COVID-19 is the disease caused by SARS-CoV-2, the coronavirus that emerged in December 2019. Learn about symptoms, diagnosis, treatment and prevention.
What is COVID-19?
COVID-19 is the disease caused by SARS-CoV-2, the coronavirus that emerged in December 2019.
Coronaviruses are a type of virus. There are many different kinds, and some, like COVID-19, cause disease and sometimes death.
What You Need to Know
- COVID-19 can be severe, and has caused millions of deaths around the world as well as lasting health problems in some who have survived the illness.
- However, some with COVID-19 develop only mild symptoms—or experience no symptoms at all.
- The best way to protect yourself is to get vaccinated, wash your hands, and follow respiratory etiquette. If you think you may have COVID-19, follow testing guidelines, wear a mask, and practice physical distancing.
What are symptoms of COVID-19?
COVID-19 symptoms include:
- Cough
- Fever or chills
- Shortness of breath or difficulty breathing
- Muscle or body aches
- Sore throat
- New loss of taste or smell
- Diarrhea
- Headache
- New fatigue
- Nausea or vomiting
- Congestion or runny nose
Some people infected with COVID-19 have mild illness, and others have no symptoms at all. In some cases, however, COVID-19 can lead to respiratory failure, lasting lung and heart muscle damage, nervous system problems, kidney failure or death.
If you have a fever or any of the symptoms listed above, call your doctor or a health care provider and explain your symptoms over the phone before going to the doctor’s office, urgent care facility or emergency room.
CALL 911 if you have a medical emergency such as severe shortness of breath or difficulty breathing.
How long do COVID-19 symptoms last?
Active illness can last one to two weeks if you have mild or moderate coronavirus disease, but severe cases can last months. Some people are asymptomatic, meaning they never have symptoms but do have COVID-19.
Post-COVID-19 symptoms, such as lingering cough, on and off fever, weakness, and changes to your senses of smell or taste, can persist for weeks or even months after you recover from acute illness. Persistent symptoms are sometimes known as long COVID-19.
How does COVID-19 spread?
COVID-19 is spread through droplets and virus particles released into the air when an infected person breathes, talks, laughs, sings, coughs or sneezes.
Larger droplets may fall to the ground in a few seconds, but tiny infectious particles can linger in the air and accumulate in indoor places, especially where many people are gathered and there is poor ventilation. This is why mask-wearing, hand hygiene and isolation practices for people infected with COVID-19 are essential to preventing COVID-19 transmission.
What is the incubation period for COVID-19?
Symptoms show up in people within two to 14 days of exposure to the virus. A person infected with COVID-19 is contagious to others for up to two days before symptoms appear, and they remain contagious to others for 10 to 20 days, depending upon their immune system and the severity of their illness.
How is COVID-19 diagnosed?
COVID-19 is diagnosed through a test. Diagnosis by examination alone is difficult since many COVID-19 signs and symptoms can be caused by other illnesses. Some people do not have symptoms at all.
There are two basic types of tests for COVID-19.
Viral test: This test can tell you if you are currently infected with the coronavirus. A swab is placed in the nose or mouth to gather samples. There are two types of viral tests: laboratory tests (sometimes called polymerase chain reaction [PCR] tests), and rapid tests that detect portions of the virus called antigens.
- Laboratory coronavirus testsare given by health care professionals, and results may take a day or more to receive. Since the samples are analyzed in a laboratory, they are very accurate and are often recommended for people with COVID-19 symptoms.
- Rapid antigen testsmay be performed in pharmacies or health care facilities, or as self-tests at home. Rapid tests provide results in about 15 minutes. These tests are recommended if you do not have symptoms or if you are taking the test as a risk-prevention measure, such as before going on a work trip or seeing a friend, and you want to be sure you don’t have the coronavirus that causes COVID-19.
Antibody test: This is a blood test that can show if you were previously exposed to or infected with the virus that causes COVID-19, and if your body has created antibodies in an attempt to defend itself. It takes at least 12 days after exposure for your body to make enough antibodies to show up on a test. Antibody tests are not recommended to determine if you currently have COVID-19.
This test helps scientists gather data about how the immune system fights off COVID-19 in recovered patients. A positive antibody test means the person has some level of immune protection either from prior infection or from vaccination, but it is not a guarantee of protection from getting re-infected with the virus. Antibody levels decrease over time, and it is not clear how long antibody protection lasts.
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What are risk factors for COVID-19?
Anyone can catch COVID-19, but some people are at higher risk for serious infection. They include people age 65 and older, women who are pregnant and people with certain illnesses. COVID-19 vaccines (and additional doses when appropriate) are especially recommended for people in these groups.
How is COVID-19 treated?
Treatment for COVID-19 depends on the severity of the infection. For milder illness, resting at home and taking medicine to reduce fever is often sufficient. More severe cases may require hospitalization, with treatment that might include intravenous medications, supplemental oxygen, assisted ventilation and other supportive measures
How do you protect yourself from COVID-19?
There are several COVID-19 vaccines recommended by the CDC. Learn more about the COVID-19 vaccine.
In addition, it helps to keep up with other safety precautions, such as following testing guidelines, wearing a mask, washing your hands and staying at home when you are sick.
Are there different variants of COVID-19?
Yes, there are different variants of this coronavirus. Like other viruses, the coronavirus that causes COVID-19 can change (mutate). Mutations may enable the coronavirus to spread faster from person to person. More infections can result in more people getting very sick and also create more opportunity for the virus to develop further mutations.
