Dr. Handy’s Corner: Let’s Talk about Group A Strep

This month’s video focuses on group A Streptococcus (group A strep), a bacterium that causes several different illnesses in children, including strep throat, scarlet fever and skin infections. It can also cause more invasive infections, like bloodstream infections, bone infections and necrotizing fasciitis (more commonly referred to as “flesh-eating bacteria”). Recently, the Centers for Disease Control and Prevention (CDC) announced the results of an investigation into a spike in these more invasive, and more scary, outcomes of group A strep infections.

Two points in the video are important to remember in understanding what the CDC found. First, group A strep is passed from one person to another through respiratory secretions. Second, other respiratory infections can provide an opportunity for group A strep infections to become invasive, increasing the risk in individuals sick with a primary viral infection.

The CDC investigation of data from two surveillance sites found that between October and December 2022, 34 cases of invasive group A strep were reported. In comparison between 2016-2019, those same two sites averaged 11 cases between October and December of each year.

While this finding might seem alarming, parents should realize that:

• The rise was situational. COVID-19 pandemic measures, including masking and distancing, led to a historic decline in group A strep infections among all age groups. Accordingly, as we returned to pre-pandemic activities, a resurgence could be anticipated, particularly as rates of common respiratory viruses rebounded. 
• Group A strep is known to seize opportunity. The reported rise in cases of invasive group A strep coincided with a rise in hospitalizations for respiratory viruses, such as RSV and influenza. Almost half of the children had an identified viral infection that likely predisposed them to this secondary infection. As described in the video, viruses can break down the lining of the pharynx and allow bacteria, such as group A strep, to enter the bloodstream. They also can briefly modify how a person’s immune system functions, allowing these types of bacteria to more easily evade the immune system.
• Most group A strep infections will not be invasive. Even when this bacterium takes advantage of another respiratory infection, in most cases a severe outcome requiring hospitalization will not be the result. If your child has a respiratory infection, seems to be recovering and then starts to get ill again, think about these opportunity-seeking bacteria and check with your child’s healthcare provider whether they might need to be seen or receive an antibiotic.
• Recognize that some of the viruses that predispose a child to invasive group A strep are vaccine preventable. By ensuring that your child gets routinely recommended vaccines, like chickenpox and influenza vaccines, you can decrease their risk of these infections while also decreasing their chance of secondary bacterial infections, like group A strep. And with RSV vaccines on the horizon, parents will soon have another opportunity to protect their children.

To see the full summary of the CDC investigation, check the March 10 Morbidity and Mortality Weekly Report (MMWR).