Norovirus Worldwide

Global Trends

Worldwide, about one out of every five cases of acute gastroenteritis (diarrhea and vomiting illness) is caused by norovirus. Globally, norovirus is estimated to be the most common cause of acute gastroenteritis. It is responsible for 685 million cases every year, 200 million of these cases are among children younger than 5 years old. This leads to an estimated 50,000 child deaths every year, nearly all of which occur in developing countries.

Norovirus

The Global Burden of Norovirus & Prospects for Vaccine Development

This PLOS norovirus collection fills critical knowledge gaps and provides key information for the development of a much-needed vaccine. This is a “living collection” and more articles will be added over time.

New Report Available

Global Burden of Norovirus and Prospects for Vaccine Development [4.39 MB, 46 pages] brings together the work of norovirus researchers from around the world to describe the burden of norovirus globally and outline further research needed to fill gaps in knowledge in order to make norovirus vaccines a reality.

The WHO Foodborne Disease Burden Epidemiology Reference Group (FERG) recently issues a comprehensive report estimating the global burden of foodborne diseases. Norovirus ranks as

#1 cause of foodborne illness
#4 cause of foodborne deaths
#5 cause of foodborne DALYs

Though most deaths occur in developing countries, norovirus is a problem in both low and high income countries. Every year norovirus is estimated to cost $60 billion, these costs are mainly due to healthcare costs (money spent to treat complications from norovirus) and lost productivity (people not being able to work because they are sick).

Due to the increasing use of rotavirus vaccine, norovirus is the most common cause of acute gastroenteritis for which children need medical care in some countries, including the United States and Nicaragua. This trend is likely to continue as other countries see the benefits of rotavirus vaccination.

Norovirus infections and outbreaks are usually more common in cooler, winter months. About half of all cases occur from December through February in countries above the equator (center line of the earth) and June through August in countries below the equator. However, in places closer to the equator, norovirus may be less seasonal. This may be because of temperature or the timing of the rainy season, but may also be related to when and how many babies are born.

Outbreaks

Worldwide, norovirus is the leading cause of gastroenteritis outbreaks. The most common norovirus strain (genogroup II genotype 4) is a major cause of outbreaks worldwide. New norovirus strains emerge about every 2 to 4 years. Often, but not always, these new strains lead to an increase in outbreaks worldwide.

The CDC’s Division of Viral Diseases works with many global partners to identify the burden of acute gastroenteritis caused by norovirus and to prevent norovirus outbreaks throughout the world.