COVID-19 (Coronavirus Disease 2019)

COVID-19 is a contagious illness caused by a virus called SARS-CoV-2 that emerged in late 2019 and spread globally, affecting millions of people and causing nearly 1.2 million deaths in the United States alone by June 2024.

What is COVID-19?
Symptoms of COVID-19
How COVID-19 spreads
Who is at higher risk for severe illness
Possible complications
Diagnosis and testing
Treatment options
Taking care of yourself at home
How to protect yourself and others

What is COVID-19?

COVID-19 stands for coronavirus disease 2019. It is an illness caused by a virus named SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2)^[1]^[3]. The virus is a type of coronavirus, which is a family of viruses that also cause common colds^[6]. However, this particular coronavirus is new and different from others that have circulated before.

The disease started spreading at the end of 2019, beginning in Wuhan, China^[8]. In March 2020, the World Health Organization declared it a global pandemic, meaning it spread widely around the world^[8]. As of June 1, 2024, nearly 1.2 million people have died of COVID-19 in the United States^[1].

COVID-19 can be very contagious and spreads quickly from person to person^[1]. Most people infected with the virus will experience mild to moderate illness and recover without requiring special treatment^[2]. However, some people become seriously ill and require medical attention^[1].

The virus that causes COVID-19 keeps changing over time. Since the pandemic began, different variants of the virus have emerged, including alpha, beta, gamma, delta, and omicron^[6]. These changes occur naturally as viruses reproduce and can lead to variants that may have new characteristics, including different ways of spreading^[1].

Symptoms of COVID-19

COVID-19 affects different people in different ways. Most common symptoms show up 2 to 14 days after contact with the virus^[3]. The illness most often causes problems with breathing, similar to a cold, the flu, or pneumonia (an infection in the lungs)^[1].

Most common symptoms include:

Fever or feeling hot to touch on your chest or back
Cough (often dry and continuous)
Extreme tiredness, called fatigue
Loss of taste or smell
Shortness of breath or trouble breathing

^[2]^[3]^[6]

Less common symptoms include:

Sore throat
Headache
Body aches and muscle or joint pain
Chills or shivering
Stuffy or runny nose
Upset stomach, nausea, vomiting, or loose stools (diarrhea)
A rash on skin
Red or irritated eyes

^[2]^[6]^[17]

Some people have no symptoms at all but can still spread the virus to others^[6]. Some people, including those with minor or no symptoms, will develop what is called Post-COVID Conditions or “Long COVID,” where symptoms continue for months after the initial infection^[1].

Most people feel better within a few weeks, but recovery can take longer for some^[17]. The symptoms of COVID-19 are very similar to symptoms of other illnesses, such as colds and flu^[17].

How COVID-19 spreads

COVID-19 spreads when an infected person breathes out droplets and very small particles that contain the virus^[1]. The virus can spread through the air in tiny droplets of fluid^[3]. Other people can breathe in these droplets and particles, or these droplets and particles can land on their eyes, nose, or mouth^[1].

The virus spreads most commonly between people who are in close contact with each other^[3]. You can get it from someone coughing, sneezing, speaking, singing, or even just breathing near you^[2]^[6]. You might also get it from touching contaminated objects and surfaces, then touching your face^[6].

Anyone infected with COVID-19 can spread it, even if they do not have symptoms^[1]. In some circumstances, droplets with the virus may contaminate surfaces that people touch^[1]. COVID-19 can even spread from people to animals in some situations^[1].

Who is at higher risk for severe illness

Some people are more likely than others to get very sick if they get COVID-19^[1]. Understanding your risk can help you make decisions to protect yourself and others.

People at higher risk include those who:

Are older, especially those ages 65 years or older
Are pregnant
Smoke or used to smoke
Are not vaccinated or are not up to date on their COVID-19 vaccinations
Have a weakened immune system (are immunocompromised)
Have received a solid organ or stem cell transplant

^[1]^[6]^[9]

People with certain medical conditions are also at increased risk:

Blood disorders such as sickle cell disease
Cancer
Stroke or other brain blood vessel diseases
Chronic conditions affecting the lungs, kidneys, liver, or heart
Birth conditions like cerebral palsy or Down syndrome
Diabetes (Type 1 or Type 2)
HIV/AIDS
Mental health conditions
Brain and nervous system conditions, like dementia or Alzheimer’s disease
Obesity
Substance use disorders

^[6]

Older people and those with underlying medical conditions like heart disease, diabetes, chronic breathing disease, or cancer are more likely to develop serious illness^[2]. However, anyone can get sick with COVID-19 and become seriously ill or die at any age^[2].

Possible complications

COVID-19 can cause serious complications, even if you don’t feel very sick at first^[6]. While COVID-19 may attack your lungs and breathing system, other parts of your body may also be affected by the disease^[1].

Serious complications can include:

Pneumonia (infection in the lungs)
Acute respiratory distress syndrome (ARDS), a severe breathing problem
Blood clots, including pulmonary embolism (a clot in the lung) or deep vein thrombosis (a clot in a leg vein)
Heart inflammation (swelling of the heart muscle or the sac around the heart)
Cardiac arrest (when the heart stops beating)
Multisystem inflammatory syndrome in children (MIS-C), a rare but serious condition affecting children
Long COVID, a condition where pain, extreme fatigue, and other symptoms last for months or years after a COVID infection

^[6]

Diagnosis and testing

If you have symptoms of COVID-19 or you’ve been exposed to someone with the virus, you should get tested^[11]. Testing for COVID-19 can help you decide what to do next, like getting treatment to reduce your risk of severe illness and taking steps to lower your chances of spreading the virus to others^[9]^[18].

Healthcare providers diagnose COVID-19 by swabbing your nose with a soft-tipped stick and testing it with a nucleic acid amplification test (NAAT), like a PCR test^[6]. PCR tests are more accurate than other types of COVID-19 tests^[11].

You can also test at home with a rapid antigen test^[6]. At-home COVID-19 tests are available in the United States, and the U.S. Food and Drug Administration approves or authorizes these tests^[11]. When taking a test at home, carefully read the directions that come with the test and follow the instructions exactly to get as accurate a result as possible^[11].

Guidelines for when to take a COVID-19 test:

If you have COVID-19 symptoms, test for the illness right away
If you were exposed to the COVID-19 virus but don’t have symptoms, wait at least five days after exposure and then test
If you have symptoms and tested positive for COVID-19 within the last 30 days, you can test again

^[11]

COVID-19 tests use a sample taken from your nose or throat, or a sample of saliva^[11]. If you think you could have COVID-19, contact your healthcare provider before going to the office^[11]. If you don’t have a healthcare provider, contact your local pharmacy, community health center, or health department^[9].

Treatment options

If you have COVID-19 and are more likely to get very sick, medications are available that can reduce your risk of being hospitalized and death^[9]. COVID-19 can be treated with antiviral medications, which are medicines that target specific parts of the virus to stop it from multiplying in the body^[9]^[6].

Important facts about treatment:

Don’t delay: Treatments must be started within 5 to 7 days after you first develop symptoms to be effective
You do not need a positive test to start treatment, so if you get sick and are at high risk for severe illness, talk to your healthcare provider as soon as possible
Treatment can help prevent severe illness, hospitalization, and death from COVID-19

^[9]

Available antiviral treatments include:

Nirmatrelvir with Ritonavir (Paxlovid): Taken at home by mouth for adults and children ages 12 years and older. Must begin within 5 days of when symptoms start
Remdesivir (Veklury): Given through an IV (intravenous infusion) at a healthcare facility for 3 days in a row for adults and children. Must begin within 7 days of when symptoms start
Molnupiravir (Lagevrio): Taken at home by mouth for adults. Must begin within 5 days of when symptoms start

^[9]^[10]

Not everyone with COVID-19 needs to get treated with these medications^[14]. A doctor will advise which treatment is most suitable for you based on your individual situation^[10]. Some treatments might have side effects, so your healthcare provider will discuss the benefits and risks with you^[9].

Taking care of yourself at home

Many people with COVID-19 get better with rest, fluids, and treatment for their symptoms^[6]. Most people with COVID-19 have mild illness and can take care of themselves at home^[23].

To care for yourself at home:

Get plenty of rest to help your body fight the virus
Drink plenty of water or other fluids to stay hydrated. Good choices include water, soup, fruit juice, and hot tea with lemon
Take medicine you can get without a prescription to help with symptoms. You can take acetaminophen (such as Tylenol) or ibuprofen (Advil, Motrin) to reduce fever and help with pain
Use petroleum jelly on sore skin around your nose if it becomes irritated from rubbing with tissues
Try a teaspoon of honey to soothe a sore throat or relieve a cough (but only for people over 12 months old)

^[16]^[19]^[23]

For breathing problems:

Breathe slowly in through your nose and out through your mouth, with your lips together like you’re gently blowing out a candle
Sit upright in a chair to help with shortness of breath
Relax your shoulders so you’re not hunched
Lean forward slightly and support yourself by putting your hands on your knees or on something stable like a chair
Don’t lie on your back if you have a cough – lie on your side or sit upright instead

^[17]

Skip these while you’re sick:

Don’t drink milk, soda, alcohol, or coffee
Don’t exercise, especially long or intense workouts

^[19]

When to seek emergency medical care:

Severe trouble breathing (you can’t speak a full sentence)
Constant chest pain or pressure
Severe dizziness or feeling lightheaded
Confusion or difficulty thinking clearly
Blue color on your face and lips
Passing out or being very hard to wake up

^[16]^[17]

If you notice any of these emergency warning signs, call your healthcare provider or emergency services right away^[16].

How to protect yourself and others

The best way to prevent and slow down the spread of COVID-19 is to be well informed about the disease and how the virus spreads^[2]. There are many actions you can take to help protect you, your household, and your community from COVID-19^[1].

Core prevention strategies include:

Stay up to date with COVID-19 vaccines. Although vaccinated people sometimes get infected with the virus, staying up to date on COVID-19 vaccines significantly lowers the risk of getting very sick, being hospitalized, or dying from COVID-19^[18]. Get vaccinated when a vaccine is available to you^[2].

Practice good hygiene. Wash your hands regularly with soap and water and scrub for at least 20 seconds, especially after you cough or sneeze^[2]^[20]. If soap and water aren’t available, use an alcohol-based hand sanitizer^[20].

Take steps for cleaner air. Choose open, well-ventilated spaces over closed ones. Open a window if indoors^[2]^[20].

Use precautions when you are sick. If you have symptoms, stay home and away from others, including people you live with who are not sick^[18]. Try to stay at home and avoid contact with other people for 3 days after the day you tested positive if you or your child are under 18 years old, or for 5 days if you are 18 years old or over^[17].

Additional prevention strategies:

Wear a mask. Wear a properly fitted mask when physical distancing is not possible or when in poorly ventilated settings^[2]^[20]. A mask that fits snugly over your nose and mouth without gaps can help stop the spread of the virus when you cough, sneeze, or speak^[1].

Keep your distance. Stay at least 1 meter (about 3 feet) apart from others, even if they don’t appear to be sick^[2]^[20]. Putting distance between yourself and others can help lower the risk of COVID-19 transmission^[18].

Cover your mouth and nose. Practice good breathing habits by coughing into a flexed elbow and staying home until you recover if you feel unwell^[2]^[20]. Cover your mouth and nose with a tissue when you cough or sneeze, then throw it in the trash right away^[20].

Clean surfaces. Clean and disinfect surfaces you touch frequently in your home, such as doorknobs, remote controls, phones, handles on appliances, countertops, tabletops, bathrooms, and computer keyboards^[20].

Don’t share personal items. Avoid sharing bedding, towels, cups and glasses, and eating utensils with others^[20].

Using these prevention strategies can be especially helpful when respiratory viruses are causing a lot of illness in your community, when you or those around you have risk factors for severe illness, or when you or those around you were recently exposed to the virus^[18].