Close gatherings over the Thanksgiving holiday could cause an uptick in emergency room visits in Pennsylvania due to a trio of respiratory illnesses that typically rise this time of year, as well as a new mutation of the common flu that doesn’t respond to this year’s flu shot.
Pennsylvania emergency rooms typically see an increase in COVID-19, influenza, and RSV rates during the holidays. This year’s flu season could be more serious due to a new Influenza H3N2 mutation known as “subclade K,” which is spreading in North America, including the United States.
Although the current flu vaccine offers protection against the H3N2 strain, it doesn’t cover subclade K, which hadn’t been identified when the vaccine was developed. The variant has mutated seven times, making H3N2 an even more serious threat, according to experts.
“Knowing that there’s a new mutated strain out there and H3N2 generally causes more severe disease is concerning,” Dr. Robert Hopkins Jr., medical director of the National Foundation for Infectious Diseases, told NBC’s “Today” show.
The symptoms of the new strain are similar to those caused by common influenza, including fever, chills, body aches, headaches, extreme fatigue, congestion or runny nose, and coughing.
The symptoms come on suddenly. “It’s that hit-by-a-truck feeling,” Hopkins told “Today.”
This particular mutation is now dominant in many countries, including Japan, the United Kingdom and Canada, Forbes reported.
The CDC currently lists Influenza A H3N2 as the cause of most flu cases in the United States. The extent of the spread of the subclade K mutation in the United States because the Centers for Disease Control and Prevention didn’t do any tracking for its FluView report during the recent government shutdown.
The Pennsylvania Department of State has not yet released any data or information on subclade K. The latest data from the CDC updated Nov. 19 shows that acute respiratory illness rates overall are “low” in Pennsylvania.
Cases of all three viruses are trending up the with the colder months, but those rates are low across all ages, including more vulnerable groups like infants and toddlers. Over the week with the most recently available data in early to mid-November, the state has 112 new hospital admissions for the flu, 39 for RSV, and 242 for COVID-19.
These numbers are slightly lower than the past two years, which have marked a drastic drop off from the heights of illness spreading from 2020 though 2023.
The state has also continued to press on the importance of vaccines, however, despite the low numbers.
Nationwide, acute respiratory illnesses remain at low or very low levels, according to the CDC; however, emergency room visits for RSV are increasing in many states in the South and Southeast. COVID-19 activity remains low, and seasonal flu activity is low nationally but increasing, according to the surveillance report.
Wastewater surveillance reports from 33 monitoring sites, updated on Nov. 20, showed “very low” COVID, flu, and RSV rates.