Coronavirus: a type of common virus that infects humans, typically leading to an upper respiratory infection (URI.) Seven different types of human coronavirus have been identified. Most people will be infected with at least one type of coronavirus in their lifetime. The viruses are spread through the air by coughing and sneezing, close personal contact, touching an object or surface contaminated with the virus and rarely, by fecal contamination. The illness caused by most coronaviruses usually lasts a short time and is characterized by runny nose, sore throat, feeling unwell, cough, and fever.
Examples of human coronaviruses that have been reported to cause severe symptoms include the MERS-CoV (the beta coronavirus that causes Middle East Respiratory Syndrome, or MERS), SARS-CoV (the beta coronavirus that causes severe acute respiratory syndrome, or SARS, and the new 2019 Novel Coronavirus (2019-nCoV) outbreak that began in Wuhan, China.
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<https://www.cdc.gov/coronavirus/about/symptoms.html>