The burden of group A streptococcal pharyngitis in Melbourne families.

Results: Cohort retention was 97 per cent. The spring, summer and winter carriage rates for children were 13.0, 8.0 and 16.0 per cent respectively. The incidence of GAS pharyngitis was 14 per 100 personyears for children. For every primary case there were 0.7 secondary cases and 24 per cent of families experienced at least one episode of GAS pharyngitis per year. Preliminary costing data suggest that 46 per cent of cases lead to school absenteeism and a high rate of antibiotic use. Interpretation & conclusion: The present data suggest that GAS pharyngitis remains very common in childhood, and that it has further implications in terms of secondary cases and costs.