The Centers for Disease Control and Prevention is warning of a new norovirus bug sweeping the country. Dr. David Samadi said on Sunday Housecall that this is the second most common bug in the United States, affecting over 21 million Americans and causing hundreds of deaths.

Symptoms include nausea, vomiting, diarrhea and stomach cramping. Once you catch it, you’ll see symptoms about 24 hours after and it’ll last about a week. Mostly younger people and the elderly are in danger due to dehydration.

It is difficult to prevent yourself from catching this particular bug and those who have it can remain contagious for as long as two weeks after recovery.

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Places where a lot of people are in contact, like cruises and planes, are hotbeds for this virus to spread. It’s critical to wash your hands -- lather up with soap and water for 30 seconds. For those of you who love hand sanitizer, Dr. Samadi says that just won’t cut it. “It’s a very resistant bug, it’s very contagious and it mutates very quickly year by year.”

To put in perspective how contagious it is, Dr. Marc Siegel said it takes 20 particles of the norovirus to cause illness compared to 1,000 particles of the flu. It lives on surfaces much longer than the flu. Bleach will help kill the virus on surfaces. Dr. Siegel also emphasized staying hydrated and if you’re not feeling well, do not handle food.

For more information and tips on the norovirus, watch the clip below. Also, 'like' Sunday Housecall on Facebook.

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