Overview
Coronaviruses are a family of viruses that can cause illnesses such as the common cold, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). In 2019, a new coronavirus was identified as the cause of a disease outbreak that originated in China.
The virus is now known as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease it causes is called coronavirus disease 2019 (COVID-19). In March 2020, the World Health Organization (WHO) declared the COVID-19 outbreak a pandemic.
Public health groups, including the U.S. Centers for Disease Control and Prevention (CDC) and WHO, are monitoring the pandemic and posting updates on their websites. These groups have also issued recommendations for preventing and treating the illness.
Symptoms
Signs and symptoms of coronavirus disease 2019 (COVID-19) may appear two to 14 days after exposure. This time after exposure and before having symptoms is called the incubation period. Common signs and symptoms can include:
Early symptoms of COVID-19 may include a loss of taste or smell.
Other symptoms can include:
This list is not all inclusive. Other less common symptoms have been reported, such as rash, nausea, vomiting and diarrhea. Children have similar symptoms to adults and generally have mild illness.
The severity of COVID-19 symptoms can range from very mild to severe. Some people may have only a few symptoms, and some people may have no symptoms at all. Some people may experience worsened symptoms, such as worsened shortness of breath and pneumonia, about a week after symptoms start.
People who are older have a higher risk of serious illness from COVID-19, and the risk increases with age. People who have existing chronic medical conditions also may have a higher risk of serious illness. Serious medical conditions that increase the risk of serious illness from COVID-19 include:
Other conditions may increase the risk of serious illness, such as:
When to see a doctor
If you have COVID-19 symptoms or you've been in contact with someone diagnosed with COVID-19, contact your doctor or clinic right away for medical advice. Tell your health care team about your symptoms and possible exposure before you go to your appointment.
If you have emergency COVID-19 signs and symptoms, seek care immediately. Emergency signs and symptoms can include:
If you have signs or symptoms of COVID-19, contact your doctor or clinic for guidance. Let your doctor know if you have other chronic medical conditions, such as heart disease or lung disease. During the pandemic, it's important to make sure health care is available for those in greatest need.
Causes
The virus appears to spread easily among people, and more continues to be discovered over time about how it spreads. Data has shown that it spreads from person to person among those in close contact (within about 6 feet, or 2 meters). The virus spreads by respiratory droplets released when someone with the virus coughs, sneezes or talks. These droplets can be inhaled or land in the mouth or nose of a person nearby.
It can also spread if a person touches a surface with the virus on it and then touches his or her mouth, nose or eyes, although this isn't considered to be a main way it spreads.
Risk factors
Risk factors for COVID-19 appear to include:
Complications
Although most people with COVID-19 have mild to moderate symptoms, the disease can cause severe medical complications and lead to death in some people. Older adults or people with existing chronic medical conditions are at greater risk of becoming seriously ill with COVID-19.
Complications can include:
More InformationMultisystem inflammatory syndrome in children (MIS-C)
Prevention
Although there is no vaccine available to prevent COVID-19, you can take steps to reduce your risk of infection. WHO and CDC recommend following these precautions for avoiding COVID-19:
If you have a chronic medical condition and may have a higher risk of serious illness, check with your doctor about other ways to protect yourself.
Travel
If you're planning to travel, first check the CDC and WHO websites for updates and advice. Also look for any health advisories that may be in place where you plan to travel. You may also want to talk with your doctor if you have health conditions that make you more susceptible to respiratory infections and complications.