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COVID-19: Vaccine information, visitor restrictions, testing, treatment, and additional resources
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A virus is a microscopic organism that causes infection and disease. Viral illnesses can range from mild to severe. Some examples are the common cold, West Nile virus, polio, and smallpox.
Current as of: February 9, 2022
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Adam Husney MD - Family Medicine & Elizabeth T. Russo MD - Internal Medicine
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