COVID-19 Pandemic Saw Rise in Pediatric Invasive Group A Streptococcal Infections

The incidence of invasive Group A streptococcal (GAS) infection was found to increase among pediatric patients during the COVID-19 pandemic and coincided with an outbreak of respiratory viruses, according to results of brief report published in Open Forum Infectious Diseases. 

Researchers conducted an interrupted, retrospective, time-series analysis using data from the Robert Debré University Hospital in Paris, France. Data were captured from pediatric patients diagnosed with culture- or polymerase chain reaction-confirmed invasive GAS infection between January 2009 and December 2022. The primary outcome was the 3-month rate of invasive GAS infections per 1000 hospital admissions, which was assessed over 3 study periods based on the implementation of nonpharmaceutical interventions (NPIs) in response to the COVID-19 pandemic. The 3 study periods included the pre-NPI period (January 2008-March 2020), the NPI period (April 2020-April 2021), and the NPI relaxing period (May 2021-December 2022).

Secondary outcomes were the clinical and microbiologic profiles of invasive GAS infection during each period, analyzed via Mann-Whitney U, chi-square, and Fisher exact testing. The incidence of invasive GAS infection was analyzed with a quasi-Poisson regression model. 

A total of 135 patients were included in the analysis, of whom the median age was 3 (IQR, 1-6) years, and 50% were younger men or boys.

The 3-month rate of invasive GAS infection per 1000 hospital admissions remained stable during the pre-NPI period but was found to significantly decrease (odds ratio [OR], 0.30; 95% CI, 0.10-0.49; P = .006) in the NPI period. During the NPI relaxing period, the 3-month rate of invasive GAS infection increased significantly, peaking in the last quarter of 2022 (OR, 6.8; 95% CI, 4.7-8.5; P <.001).

Further analysis of the last quarter of 2022 showed that the peak in invasive GAS infection incidence was associated with increased circulation of respiratory viruses, particularly influenza. 

Of patients diagnosed with invasive GAS infection during the pre-NPI period, the majority had osteoarticular infections (38.6%), followed by bacteremia (33.3%), pleural empyema (14.9%), and skin infections (6.1%). During the NPI-relaxing period, the rate of pleural empyema increased to 33.3% (χ², P = .04; Fisher exact, P = .06).

The rate of pediatric intensive care unit admissions (P = .29) and mortality (P = 1.0) were similar between the study periods. Factors related to virulence and the distribution of emm-types also were similar between the study periods. 

Limitations of this study include its lack of randomization and its retrospective single-center design. In addition, invasive GAS strains were not evaluated via whole-genome sequencing.

According to the researchers, “[T]hese findings suggest that respiratory virus dynamics may have played a role in the recent changes in [invasive] GAS epidemiology.”

This article originally appeared on Infectious Disease Advisor