Stomach flu is an intestinal infection caused by several different viruses that can result in diarrhea
and vomiting. A highly contagious condition, the stomach flu is the second most common illness in the United States. It causes millions of cases of diarrhea each year.
But the so-called "stomach flu" is actually not stomach flu at all. Viruses that cause it affect the small intestine, not the stomach. Furthermore, stomach flu viruses are not flu viruses. The flu virus
is the influenza virus
, which affects the respiratory system. The influenza
virus does not affect the intestines.
Regardless of the inaccuracies of the term "stomach flu," it is the most commonly used term to describe what healthcare providers call viral gastroenteritis.
Anyone can get the stomach flu. It occurs in people of all ages and backgrounds.
Outbreaks can occur in institutional settings, such as schools, childcare facilities, and nursing homes, and it can occur in other group settings, such as banquet halls, cruise ships, dormitories, and campgrounds.
Many different viruses can cause this illness. Some common types of stomach flu viruses include:
Each virus has its own seasonal activity. For example, in the United States, rotavirus and astrovirus infections occur during the cooler months of the year (October to April), whereas adenovirus infections occur throughout the year.