Impact of the SARS-CoV-2 Pandemic on the Epidemiology of Streptococcus pyogenes: A Five-Year Retrospective Study

Abstract

The SARS-CoV-2 pandemic significantly affected the epidemiology of Streptococcus pyogenes, a pathogen associated with various clinical presentations such as pharyngitis, scarlet fever, and invasive diseases. This study analyzed the incidence and characteristics of S. pyogenes infections between 2018 and 2023, examining 915 cases categorized as either respiratory or non-respiratory. Respiratory infections predominantly affected children, accounting for 76% of cases, with a median age of 5 [3, 8] years, while non-respiratory infections were more common in adults, with a median age of 46.5 [34, 64] years. Invasive respiratory infections, such as pneumonia and empyema, were more frequent in children (54.8%), whereas invasive non-respiratory infections, such as primarily cellulitis, were predominantly seen in adults (90.5%). A sharp decline in S. pyogenes infections was observed during the pandemic, with respiratory cases decreasing tenfold in 2020 compared to the previous year, and non-respiratory cases experiencing a twofold reduction. However, infection rates returned to pre-pandemic levels by 2022 and 2023, with a notable resurgence of invasive respiratory infections in children following a public health alert in the United Kingdom in late 2022. These findings highlight distinct infection patterns between pediatric and adult populations and emphasize the significant impact of the pandemic on respiratory infections, particularly in children.