Norovirus -- the highly contagious, illness-causing virus often called the stomach flu -- is spreading across Massachusetts and the nation.
Contrary to its nickname, norovirus is not related to the influenza virus. It typically causes gastrointestinal symptoms like diarrhea, vomiting, nausea and stomach pain. Mild fever and aches are possible, too. Positives tests are at a season high in the U.S., data from the Centers for Disease Control and Prevention shows.
Top Boston doctors explained to NBC10 Boston this week how you can protect yourself, how changes in human behavior related to COVID-19 have interrupted natural virus cycles and the heightened societal interest in infectious disease epidemiology.
Chief of Infectious Disease Dr. Daniel Kuritzkes said he had not heard of any cases in patients hospitalized at Brigham and Women's Hospital, but added that it’s very rare for someone to be hospitalized for norovirus.
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"The recent norovirus cases are probably another example of seeing re-emergence of common infections as we continue to emerge from our COVID-19 shells (sorry, couldn’t avoid the pun!)" Kuritzkes wrote in an email Monday. "There were periodic localized outbreaks of norovirus infection all the time pre-COVID, so not surprising that we’re seeing them again."
Dr. Shira Doron of Tufts Medical Center explained that communicable diseases come back after a period of time like the pandemic, when all infection levels were low due to social distancing and travel restrictions.
"In many cases, these curves are returning to pre-pandemic shapes and sizes, sometimes early, but not necessarily worse," Doron said. "Headlines tend to overstate the situation."
Both Doron and Boston Medical Center's Dr. Benjamin Linas noted that the virus could be getting more attention than it might have pre-pandemic due to heightened health awareness.
"I think it is also interesting that the public has become gripped by infectious disease epidemiology," Linas said. "We see surges and waning of GI and URI viruses all the time, but no one other than the ID people really cared or noticed before."
The key to protecting yourself, according to local experts, is to maintain proper personal hygiene and regular hand washing. It's also essential for food handlers to stay home from work when feeling ill, according to Kuritzkes.
"People who are ill should not prepare food for their households, although strict isolation as for COVID-19 is not necessary so long as good hygiene is practiced," Kuritzkes said.
"I think it is always wise to be aware and to use basic hygiene, but I do not think that this rise in noro cases implies anything like the 'next pandemic' or a larger problem," Linas said.