2024 Was Bad Year for Norovirus on Cruise Ships

Data from the U.S. Centers for Disease Control and Prevention (CDC) indicates that 2024 was the worst year for cruise ship-based gastrointestinal outbreaks in more than 10 years, with a total of 16 outbreaks recorded.

According to a CNN article, the CDC data also indicated that the majority of gastro outbreaks at sea in 2024 were associated with norovirus.

The 16 outbreaks was the largest number reported in more than 10 years. Just in December, five ships reported significant outbreaks (meaning 3% or more of the ship’s passengers and crew reported to the medical staff with gastrointestinal symptoms).

In 2023, 14 outbreaks were recorded, while 2020-2022 saw significantly fewer outbreaks recorded as the industry was shut down or still recovering. In 2019, the last full year of sailing before the pandemic, there were 10 reported outbreaks, according to the CDC.

Cruise ships were not alone in having higher than normal norovirus outbreaks in 2024. At the end of December, CBS News reported that cases of norovirus were surging in parts of the U.S. The article cited CDC data showing nearly a 32% increase in reports of norovirus outbreaks from the last week of November into the first week of December. Year-over-year, the increase was 40%.

Norovirus, and gastrointestinal outbreaks in general, are more common during the winter months, so continued cases at sea and on land are likely. The best defense against norovirus is frequent hand washing.