Norovirus, a highly contagious stomach bug, is rapidly spreading across parts of the United States this winter, Government data has revealed. The U.S. Centers for Disease Control and Prevention (CDC) reported 91 infections during the first week of December, a sharp increase from 69 outbreaks recorded in the last week of November. This figure represents more than double the highest weekly count recorded over the past three years.
According to CBS News, norovirus infections often referred to as stomach flu, typically cause sudden vomiting and diarrhoea with outbreaks common in crowded settings such as cruise ships, nursing homes, jails, schools, and other close-contact environments.
This month, hundreds of passengers across three cruise ships fell ill, contributing to 14 cruise-related norovirus outbreaks this year, the highest monthly total recorded in 2024.
On land, cases are also increasing. The Minnesota Department of Health recently reported 40 cases, which is double the average for December, according to CBS News Minnesota.
According to the CDC, norovirus is responsible for 58% of foodborne illnesses in the US, with outbreaks commonly occurring in schools, healthcare facilities, and restaurants.
No Cure Yet
There is no medication to treat norovirus yet. However, staying hydrated is vital, and medical attention should be sought for severe dehydration, particularly in children.
Unlike SARS-CoV-2, the virus responsible for Covid-19, norovirus is a non-enveloped virus. Its tough protein shell, or capsid, makes it resistant to pH and temperature changes, as well as many disinfectants, including alcohol-based hand rubs or sanitisers.
Alcohol sanitisers, regardless of their concentration, cannot penetrate the capsid to deactivate the virus.
In contrast, enveloped viruses like SARS-CoV-2 have a fragile outer layer that alcohol can break down easily. This key difference has caused confusion, especially since alcohol sanitisers became a hygiene staple during the Covid-19 pandemic.
Preventative Measures
Frequent handwashing with soap and warm water for 20 seconds, avoiding food preparation when symptomatic, and disinfecting surfaces are crucial to preventing the spread of the virus.
While alcohol-based sanitisers remain effective against many respiratory viruses, they are not a reliable defense against norovirus.
Health experts recommend using alternative disinfectants, such as hypochlorous acid-based sanitisers, alongside proper handwashing with soap and water. Despite these findings, many healthcare facilities continue to rely heavily on alcohol-based sanitisers, partly due to their convenience.
