants, while a mean of 2.1 strains were found in toddlers. Young children attending day-care facilities show early acquisition ofStreptococcus pyogenes in the pharynx.