10 Things to Know About Coronavirus

Medically Reviewed By William C. Lloyd III, MD, FACS
illustration of coronavirus, image credit Alissa Eckert and Dan Higgins from the Centers for Disease Control and Prevention
Alissa Eckert, MS; Dan Higgins, MAM

The first diagnosis of the respiratory disease caused by the novel (new) coronavirus was in Wuhan in Hubei Province, China in December of 2019. Since the World Health Organization declared a pandemic on March 11, 2020, the number of confirmed cases has topped 270 million, including 50 million cases in the United States. (Image credit: illustration of coronavirus, Alissa Eckert and Dan Higgins from the U.S. Centers for Disease Control and Prevention.)

For the most current data and prevention guidance, contact your state's health department, visit the CDC website Trusted Source Centers for Disease Control and Prevention (CDC) Governmental authority Go to source , or refer to this list of CDC and other resources.

Here’s what you need to know about the novel coronavirus:

1. The novel coronavirus is SARS-CoV-2 and the disease is COVID-19.

SARS-CoV-2 stands for Severe Acute Respiratory Syndrome-Coronavirus-2, because the virus is very similar to the SARS coronavirus first discovered in 2003. The SARS-CoV-2 disease is COVID-19, for Coronavirus Disease 2019.

2. The first cases in the United States were mainly in people who traveled from China.

Some of the first known cases of COVID-19 in the United States were in people returning from travel abroad, from China, cruise ships, and subsequently from other countries with COVID-19 spread. These are so-called “imported” cases. On February 25, 2020, the CDC diagnosed the new coronavirus disease in a person who lives in California but who had no known travel history or close contact with an infected person. This is known as "community" spread because the case did not arise from a known source. 

3. The novel coronavirus spreads very easily from person to person.

SARS-CoV-2 spreads through tiny respiratory droplets from the nose or mouth when an infected person coughs or sneezes. You can contract the coronavirus if these droplets land in your nose or mouth, you inhale them, or you touch a contaminated surface or object and then touch your nose or mouth before washing your hands. The virus also spreads through the air, particularly in enclosed spaces with poor ventilation.

Infected people are contagious before symptoms develop. That is presymptomatic transmission. Studies show the virus multiplies fast in the nose and throat, even in the beginning of an infection when the person does not yet feel ill. Infectious disease experts estimate about 40% of infected people never develop symptoms. Asymptomatic (and presymptomatic) individuals still shed the virus and are capable of infecting others.

4. Social distancing and wearing a mask helps slow the spread of infection.

Avoiding large public gatherings and keeping a distance of at least 6 feet from other people slows virus transmission. Because the virus can spread through the air in poorly ventilated, crowded spaces, you should avoid indoor public spaces to limit possible exposure. Wearing a cloth or disposable surgical mask over your mouth and nose helps limit the amount of respiratory droplets you release into the environment when you talk, sneeze and cough. A mask also offers some protection to the wearer.

Everyone wearing a mask in indoor public spaces is crucial because you could be infected and not know it; wearing a mask reduces the chance of unknowingly spreading the virus to others. Masks are also important outside if you cannot maintain a social distance of at least 6 feet from others. If you are vaccinated against COVID-19, you are less likely to contract the virus and spread it if you do become infected; but, wearing a mask in indoor, public spaces provides additional protection.

5. COVID-19 symptoms range from mild to severe and it can be fatal.

For some patients, coronavirus symptoms mimic those of the common cold, while others experience the same symptoms that accompany a severe respiratory infection or worse. COVID-19 symptoms include fever, cough, body aches, sore throat, fatigue, phlegm/sputum production, loss of sense of smell, and shortness of breath. In some cases, the virus attacks the lungs and symptoms are severe enough the patient requires hospital care with supplemental oxygen and fluids, even breathing support with a ventilator. COVID-19 symptoms appear 2 to 14 days after exposure.

The risk of dying from COVID-19 is greater in people who have underlying chronic health conditions, such as obesity and/or heart, lung or liver disease.

6. COVID-19 treatment includes FDA-approved antivirals and antibodies.

The FDA (Food and Drug Administration) approved the antiviral drug, remdesivir (Veklury), for use in hospitalized COVID-19 patients. It has been shown to speed up recovery time in clinical studies.

The FDA also approved the first targeted COVID-19 treatment, a monoclonal antibody (Mab) called bamlanivimab, for patients with mild-to-moderate COVID-19 at risk for severe disease. The drug is specific for the virus's spike protein, interfering with how the virus infects cells. The Mab cocktail former President Trump received has also been approved for high-risk patients with mild-to-moderate COVID-19.

The FDA is reviewing data on an oral medication for COVID-19, and may authorize it for people infected with SARS-CoV-2 and with risk factors for severe disease. It would be the first targeted COVID-19 medication you can take by mouth rather than infusion.

In the meantime, hospitalized patients receive appropriate treatment for serious respiratory symptoms and other disease complications. The death rate of COVID-19 has decreased significantly since the pandemic first started, largely because doctors worldwide are learning more about the disease and when to deliver specific treatments.

7. There are three authorized or approved COVID-19 vaccines.

All three vaccines are highly effective in preventing severe and life-threatening cases of COVID-19, including cases caused by variants of the virus. The COVID-19 vaccine from Pfizer-BioNTech is authorized for people ages 5 and older and approved for ages 18 and older. The vaccines from Moderna and Janssen (a Johnson & Johnson company) are authorized for people ages 18 and older. The vaccine is free to anyone who is eligible to receive it.

8. The source of the novel coronavirus is linked to animals.

The 2019 coronavirus is thought to have spread directly from animals to humans. Once in humans, the virus was able to spread person to person. This is similar to the spread of two other coronaviruses that originated from animals: SARS-CoV (civet cats) and MERS-CoV (camels). There are many different coronaviruses. They mainly infect animals, but some of the viruses can spread from animals to humans. This is the case with SARS-CoV, MERS-CoV, and the new coronavirus (SARS-CoV-2): All three viruses came from bats.

9. The novel coronavirus is mutating.

Variations, or mutations in SARS-CoV-2 are occurring all the time, as the virus passes from person to person. This is normal for coronaviruses and many other viruses. In most cases, mutations have little effect. In others, they can have a dramatic effect, like the variant first discovered in the United Kingdom and the Delta variant. The Delta variant is twice as contagious as the original virus that started the pandemic. Omicron is the latest variant of concern.

10. Get tested for COVID-19 if you have symptoms.

If you have symptoms of COVID-19, get tested for the virus. As you wait for test results, stay away from others. If you test positive, continue your isolation until you are no longer contagious, which is about 10 days after you first notice symptoms. If you don't have symptoms, wait 10 days after your first positive virus RNA test.

Keep in mind there is an incubation period for the virus. Even if you contract the virus, your COVID test will be negative until you have enough virus to be detected (regardless of symptoms). It's best to wait about five days from the time of close contact to take the test. If possible, stay home and avoid in-person contact (quarantine), while monitoring yourself daily for signs and symptoms of COVID-19. Call your healthcare provider if you develop serious symptoms, including difficulty breathing. (If your test is negative, you may end quarantine after 7 days, as long as you did not develop COVID symptoms during quarantine.)

For the most recent information about COVID-19, check the CDC website for updates Trusted Source Centers for Disease Control and Prevention (CDC) Governmental authority Go to source , including the number of confirmed cases and advice for travelers. Call your state's public health department for local information. Some states have set up phone hotlines. 

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Apr 26
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