Coronavirus (CoV) is a family of viruses that can cause respiratory infection. The illness caused by coronaviruses in humans can range from the mild common cold to more severe disease like Middle East respiratory syndrome (MERS), which can be fatal. Most recently, a new coronavirus has been linked to a SARS-like illness that started in Wuhan, Hubei Province, China, and efforts are being taken to try and limit its spread.
What Causes Coronavirus Infection?
Common human coronaviruses are contagious, and they are easily spread from person to person. They are spread through close contact with someone who is infected via secretions from coughing and sneezing or touching objects that have the virus on them. In the United States, these coronaviruses are most likely to circulate during the fall and winter months.
Some coronaviruses are known to occur only in animals. Rarely, a coronavirus that infects animals can evolve and infect people, and then start to spread from person to person. Such an infection that spreads from animals to people is called zoonotic. Because humans have not built up any immunity to these new viruses, the illness they cause can be severe.
Symptoms of Coronavirus
Symptoms of coronavirus illness vary depending on the specific virus. For the milder strains, respiratory symptoms like a runny nose, headache, cough, sore throat, fever and fatigue are common. If an infection progresses to something more severe, it can cause pneumonia, bronchitis, kidney failure and even death. This is more likely to happen in children, the elderly and people with weakened immune systems.
Certain more severe coronavirus infections have caused concern worldwide.
- COVID-19 was first recognized in late 2019. Early diagnoses were linked to an animal market, suggesting animal-to-person infection. Since then, the number of cases has grown among people not exposed to these animals, and person-to-person transmission has been confirmed. This is an ongoing investigation, but at this time the CDC considers the general public in the U.S. at low risk.
- For the most updated information on the outbreak and public health response, visit the CDC's coronavirus webpage.
- Updates from the American Lung Association on COVID-19.
- MERS was first identified in Saudi Arabia in 2012. The MERS virus causes flu-like symptoms, with most patients developing pneumonia. Around one-third of patients diagnoses with MERS have died, according to the CDC. MERS is still active in the Middle East, which is why recent travel to that region should raise suspicion if you are experiencing respiratory illness.
- SARS was a rapidly progressive respiratory illness that started in China in 2003 but spread worldwide before it was contained. Most people who contracted SARS had severe symptoms that required hospitalization. SARS was fatal for 1 in 10 patients, though most made a full recovery. There have been no cases of SARS anywhere in the world since 2004.
Treating and Preventing Coronaviruses
There are currently no specific vaccines or treatments for human coronavirus infections. Antibiotics have been found to be ineffective. However, most patients with milder diseases recover on their own without complications. They can be treated at home and take over-the-counter medication for symptoms such as fever and pain.
Similar to avoiding spreading other infections like the cold or the flu, coronaviruses are spread through contact. So the best way to protect from infection is to avoid touching people who are infected and wash your hands often. Try to avoid touching your eyes, nose and mouth. If you think you are infected, stay home and avoid crowds and contact with others. Keep others safe by covering your mouth when you cough or sneeze and disinfect the objects and surfaces you touch.
Last Updated March 2, 2020
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