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2 cases of norovirus confirmed at Yosemite National Park, officials say

Approximately 170 people have come down with gastrointestinal illness, officials at Yosemite National Park announced Thursday. They say those affected include park visitors and employees who spent time at Yosemite Valley. There are also two confirmed cases of the highly-contagious norovirus.

"Most of the cases occurred on and around the first week of January 2020 and there has been significant decline of new cases reported over the past several days," according to park officials. "Yosemite National Park officials and medical professionals with the National Park Service Office of Public Health (OPH) are continuing to investigate the circumstances surrounding the illness and are continuing to conduct interviews with affected people. The overwhelming majority of the reported cases are consistent with norovirus."

Officials said they are working to prevent additional illnesses and Yosemite National Park "continues to undertake extensive cleaning and enhanced sanitation protocols," according to the statement. Anyone who has visited the park and feels ill can send officials an email.

What is norovirus?

Norovirus, sometimes called the stomach flu (though it is not related to the flu virus), is a very contagious virus that causes vomiting and diarrhea. Other symptoms can include nausea, stomach pain, fever, headache, and body aches. 

A person usually develops symptoms 12 to 48 hours after being exposed to the virus. People of all ages can be affected by norovirus.

How is norovirus spread?

"When you are sick with norovirus, you can shed billions of virus particles in your vomit and poop. It only takes a few of these particles to make someone sick," according to the Centers for Disease Control and Prevention. 

The illness spreads rapidly if you eat food or drink liquids that are contaminated with the virus, touch contaminated surfaces or objects and then touch your mouth, or have direct contact with an infected person, such as by caring for them or sharing food or utensils with them.

The CDC notes that while people often associate cruise ships with norovirus, acute gastrointestinal illness is relatively infrequent on cruise ships. However, the close living quarters on the ship increases the risk of transmission.

Norovirus spreads very easily, including through direct contact with an infected person, touching a surface or object contaminated with norovirus, or eating food or drinking liquids contaminated with norovirus. Symptoms of norovirus usually begin 12-48 hours after exposure.

How is norovirus treated?

Most people will recover from norovirus in a couple of days. Since norovirus is a virus and not bacteria, antibiotics will not treat the infection.

If you are sick from norovirus, drink plenty of liquids to replace fluid lost from vomiting and diarrhea. This will help prevent dehydration.

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