The number of positive cases of the norovirus, a highly transmissible gastrointestinal illness also known as the stomach flu, is rising across the United States.
There were 225 norovirus outbreaks reported to the CDC between Aug. 1, 2022, and Jan. 8, 2023, compared to 172 outbreaks during the same period the previous season, according to CDC data.
The highest rate of positive tests is in the Midwest.
“While norovirus cases are rising in the U.S., CDC data as recent as January 2023 show that reported norovirus outbreaks are within the expected range for this time of year,” CDC spokesperson Kate Grusich said, according to NBC News.
“Prevention measures implemented during the COVID-19 pandemic were likely effective in preventing norovirus outbreaks. As pandemic restrictions have relaxed, the number of norovirus outbreaks has returned to levels similar to pre-pandemic years.”
Though it’s called the stomach flu, norovirus is not related to influenza. Symptoms of norovirus include diarrhea, vomiting, nausea, stomach pain, fever, and body aches.
There’s no treatment for norovirus, but doctors usually recommend people drink plenty of fluids.
In England, norovirus rates are 66% higher than the average over the five seasons before the COVID pandemic, data from the UK Health Security Agency shows.The biggest rise in positive cases is in people 65 and older.
CDC: “Norovirus National Trends.”
NBC News: “Norovirus appears to be spreading as rate of positive tests spikes.”
UK Health Security Agency: “National norovirus and rotavirus report, week 6 report: data up to week 4 (29 January 2023).”