Norovirus, the highly contagious stomach bug that causes vomiting and diarrhea, is spiking across the US. What to know about symptoms and prevention.

STATEN ISLAND, N.Y. — Norovirus, also known as the stomach flu, rang in 2025 in a big way across the United States, and continues to surge. The highly contagious virus causes vomiting and diarrhea, and a record number of outbreaks have been reported for this time of year, according to recent data.

Norovirus is highly contagious and causes vomiting and diarrhea. But, in the overwhelming majority of cases, people recover with no lasting consequences.

Most norovirus outbreaks occur when people who are already infected spread the virus to others by direct means, such as through sharing food or eating utensils.

Norovirus outbreaks are common throughout the year, but prevalent from November to April. The Centers for Disease Control and Prevention (CDC) said this year's number of reported norovirus outbreaks has exceeded the numbers in the recent years before the COVID-19 pandemic.

The number of cases of a wretched stomach bug are up in parts of the US this winter, according to government data. Here's what to know.

Cases of norovirus, a highly contagious stomach bug, are surging in parts of the United States this winter, according to government data.

Cases of norovirus are surging in the United States. It’s the country’s leading cause of foodborne illnesses but there have been even more outbreaks than usual recently — hitting schools, holiday gatherings and cruise ships.

LANDSTUHL, Germany - Cases of norovirus, a wretched and highly contagious stomach bug, are surging in parts of the United States and Europe this

The United States is seeing a dramatic increase in norovirus cases, with reported outbreaks reaching their highest numbers since 2012. According to the U.S. Centers for Disease Control and Prevention (CDC), there were 91 outbreaks during the week of December 5, surpassing prior records for this time of year.

Health experts told Newsweek about the threats posed by the viruses and shared the best ways to protect oneself.

Norovirus is a very contagious virus causing vomiting and diarrhea. It's not related to the flu despite being commonly referred to as 'stomach flu.'