Coronavirus disease 2019 (COVID-19)
Coronavirus disease 2019 (COVID-19) is a respiratory illness that causes fever, coughing, and shortness of breath, but many other symptoms can occur. COVID-19 is caused by a highly infectious virus. Most people get mild to moderate illness. Older adults and people with certain health conditions are at high risk for severe illness and death. More than one million people in the United States have died from COVID-19.
Shortness of breath
Breathing difficulty may involve:Difficult breathing Uncomfortable breathingFeeling like you are not getting enough air
Read Article Now Book Mark ArticleCauses
COVID-19 is caused by the SARS-CoV-2 virus (severe acute respiratory syndrome coronavirus 2). Coronaviruses are a family of viruses that can affect people and animals. They can cause mild to moderate respiratory illnesses, such as the common cold. Some coronaviruses can cause severe illness that can lead to pneumonia and even death.
Coronaviruses
Coronaviruses are a family of viruses. Infection with these viruses generally causes mild to moderate respiratory illnesses, such as the common cold...
Read Article Now Book Mark ArticleCommon cold
The common cold most often causes a runny nose, nasal congestion, and sneezing. You may also have a sore throat, cough, headache, or other symptoms....
Read Article Now Book Mark ArticleCOVID-19
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a respiratory illness that ranges from mild symptoms to pneumonia or even death. Symptoms occur within 2 to 14 days from exposure to the virus and may include fever, cough, shortness of breath, chills, muscle pain, headache, sore throat, and new loss of sense of taste or smell. COVID-19 may be more severe in people who are older or who have chronic health conditions, such as heart disease or diabetes.
COVID-19 most readily spreads to people within close contact (about 6 feet or 2 meters). When someone with the illness coughs, sneezes, sings, talks, or breathes, droplets and very small particles spray into the air. You can catch the illness if you breathe in these droplets or particles or they land on your eyes, nose, or mouth.
In some instances, COVID-19 may spread through the air and infect people who are more than 6 feet away. Small droplets and particles can remain in the air for minutes to hours. This is called airborne (or aerosol) transmission, and it occurs especially in enclosed spaces with poor ventilation. However, it is more common for COVID-19 to spread through close contact.
Less often, the illness can spread if you touch a surface with the virus on it, and then touch your eyes, nose, mouth, or face. But this is thought to be a much less common way in which the virus spreads.
COVID-19 can spread from person to person quickly. As the virus spreads, it can change, and new variants of the virus will occur. Different variants may spread more quickly or be more resistant to treatments or vaccines. Taking steps to slow the spread of the virus, such as by getting a COVID-19 vaccine, can help slow the development of new variants.
While the United States Federal COVID-19 Public Health Emergency has ended, COVID-19 is still a health concern, in particular for people at high risk of serious illness.
Symptoms
COVID-19 symptoms range from mild to severe. Older people and people with certain existing health conditions have a higher risk of developing severe illness and death. Health conditions that increase this risk include:
COVID-19 symptoms
COVID-19 is a highly infectious respiratory illness caused by a virus called SARS-CoV-2. COVID-19 symptoms can range from mild to severe. Symptoms m...
Read Article Now Book Mark Article- Asthma (if it's moderate or severe)
- Cancer
- COPD (chronic obstructive pulmonary disease)
COPD (chronic obstructive pulmonary dis...
Chronic obstructive pulmonary disease (COPD) is a common lung disease. Having COPD makes it hard to breathe. There are two main forms of COPD:Chroni...
Read Article Now Book Mark Article - Cystic fibrosis
Cystic fibrosis
Cystic fibrosis is a disease that causes thick, sticky mucus to build up in the lungs, digestive tract, and other areas of the body. It is one of th...
Read Article Now Book Mark Article - Dementia
Dementia
Dementia is a loss of brain function that occurs with certain diseases. It affects one or more brain functions such as memory, thinking, language, j...
Read Article Now Book Mark Article - Diabetes (type 1 and type 2)
Diabetes
Diabetes is a long-term (chronic) disease in which the body cannot regulate the amount of sugar in the blood.
Read Article Now Book Mark Article - Down syndrome or other disabilities
- Heart disease and stroke
Heart disease
Cardiovascular disease is the broad term for problems with the heart and blood vessels. These problems are often due to atherosclerosis. This condi...
Read Article Now Book Mark ArticleStroke
A stroke occurs when blood flow to a part of the brain stops. A stroke is sometimes called a "brain attack. " If blood flow is cut off for longer th...
Read Article Now Book Mark Article - HIV
- Kidney, lung, or liver disease
Kidney
Chronic kidney disease is the slow loss of kidney function over time. The main job of the kidneys is to remove wastes and excess water from the body...
Read Article Now Book Mark ArticleLung
Lung disease is any problem in the lungs that prevents the lungs from working properly. There are three main types of lung disease:Airway diseases -...
Read Article Now Book Mark ArticleLiver disease
The term "liver disease" applies to many conditions that stop the liver from working or prevent it from functioning well. Abdominal pain or swelling...
Read Article Now Book Mark Article - Mental health conditions
- Overweight and obesity (BMI of 25 kg per square meter or above)
Obesity
Obesity means weighing more than what is healthy for a given height. Obesity is a serious, chronic disease. It can lead to other health problems, i...
Read Article Now Book Mark Article - Physical inactivity
- Pregnancy
- Organ or stem cell transplantation
- Sickle cell disease or thalassemia
Sickle cell disease
Sickle cell disease is a disorder passed down through families. The red blood cells that are normally shaped like a disk take on a sickle or crescen...
Read Article Now Book Mark ArticleThalassemia
Thalassemia is a blood disorder passed down through families (inherited) in which the body makes an abnormal form or inadequate amount of hemoglobin....
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- Substance use disorders
Substance use disorders
Substance use disorder occurs when a person's use of alcohol or another substance (prescribed medicine or illegal drug) leads to health issues or pro...
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- Weak immune system (immunocompromised)
Symptoms of COVID-19 may include:
- Fever
Fever
Fever is the temporary increase in the body's temperature in response to a disease or illness. A child has a fever when the temperature is at or abov...
Read Article Now Book Mark Article - Chills
- Cough
Cough
Coughing is an important way to keep your throat and airways clear. But too much coughing may mean you have a disease or disorder. Some coughs are d...
Read Article Now Book Mark Article - Shortness of breath or difficulty breathing
Shortness of breath
Breathing difficulty may involve:Difficult breathing Uncomfortable breathingFeeling like you are not getting enough air
Read Article Now Book Mark Article - Fatigue
- Muscle aches
- Headache
- Loss of sense of taste or smell
- Sore throat
- Stuffy or runny nose
- Nausea or vomiting
- Diarrhea
This is not a complete list of possible symptoms. Symptoms may change with new variants of the virus.
Some people may have no symptoms at all. Many people have some, but not all of these symptoms. Symptoms can also vary, depending on whether you are vaccinated and boosted.
Symptoms may appear within 2 to 14 days after being exposed. Most often, symptoms appear around 5 days after exposure. However, you can spread the virus even when you do not have symptoms.
More severe symptoms that require seeking medical help right away include:
- Trouble breathing
Trouble breathing
Breathing difficulty may involve:Difficult breathing Uncomfortable breathingFeeling like you are not getting enough air
Read Article Now Book Mark Article - Chest pain or pressure that persists
Chest pain
Chest pain is discomfort or pain that you feel anywhere along the front of your body between your neck and upper abdomen.
Read Article Now Book Mark Article - Confusion or inability to wake up
- Blue lips or face
- Any other symptoms that are severe or that concern you
Exams and Tests
If you have symptoms of COVID-19, you can perform a self-test. Your health care provider also may decide to test you for the disease.
Self-test
Self-testing for COVID-19 can be done using an over-the-counter (OTC) rapid antigen test to find out if you have COVID-19 infection. An OTC test for...
Read Article Now Book Mark ArticleIf you get tested for COVID-19, swabs from the back of the nose, the front of the nose, or the throat will be collected to test for SARS-CoV-2.
Tested for COVID-19
Testing for the virus that causes COVID-19 involves taking a mucus sample from your upper respiratory tract. This test is used to diagnose COVID-19....
Read Article Now Book Mark ArticleTreatment
If you are recovering at home, supportive care is given to help relieve symptoms. People with severe illness will be treated in the hospital.
The types of medicines given may vary depending upon how sick you are, your risk factors for serious illness from the disease, your age, and possibly what variant of the virus is causing the infection.
If you test positive for COVID-19, your provider may recommend antiviral medicines.
If given soon after you become infected (5 to 7 days, depending on the medicine), these medicines help your immune system fight off the virus. They may be given to adults and children with mild to moderate illness who are not hospitalized. These medicines include:
- Nirmatrelvir with ritonavir (Paxlovid), an antiviral medicine, to help slow the virus. It is a pill you take at home.
- Remdesivir (Veklury), an antiviral medicine, to help slow the virus. This medicine is given through the vein (IV). You will need to go to a health care facility for 3 days in a row to receive this medicine.
- Molnupiravir (Lagevrio), an antiviral medicine used only for adults. It is a pill you take at home.
If you are being cared for in the hospital and are receiving oxygen therapy, treatment for COVID-19 may include the following medicines:
- Remdesivir, an antiviral medicine, to help slow the virus.
- Dexamethasone, a steroid medicine, to help reduce an overactive immune response in the body. If dexamethasone is not available, you may be given another corticosteroid such as prednisone, methylprednisolone, or hydrocortisone.
- You may be given one or the other medicine or both medicines together.
- Baricitinib or tocilizumab to help reduce immune system activity, depending on your condition.
- Medicines for any complications from the disease. For example, you may be given blood thinners to help reduce the chance of blood clots, or you may have dialysis if your kidneys do not function properly.
Based on available evidence, current treatment guidelines from the National Institutes of Health recommend against using some drugs for COVID-19, including chloroquine, hydroxychloroquine, and ivermectin. Do not take any drugs to treat COVID-19 except those prescribed by your provider. Check with your provider before treating yourself or a loved one with vitamins, nutrients, or any medicines prescribed in the past for other health problems. Since some COVID-19 medicines have interactions with other medicines or supplements you may be taking, always check with your provider before starting them.
Possible Complications
Complications can include:
- Long COVID, which is defined by lasting COVID-19 symptoms that continue 4 weeks or longer after infection with the virus (post-acute sequelae of SARS CoV-2 infection [PASC])
Long COVID
Most people who have COVID-19 recover completely. Some people continue to have health problems after having COVID-19. This is called long COVID. Lo...
Read Article Now Book Mark Article - Damage to the heart and blood vessels, kidneys, brain, skin, eyes, and gastrointestinal organs
- Respiratory failure
- Death
When to Contact a Medical Professional
You should contact your provider:
- If you have symptoms and think you may have COVID-19
- If you have COVID-19 and you are in a group for whom antiviral medicine may be given
- If you have COVID-19 and your symptoms are getting worse
Call 911 or the local emergency number if you have:
- Trouble breathing
- Chest pain or pressure
- Confusion or inability to wake up
- Blue lips or face
- Any other symptoms that are severe or concern you
Prevention
You can take steps to protect yourself and others from COVID-19:
Protect yourself and others from COVID-...
Coronavirus disease 2019 (COVID-19) is a serious disease, mainly of the respiratory system, affecting many people around the globe. It can cause mil...
Read Article Now Book Mark Article- Get a COVID-19 vaccine.
COVID-19 vaccine
COVID-19 vaccines are used to prepare the body's immune system to protect against COVID-19. Everyone ages 6 months and older should get a 2024-2025 C...
Read Article Now Book Mark Article - If you have children, make sure they get a COVID-19 vaccine.
COVID-19 vaccine
COVID-19 vaccines are used to prepare the body's immune system to protect against COVID-19.
Read Article Now Book Mark Article - If you have COVID-19 or have symptoms of it stay at home and avoid contact with other people.
Stay at home and avoid contact with oth...
Using antibiotics incorrectly can cause some bacteria to change or permit resistant bacteria to grow. These changes make bacteria stronger, so most ...
Read Article Now Book Mark Article - Wear a well-fitted face mask or respirator.
Face mask or respirator
In places where respiratory viruses are spreading, wearing a face mask in public helps protect other people from possible infection with viruses such...
Read Article Now Book Mark Article - Practice good hygiene. Cover your mouth and nose with a tissue or your sleeve (not your hands) when coughing or sneezing.
- Wash your hands many times a day with soap and running water for at least 20 seconds. Use an alcohol-based hand sanitizer (at least 60% alcohol) if soap and water are not available.
Wash your hands many times a day
Washing your hands often during the day is an important way to help reduce the spread of germs and prevent illness. Learn when you should wash your ...
Read Article Now Book Mark Article - Take steps for cleaner air in your home. Open windows, use fans and portable high-efficiency particulate air (HEPA) cleaners, and setting the fan on your furnace or air conditioning to "on."
Reviewed By
Frank D. Brodkey, MD, FCCM, Associate Professor, Section of Pulmonary and Critical Care Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. Editorial update 07/24/2024.
Centers for Disease Control and Prevention website. Types of COVID-19 treatment. www.cdc.gov/covid/treatment/. Updated July 12, 2024. Accessed July 24, 2024.
Centers for Disease Control and Prevention website. COVID-19 vaccine frequently asked questions. www.cdc.gov/covid/vaccines/faq.html. Updated July 5, 2024. Accessed July 24, 2024.
Centers for Disease Control and Prevention website. Long COVID basics. www.cdc.gov/covid/long-term-effects/. Updated July 11, 2024. Accessed July 24, 2024.
Centers for Disease Control and Prevention website. Respiratory virus guidance. www.cdc.gov/respiratory-viruses/guidance/index.html. Updated March 1, 2024. Accessed March 5, 2024.
Centers for Disease Control and Prevention website. Staying up to date with COVID-19 vaccines. www.cdc.gov/covid/vaccines/stay-up-to-date.html. Updated July 3, 2024. Accessed July 24, 2024.