FOLLOWING revised national guidance on post-exposure prophylaxis, England observed a marked decrease in invasive Group A Streptococcus (iGAS) infections among young children.
In response to a sharp rise in paediatric iGAS cases in late 2022, the UK Health Security Agency (UKHSA) extended its antibiotic prophylaxis recommendations in January 2023. The new guidance advised that all household contacts aged <10 years of a confirmed paediatric iGAS case receive a 10-day course of antibiotics, regardless of symptoms. Researchers evaluated national surveillance data comparing the 6 months before and after implementation.
Between July–December 2022, 141 iGAS cases were reported in children under 10 years. This fell to 32 cases between January–June 2023, a 77% reduction (incidence rate ratio [IRR]: 0.23, 95% CI: 0.15–0.35). Among children aged ≥10 years, the incidence remained stable (IRR: 1.10, 95% CI: 0.57–2.12), suggesting the decline was limited to the prophylaxis target group. Based on case estimates and national antibiotic dispensing figures, the number needed to treat to prevent one case of paediatric iGAS was calculated at 200.
This is the first real-world evidence that expanded prophylactic antibiotic use can reduce community transmission of iGAS. The findings may inform global public health responses during future surges.
Reference
De Gier B et al. Household secondary invasive group a streptococcal infections before and after a prophylaxis guideline change, the Netherlands, 2022-2024. Abstract 2394. ESPID Annual Meeting, 26-30 May, 2025.
