Seasonal Prevalence of Strep Throat
Strep throat is most common during winter and early spring in temperate climates, specifically from November through May. 1
Peak Season Timing
- Group A Streptococcal (GAS) pharyngitis occurs predominantly in late winter and early spring in temperate regions 2
- The specific timeframe is November through May in temperate climates 1, 3
- This seasonal pattern is consistent across multiple guidelines from the Infectious Diseases Society of America 1, 3
Geographic and Climate Variations
- The winter-spring peak applies specifically to temperate climates 1
- In contrast, streptococcal skin infections (impetigo) show a different pattern, being more common in summer and fall 4
- Respiratory streptococcal infections are more commonly isolated in winter months, while impetigo serotypes predominate in warmer seasons 4
Clinical Context for Seasonal Awareness
- During peak winter-spring months, as many as 20% of asymptomatic school-age children may be GAS carriers 1
- The seasonal pattern is particularly relevant for the 5-15 year age group, which represents the highest risk population 1, 3
- Even during peak months, the vast majority of acute pharyngitis cases remain viral in etiology and do not require antibiotics 1
Practical Implications
- Clinicians should maintain higher clinical suspicion for GAS pharyngitis during November-May 1
- The seasonal timing helps differentiate between viral pharyngitis (which can occur year-round) and bacterial streptococcal infection 1
- Understanding seasonal patterns aids in appropriate use of diagnostic testing and avoiding unnecessary antibiotic prescriptions during off-peak months 1