A new strain of norovirus may be circulating, potentially leaving fewer people with immunity, according to Lynn Roberts, an epidemiologist with the Wisconsin Department of Health Services.
Newsweek has reached out to the U.S. Centers for Disease Control and Prevention (CDC), Roberts, and several infectious disease experts for comment and confirmation via email on Saturday morning.
Why It Matters
New strains of viruses are not uncommon, typically arising from mutations or genetic recombination. They can lead to larger outbreaks due to less widespread immunity. The CDC notes that immunity to norovirus after infection is short-term, lasting from a few months to about a year, on average.
The highly contagious illness has reached its highest levels for this time of year in more than a decade, according to the latest CDC data. The CDC has reported 91 outbreaks during the week of December 5, up from an average of 65 during the same period from 2012 to 2020.
Norovirus Outbreaks: Public Health Official Warns of Risk From New Strain
