Editor's note: For the latest updates on the 2021 coronavirus outbreak, see our news coverage.
What Is COVID-19?
COVID-19 is a disease caused by SARS-CoV-2 that can trigger what doctors call a respiratory tract infection. It can affect your upper respiratory tract (sinuses, nose, and throat) or lower respiratory tract (windpipe and lungs).
It spreads the same way other coronaviruses do, mainly through person-to-person contact. Infections range from mild to deadly.
SARS-CoV-2 is one of seven types of coronavirus, including the ones that cause severe diseases like Middle East respiratory syndrome (MERS) and sudden acute respiratory syndrome (SARS). The other coronaviruses cause most of the colds that affect us during the year but aren’t a serious threat for otherwise healthy people.
Is there more than one strain of SARS-CoV-2?
An early Chinese study of 103 COVID-19 cases found two strains, which they named L and S. The S type is older, but the L type was more common in early stages of the outbreak. They think one may cause more cases of the disease than the other, but they’re still working on what it all means.
It is also normal for a virus to change, or mutate, as it infects people and this virus has done so. There are several variants which are now spreading, some proving to be more contageous as well as more deadly than the original virus.
How long will the coronavirus last?
There's no way to tell how long the pandemic will continue. There are many factors, including the public’s efforts to slow the spread, researchers’ work to learn more about the virus, their search for a treatment, and the success of the vaccines.
Symptoms of COVID-19
The main symptoms include:
- Shortness of breath
- Trouble breathing
- Chills, sometimes with shaking
- Body aches
- Sore throat
- Congestion/runny nose
- Loss of smell or taste
The virus can lead to pneumonia, respiratory failure, heart problems, liver problems, septic shock, and death. Many COVID-19 complications may be caused by a condition known as cytokine release syndrome or a cytokine storm. This is when an infection triggers your immune system to flood your bloodstream with inflammatory proteins called cytokines. They can kill tissue and damage your organs. In some cases, lung transplants have been needed.
If you notice the following severe symptoms in yourself or a loved one, get medical help right away:
- Trouble breathing or shortness of breath
- Ongoing chest pain or pressure
- New confusion
- Can’t wake up fully
- Bluish lips or face
Strokes have also been reported in some people who have COVID-19. Remember FAST:
- Face. Is one side of the person’s face numb or drooping? Is their smile lopsided?
- Arms. Is one arm weak or numb? If they try to raise both arms, does one arm sag?
- Speech. Can they speak clearly? Ask them to repeat a sentence.
- Time. Every minute counts when someone shows signs of a stroke. Call 911 right away.
If you’re infected, symptoms can show up in as few as 2 days or as many as 14. It varies from person to person.
According to researchers in China, these were the most common symptoms among people who had COVID-19:
- Fever 99%
- Fatigue 70%
- Cough 59%
- Lack of appetite 40%
- Body aches 35%
- Shortness of breath 31%
- Mucus/phlegm 27%
Some people who are hospitalized for COVID-19 have also have dangerous blood clots, including in their legs, lungs, and arteries.
What to do if you think you have it
If you live in or have traveled to an area where COVID-19 is spreading:
- If you don’t feel well, stay home. Even if you have mild symptoms like a headache and runny nose, stay in until you’re better. This lets doctors focus on people who are more seriously ill and protects health care workers and people you might meet along the way. You might hear this called self-quarantine. Try to stay in a separate room away from other people in your home. Use a separate bathroom if you can.
- Call the doctor if you have trouble breathing. You need to get medical help as soon as possible. Calling ahead (rather than showing up) will let the doctor direct you to the proper place, which may not be your doctor’s office. If you don’t have a regular doctor, call your local board of health. They can tell you where to go for testing and treatment.
- Follow your doctor’s advice and keep up with the news on COVID-19. Between your doctor and health care authorities, you’ll get the care you need and information on how to prevent the virus from spreading.
For more information about COVID-19, see our FAQ.
How do I know if it’s COVID-19, a cold, or the flu?
Symptoms of COVID-19 can be similar to a bad cold or the flu. Your doctor will suspect COVID-19 if:
- You have a fever and a cough.
- You have been exposed to people who have it within the last 14 days.
Cold vs. Flu vs.
Allergies vs. COVID-19
(can range from moderate to severe)
High (100-102 F), Can last 3-4 days
Can be present
General aches, pains
Usual, often severe
Can be present
Intense, starts early, c
Usual gone in 2-3 weeks
Can be present
Has been reported
Has been reported
Has been reported
Mild to moderate
Common, can become severe
Loss of smell and taste
Has been reported
|Pink Eye||Can Happen||Can Happen||Can Happen||Can Happen|
Sometimes in children
Has been reported
|Shortness of Breath||Rare||Rare||Rare, except for those with allergic asthma||In more serious infections|
|Chest Pain||Rare||In more serious infections||Rare||In more serious infections|
Is COVID-19 worse than the flu?
Unlike the flu, a lot of people aren’t immune to the coronavirus because it’s so new. If you do catch it, the virus triggers your body to make things called antibodies. Researchers are looking at whether the antibodies give you protection against catching it again.
The coronavirus also appears to cause higher rates of severe illness and death than the flu. But the symptoms themselves can vary widely from person to person.
Is COVID-19 seasonal like the flu?
While it had hoped intitially that higher temperatures and humidity levels might help slow the spread of the coronavirus, that was not the case. Experts advise caution and say thorough public health efforts have more influence than weather on the spread. Also, past flu pandemics have happened year-round.
Causes of the New Coronavirus
Researchers aren’t sure what caused it and investigations as to its origin are ongoing. . There’s more than one type of coronavirus. They’re common in people and in animals including bats, camels, cats, and cattle. SARS-CoV-2, the virus that causes COVID-19, is similar to MERS and SARS. They all came from bats.
Coronavirus Risk Factors
Anyone can get COVID-19, and most infections are mild. The older you are, the higher your risk of severe illness.
You also a have higher chance of serious illness if you have one of these health conditions:
- Chronic kidney disease
- Chronic obstructive pulmonary disease (COPD)
- A weakened immune system because of an organ transplant
- Serious heart conditions such as heart failure or coronary artery disease
- Sickle cell disease
- Type 2 diabetes
Conditions that could lead to severe COVID-19 illness include:
- Moderate to severe asthma
- Diseases that affect your blood vessels and blood flow to your brain
- Cystic fibrosis
- High blood pressure
- A weakened immune system because of a blood or bone marrow transplant, HIV, or medications like corticosteroids
- Liver disease
- Damaged or scarred lung tissue (pulmonary fibrosis)
- Type 1 diabetes
Some children and teens who are in the hospital with COVID-19 have an inflammatory condition that doctors are calling multisystem inflammatory syndrome in children. Doctors think it may be linked to the virus. It causes symptoms similar to those of toxic shock and of Kawasaki disease, a condition that causes inflammation in kids’ blood vessels.
How does the coronavirus spread?
SARS-CoV-2, the virus, mainly spreads from person to person.
Most of the time, it spreads when a sick person coughs or sneezes. They can spray aerosol droplets 6 feet away or even further. If you breathe them in or swallow them, the virus can get into your body. Some people who have the virus don't have symptoms, but they can still spread the virus.
While less likely, you can also get the virus from touching a surface or object the virus is on, then touching your mouth, nose, or possibly your eyes. Most viruses can live for several hours on a surface that they land on. A study shows that SARS-CoV-2 can last for several hours on various types of surfaces:
- Copper (pennies, teakettles, cookware): 4 hours
- Cardboard (shipping boxes): up to 24 hours
- Plastic (milk containers, detergent bottles, subway and bus seats, elevator buttons):2 to 3 days
- Stainless steel (refrigerators, pots and pans, sinks, some water bottles): 2 to 3 days
That’s why it’s important to wash or sanitize your hands regularly and disinfect surfaces to get rid of the virus.
Some dogs and cats have tested positive for the virus. A few have shown signs of illness. There’s no evidence that humans can catch this coronavirus from an animal, but it appears it can be passed from humans to animals.
What is community spread?
Doctors and health officials use this term when they don’t know the source of the infection. With COVID-19, it usually refers to someone who gets the virus even though they haven’t been out of the country or haven’t been exposed to someone who’s traveled abroad or who has COVID-19.
In February 2020, the CDC confirmed a COVID-19 infection in California in a person who had not traveled to an affected area or been exposed to someone with the disease. This marked the first instance of community spread in the U.S. It’s likely that person was exposed to someone who was infected but didn’t know it. This type of occurrence has been happening with the variants as well.
How fast is it spreading?
The number of people infected by SARS-CoV-2 changes every day. See our news story for the latest updates on this developing story.
How contagious is the coronavirus?
The transmission rate is relatively high. Early research has estimated that one person who has it can spread it to between 2 and 3.5 others. One study found that the rate was higher, with one case spreading to between 4.7 and 6.6 other people. By comparison, one person who has the seasonal flu will pass it to between 1.1 and 2.3 others.
The CDC reports there is evidence it can be transmitted if you get within 6 feet of someone who is infectious for a total of 15 minutes throughout a day. It had previously been believed the exposure had to be 15 minutes at a time.
We can work to lower the transmission rate by wearing cloth face masks when we can’t stay 6 feet away from others, washing hands often, keeping common surfaces clean, limiting contact with other people, and getting vaccinated.
Can coronavirus be transmitted through groceries, packages, or food?
You’re much more likely to get COVID-19 from another person than from packages, groceries, or food. If you’re in a high-risk group, stay home and use a delivery service or have a friend shop for you. Have them leave the items outside your front door, if you can. If you do your own shopping, wear a cloth face mask and try to stay at least 6 feet away from other shoppers.
Wash your hands for at least 20 seconds before and after bringing things into your home. The coronavirus can linger on hard surfaces, so clean and disinfect countertops and anything else your bags have touched. You can wipe down plastic, metal, or glass packaging with soap and water if you want.
There’s no evidence that anyone has gotten COVID-19 from food or food containers.
Call your doctor or local health department if you think you’ve been exposed and have symptoms like:
- Fever of 100 F or higher
- Trouble breathing
Testing facilities readily available in most areas. While some require an appointment, others are simply drive-up. There are also some home testing kits now available.
A swab test is the most common method. It looks for signs of the virus in your upper respiratory tract. The person giving the test puts a swab up your nose to get a sample from the back of your nose and throat. That sample usually goes to a lab that looks for viral material, but some areas may have rapid tests that give results in as little as 15 minutes.
If there are signs of the virus, the test is positive. A negative test could mean there is no virus or there wasn’t enough to measure. That can happen early in an infection. It usually takes 24 hours to get results, but the tests must be collected, stored, shipped to a lab, and processed.
The FDA is granting emergency use authorizations for tests that include home nasal swab tests which you collect yourself and express ship back to the lab for analysis. The agency has also approved several at-home rapid tests. you have to get these through a prescription so the results will be registered. You can receive those results within a few minutes.
A swab test can only tell whether you have the virus in your body at that moment. But you may also consider taking an antibody test which can show whether you’ve ever been exposed to the virus, even if you didn’t have symptoms. This is important in officials’ efforts to learn how widespread COVID-19 is. In time, it might also help them figure out who’s immune to the virus.
The FDA is working with laboratories across the country to develop more tests.
Getting vaccinated against COVID-19 is a key part of prevention. But you should also take these steps:
- Cover your nose and mouth in public. If you have COVID-19, you can spread it even if you don’t feel sick. Wear a cloth face covering to protect others. This isn’t a replacement for social distancing. You still need to keep a 6-foot distance between yourself and those around you. Don’t use a face mask meant for health care workers. And don’t put a face covering on anyone who is:
- Under 2 years old
- Having trouble breathing
- Unconscious or can’t remove the mask on their own for other reasons
- Wash your hands often with soap and water or clean them with an alcohol-based sanitizer. This kills viruses on your hands.
- Don’t touch your face. Coronaviruses can live on surfaces you touch for several hours. If they get on your hands and you touch your eyes, nose, or mouth, they can get into your body.
- Practice social distancing. Because you can have and spread the virus without knowing it, you should stay home as much as possible. If you do have to go out, stay at least 6 feet away from others.
- Clean and disinfect. You can clean first with soap and water, but disinfect surfaces you touch often, like tables, doorknobs, light switches, toilets, faucets, and sinks. Use a mix of household bleach and water (1/3 cup bleach per gallon of water, or 4 teaspoons bleach per quart of water) or a household cleaner that’s approved to treat SARS-CoV-2. You can check the Environmental Protection Agency (EPA) website to see if yours made the list. Wear gloves when you clean and throw them away when you’re done.
There’s no proof that herbal therapies and teas can prevent infection.
COVID-19 preparation tips
In addition to practicing the prevention tips listed above, you can:
- Meet as a household or larger family to talk about who needs what.
- If you have people at a higher risk, ask their doctor what to do.
- Talk to your neighbors about emergency planning. Join your neighborhood chat group or website to stay in touch.
- Find community aid organizations that can help with health care, food delivery, and other supplies.
- Make an emergency contact list. Include family, friends, neighbors, carpool drivers, doctors, teachers, employers, and the local health department.
- Choose a room (or rooms) where you can keep someone who’s sick or who’s been exposed separate from the rest of you.
- Talk to your child’s school about keeping up with assignments.
- Set yourself up to work from home if your office is closed.
- Reach out to friends or family if you live alone. Make plans for them to check on you by phone, email, or video chat.
Can a face mask protect you from infection?
The CDC recommends that if you are not vaccinated, you should wear a cloth face mask if you go out in public. If you are at home with someone who has been infected or exposed, you should wear it as well. A mask is an added layer of protection for everyone, on top of social distancing efforts. You can spread the virus when you talk or cough, even if you don’t know that you have it or if you aren’t showing signs of infection.
The CDC advises that surgical masks and N95 masks should be reserved for health care workers and first responders.
Is it safe to travel during a pandemic?
Crowded places can raise your chances of getting COVID-19. The CDC recommends against international or cruise ship travel during the pandemic. Restrictions are being eased for those who are vaccinated, and some areas are using “vaccine passports” as a way to open up to vaccinated travelers.
A few questions may help you decide whether it’s safe to travel:
- Is the coronavirus spreading where you’re going?
- Will you have close contact with other people during the trip?
- Are you at higher risk of severe illness if you catch the virus?
- Do you live with someone who has a serious medical condition?
- Will the place where you’ll be staying be cleaned?
- Will you have access to food and other necessities?
If you choose to travel, stay away from sick people. Wash your hands often, and try not to touch your face. Wear a cloth face mask when you are around other people. All airlines require all customers to use them. They are also required on other forms of public transportation such as trains and buses.
How can you help stop the spread of the coronavirus?
Because the virus spreads from person to person, it’s important to limit your contact with other people as much as possible. and avoid large gatherings. Many states and cities have eased restrictions but this doesn’t mean the virus is gone. Continue to follow safety practices such as wearing a cloth face mask in public places and washing your hands.
While many companies continue to use work-from-home practices, that is not possible for a lot of workers. Some people work in “essential businesses” that are vital to daily life, such as health care, law enforcement, and public utilities. Everyone else should continue to limit your time in public as much as you can and wear a cloth face mask when you can’t.
The following terms have now become commonplace:
- Social distancing or physical distancing, keeping space between yourself and other people when you have to go out
- Quarantine, keeping someone home and separated from other people if they might have been exposed to the virus
- Isolation, keeping sick people away from healthy people, including using a separate “sick” bedroom and bathroom when possible
Precautions should still be followed even if you are vaccinated.
On August 23, 2021 , the FDA granted full authroization in the U.S. for the Pfizer-BioNTech COVID-19 vaccine for use in those 16 years and older. The mve come eight months after granting an emergency use authorization (EUA). At present an EUA allowing the Pfizer vaccine in those 12 to 15 is still in use. In addition, the CDC’s Advisory Committee on Immunization Practices (ACIP). FDA is looking at the possible authorization of a booster dose of the vaccine to help combat highly contageous variants.
EUAs are also in place for vaccines developed by Moderna and Johnson & Johnson.
Both the Pfizer and Moderna vaccines require two doses, taken a few weeks apart while J & J is just one shot. Health care workers and the elderly were originally given priority in receiving the vaccines but by May 2021, the vaccines were made available to anyone.
These vaccines were developed at an unprecedented speed, with testing in humans starting in March 2020. The FDA says that no corners were cut to allow for approval and that the innoculations are safe. The CDC has said it is safe for pregnant women and there's no evidence that antibodies formed from COVID-19 vaccination cause any problem with pregnancy,.
Clinical trials for other vaccines are still underway. If you're interested in volunteering for a COVID-19 vaccine trial, here are some sources of more information:
COVID-19 Prevention Network (CoVPN). This is funded by the National Institute of Allergy and Infectious Diseases and coordinated by the Fred Hutchinson Cancer Research Center in Seattle. Its goal is to enroll thousands of volunteers into COVID vaccine trials nationwide. Many research centers are using this site to find volunteers.
Sites that link volunteers with trials nationwide include:
Individual hospitals, universities, research centers, and others may also provide opportunities to enroll in a COVID-19 vaccine clinical trial. Some include:
SAResearch (Clinical Trials of Texas)
You can also call or visit the website of your local hospital or research institution to find out if they are taking part in any trials.
There’s no specific treatment for COVID-19. People who get a mild case need care to ease their symptoms, like rest, fluids, and fever control. Take over-the-counter medicine for a sore throat, body aches, and fever. But don't give aspirin to children or teens younger than 19.
You might have heard that you shouldn't take ibuprofen to treat COVID-19 symptoms. But the National Institutes of Health says people who have the virus can use nonsteroidal anti-inflammatory drugs (NSAIDs) or acetaminophen as usual.
Antibiotics won’t help because they treat bacteria, not viruses. If you hear about people with COVID-19 getting antibiotics, it’s for an infection that came along with the disease.
People with severe symptoms need to be cared for in the hospital.
The antiviral medication called remdesivir (Veklury) is the first medication to get FDA approval for treatment of patients hospitalized with COVID-19. Originally developed to treat Ebola, evidence shows that those treated with remdesivir recovered in about 11 days compared to 15 days for those treated with a placebo.
Many clinical trials are under way to explore treatments used for other conditions that could fight COVID-19 and to develop new ones.
For instance, trials are under way for tocilizumab, another medication used to treat autoimmune conditions. And the FDA is also allowing clinical trials and hospital use of blood plasma from people who’ve had COVID-19 and recovered to help others build immunity. You’ll hear this called convalescent plasma. Currently, evidence of its effectiveness is limited.
Early in the pandemic, the antimalarial drugs hydroxychloroquine and chloroquine were considered as possible treatments. The FDA later rescinded an emergency use order because studies found that the drugs were ineffective and the risks outweighed the benefits.
A variety of steroid medications are being used including dexamethasone which is used to treat conditions such as arthritis, blood/hormone/immune system disorders, allergic reactions,. More studies on effectiveness are still being conducted.
Is there a cure for the new coronavirus?
There’s no cure yet, but researchers are working hard to find one.
Every case is different. You may have mild flu-like symptoms for a few days after exposure, then get better. But some cases can be severe or fatal.
Symptoms can also linger for weeks, even if they’re mild.
More than a third of people older than 18 who have signs of the virus aren’t totally recovered 2 or 3 weeks later, according to a CDC survey. Fatigue and cough were the symptoms that were most likely to linger.
Some other people who’ve had COVID-19 develop a condition similar to myalgic encephalomyelitis, also known as chronic fatigue syndrome. They may have a brain fog, severe fatigue, pain, trouble thinking, or dizziness.
What is the recovery rate for coronavirus?
Scientists and researchers are constantly tracking COVID-19 infections and recoveries. But they don’t have information about the outcome of every infection. Early estimates predict that the overall COVID-19 recovery rate will be between 97% and 99.75%.
There have been a few cases of reinfection reported and presently, it is considered a rare occurrence. With other coronaviruses that only cause colds, you have a period that you’re immune, but that goes away over time. That also appears to be the case with this coronavirus. Immunity is estimated to last at least three to four months.
Are coronaviruses new?
Coronaviruses were first identified in the 1960s. Almost everyone gets a coronavirus infection at least once in their life, most likely as a young child. In the United States, regular coronaviruses are more common in the fall and winter, but anyone can come down with a coronavirus infection at any time.
The symptoms of most coronaviruses are similar to any other upper respiratory infection, including a runny nose, coughing, sore throat, and sometimes a fever. In most cases, you won't know whether you have a coronavirus or a different cold-causing virus, such as a rhinovirus. You treat this kind of coronavirus infection the same way you treat a cold.
Have there been other serious coronavirus outbreaks?
Coronaviruses have led to two serious outbreaks:
- Middle East respiratory syndrome (MERS). About 858 people have died from MERS, which first appeared in Saudi Arabia and then in other countries in the Middle East, Africa, Asia, and Europe. In April 2014, the first American was hospitalized for MERS in Indiana, and another case was reported in Florida. Both had just returned from Saudi Arabia. In May 2015, there was an outbreak of MERS in South Korea, which was the largest outbreak outside of the Arabian Peninsula.
- Severe acute respiratory syndrome (SARS). In 2003, 774 people died from an outbreak. As of 2015, there were no further reports of cases of SARS.