The Infectious Diseases Society of America (IDSA) does not recommend testing for strep throat in most children younger than 3 years old because strep infection is uncommon, there is not a classic symptom presentation, and severe sequelae are rare.1 In this study, we examined patterns in testing and treating strep throat among pediatric patients and the impact of treatment on adverse outcomes.
While symptomatic children younger than 3 years are tested for strep throat less often than older children, testing in younger children is not uncommon, as seen in Figure 1. In 2024 so far, those under 1 year of age are tested during 2.7% of visits for upper respiratory symptoms, while those aged 6 to 9 had a testing rate of 29.4%. We saw similar rates of testing for strep in these age groups in all years since 2017.
Of patients who were tested for strep throat, younger children tested positive less often than older children. In 2024, we found the following percentages of patients who had a positive test result: 3.9% of those under age 1, 7.4% of those 1 year of age, 9.9% of those 2 years of age, 12.9% of those aged 3 to 5, and 16.4% of those aged 6 to 8, as seen in Figure 2.
Despite the variation in positivity rates, when children had a positive strep test or a strep diagnosis, the treatment rate was high (>90%) among all age groups, including those younger than 3 years. Those under 1 year old had the lowest treatment rate at 90.6%, while age groups older than 2 years had treatment rates around 94%.
To understand the risks from having strep throat among children, we studied the likelihood of all-cause hospital admissions between 1 and 60 days after a positive strep test or diagnosis among patients who had strep throat between January 1, 2017, and April 1, 2024. Patients less than 1 year old were 304% more likely to be hospitalized than those aged 3 to 5, as seen in Figure 3. Those who were 1 year old had a 175% increased likelihood and patients aged 2 had a 58% increased likelihood. A sensitivity analysis of patients with evidence of an upper respiratory symptom yielded similar trends.
Additionally, we found that treatment with antibiotics within two days of being diagnosed or testing positive for strep reduced the likelihood of all-cause hospital admission for patients under age 3. Those who were 2 years old had a 55% reduced likelihood of being admitted, those who were 1 year old had a 33% reduced likelihood, and those less than 1 year old had a 38% reduced likelihood, as seen in Figure 4.
