Invasive Group A Strep infections See Resurgence in England

A new study reports a resurgence of invasive group A streptococci (iGAS) infections in the country. Investigators say this disturbing trend came after there was a lifting of public health restrictions in the United Kingdom in February of last year.

Investigators are presenting this research at the ongoing European Congress of Clinical Microbiology and Infectious Diseases (ECCMID)  with a poster, "Post-pandemic surge in group A streptococcal infections in children in England."

Study Results
Investigators noted that prepandemic, a mean of 347 iGAS cases (range 301-416) per year were recorded, with 119 cases in January-March 2020. After COVID-19 infection prevention measures were added, only 44 cases were seen for the rest of 2020 (April-December) and just 29 cases in all of 2021.

After pandemic restrictions were removed in February of 2022, cases steadily rose including an increase in summer with 154 cases in June and July of last year. And, 268 cases were reported during November and December. The investigators said a total of 690 iGAS cases were recorded in 2022.

"In 2022, 60 deaths (all-cause <7d iGAS diagnosis) were reported (case-fatality rate (CFR) 9.2%), 45% (n=27) occurring during November-December, compared to 20-28 per-year pre-pandemic and 4 in 2021. Respiratory virus co-infections were identified in 19% of cases during 2022 (CFR: 19.8%)," the investigators wrote.

“iGAS presentations showed a marked rebound in 2022, particularly in children and in more affluent populations, potentially reflecting reduced exposure during the pandemic,” the investigators wrote in their study.

Trends in scarlet fever diagnoses followed a similar pattern, with 54,630 notified in 2022 in England and Wales, which are the highest totals since 1953.

Incidence In the United States
CDC tracks invasive group A strep infections through its Active Bacterial Core surveillance (ABCs), a population-based, active- and laboratory-based surveillance system. This means local and state health departments routinely contact laboratories to identify all cases, then report those cases to CDC.

Cases increased in reports looking at two states’ ABC sites. “During October 1–December 31, 2022, a combined total of 34 cases was reported in the Colorado and Minnesota ABCs sites,” the CDC reported in a MMWR. “In comparison, a 3-month average of 11 cases and four cases were observed during the same period in 2016–2019 and 2020–2021, respectively.”

Preliminary 2023 data from CDC shows that iGAS infections have remained high in children in some areas of the country even after respiratory viruses decreased in those areas.

In addition, the CDC also reports that this is happening during the time when group A strep infections are normally highest (December through April). Some areas of the country have also seen an increase in iGAS infections in adults, particularly in those aged 65 years or older.

According to the CDC’s website, the federal agency estimated that, “in the most recent five years, approximately 14,000 to 25,000 cases of invasive group A strep disease occur each year in the United States. In the last five years between 1500 and 2300 people die annually due to invasive group A strep disease.”

Preventing Spread
Public health officials remind families that good hand and respiratory hygiene are important for stopping the spread of many germs.

“Stay home when you are sick and practice good hand hygiene—regularly wash your hands with soap and water for at least 20 seconds or use an alcohol-based hand sanitizer with at least 60% alcohol and avoid touching your face. Call your child’s doctor if they are experiencing new or worsening symptoms of an illness,” Rachel Herlihy, MD MPH, state epidemiologist, the Colorado Department of Public Health and Environment, said in a statement back in December.