CDC Data Reveals Norovirus Outbreak in the Northeastern Region

The highly contagious norovirus, which causes vomiting and diarrhea, has seen a substantial increase in cases in the Northeast United States over recent weeks, reference data from the Centers for Disease Control and Prevention (CDC).

Surveillance data indicates that there has been a nationwide increase in positive norovirus test results—a common trend for the virus during winter months. However, the northeastern states have experienced it the most with a 13.4% average over three weeks for positive tests. The ratio of positive tests has been above 10% since December 2023.

Other regions in the U.S. have also observed an increase in norovirus cases, although at a lower rate. In southern states, the positive test rate for the last three weeks is around 9.5%, in the Midwest, it is 10%, and in the western states, it is 12%.

This article provides an overview of the norovirus, details the spike in cases in the Northeast, and offers preventative measures.

The current surge in norovirus outbreak, while alarming, is typical for this period of the year, per Thomas Russo, MD, professor and chief of infectious disease at the University at Buffalo. He explains that norovirus can occur year-round but is more common in the colder season. “Norovirus typically surfaces between November to April and peaks in January,” states Russo.

Norovirus has a high level of contagiousness. Just a small quantity of particles—below 100—are needed to infect a person. To put it into perspective, a person with norovirus can shed billions of virus particles in their stool and vomit.

Increased social interaction during the winter months, often in close quarters equals within frequent contact with infected individuals and the virus's contagiousness attribute to spike in cases. Amesh A. Adalja, MD, senior scholar at the Johns Hopkins Center for Health Security, states, “Any form of social interaction exposes you to individuals with the virus.”

The main mode of norovirus transmission is by making direct contact with an infected individual, consuming contaminated food or beverages, touching surfaces infected with norovirus particles and then touching the face or mouth, or sharing cups or utensils with a person having the virus.

Despite the ubiquitous presence of the norovirus currently, Russo optimistically acknowledges that it might not stay predominant for much longer.

Shaffner hypothesizes that a rise in temperatures across the U.S. with the arrival of spring might help in curbing the spread of the virus. He states, "As the rest of the country warms up, we hope that the virus will be limited to the Northeast."

Practicing proper hygiene is recommended as the best defense against the norovirus. Adalja advises, “Wash your hands thoroughly.” (Hand sanitizers are not effective against norovirus.) He also suggests avoiding dining in restaurants when the rate of cases is high in the area since food service employees commonly pass on the virus.

If a household member has contracted norovirus, it's crucial to clean the infected surfaces using a bleach solution, William Schaffner, MD, an infectious disease specialist and professor at the Vanderbilt University School of Medicine, suggests. Regularly touched objects, such as door handles and remote controls, should also be kept sanitized.

Russo recommends the use of masks and gloves while taking care of a sick person since droplets and particles from a vomiting event can spread the virus, although this is not an official recommendation.

There isn't a specific treatment for norovirus, but hydration is vital. Russo recommends taking small sips of water or sports drinks. Dehydration can occur due to loss of fluids from vomiting and diarrhea, which could necessitate the need for intravenous (IV) fluids.

Sick individuals should diligently wash their hands as the virus can be transmitted for up to two weeks even after recovery. Individuals recovered from norovirus should also avoid close interactions with others such as preparing food or offering healthcare for at least 48 hours after symptom cessation.

Most norovirus patients recover swiftly, barring a few 'days of misery,' as Schaffner puts it, it can be severe or deadly for very young children or the elderly. The situation is also stressful for emetophobia - (an extreme fear of vomiting) sufferers who face significant distress at the prospect of vomiting or being near someone who vomits.