Wastewater Data Show Norovirus at High Levels in Much of U.S.

Wastewater surveillance shows norovirus at high levels across much of the United States, with concentrations rising in the Northeast. The Centers for Disease Control and Prevention’s NoroSTAT program recorded 1,194 outbreaks from Aug. 1 to May 7, compared with 2,534 during the same period the previous year.

Amanda Bidwell, scientific program manager at WastewaterSCAN, stated that national levels remain in the high category due to concentrations over the last 21 days. Dr. Linda Yancey, an infectious disease specialist at Memorial Hermann, said the nationwide numbers are average for this time of year, while the San Francisco Bay Area shows an outbreak.

17. 17 caused about 75 percent of outbreaks. Dr. Scott Roberts, associate medical director of infection prevention at Yale School of Medicine, noted that seasonal travel and heat may increase close contact and indoor crowding, aiding spread. Norovirus spreads through contaminated food, water, surfaces, or direct contact and causes vomiting and diarrhea that begin 12 to 48 hours after exposure.

Most healthy adults recover within several days but can remain contagious for up to two weeks.