Find answers to frequently asked questions about COVID-19, including how the virus is spread, risk factors for severe disease, and information on new monoclonal antibody treatments.

Coronavirus and COVID-19 are not the same thing, but sometimes these terms are used interchangeably. Coronaviruses are a family of viruses that have crown-like spikes on their surface. The scientific name for the new coronavirus that emerged from China in December 2019 is SARS-CoV-2, which stands for severe acute respiratory syndrome coronavirus 2.

COVID-19 is the disease caused by the new SARS-CoV-2 virus and stands for coronavirus disease 2019.

Fever, aches, and a cough are symptoms commonly found in patients with either COVID-19 or the flu. Both diseases can range in severity from mild to severe and may lead to the development of pneumonia. Although both viruses may be fatal, COVID-19 is associated with a significantly higher mortality rate than the flu. Estimates vary, but approximately 1% to 3% of people with COVID-19 will die from the disease.

There are several reasons why the coronavirus is more dangerous than the flu:

  • Coronavirus is twice as contagious as the flu. Research indicates that a person with the flu infects an average of 1.28 other people. However, a person with coronavirus can infect between 2 to 3 other people.
  • Coronavirus has a longer incubation period. The incubation period is the time between exposure to the virus and the onset of symptoms. People with coronavirus might not have symptoms for up to 14 days, and some may not develop symptoms at all. People with the flu usually develop symptoms within 2 days of infection. Since coronavirus has a significantly longer incubation period, infected individuals may unknowingly spread the virus for a longer period of time.
  • There is an effective vaccine available for the flu. There is no vaccine available for COVID-19, but development and testing are in progress.

People aged 65 years and older and people of any age with serious underlying medical conditions may be at higher risk of severe illness from COVID-19.1 Preexisting medical conditions that increase the risk of serious illness include1,2:

  • Chronic lung disease or moderate-to-severe asthma
  • Cardiovascular disease, hypertension (high blood pressure), and serious heart conditions
  • Diabetes
  • Liver disease
  • Cancer
  • Chronic kidney disease and dialysis
  • Obesity
  • Immunosuppression (bone-marrow or organ transplantation, immune deficiencies, autoimmune diseases, poorly controlled HIV or AIDS, or long-term use of corticosteroids)

People who are at high risk of serious illness with COVID-19 should continue to wear face masks, practice social distancing, and use good hand hygiene to minimize their chance of contracting the virus that causes COVID-19.3

Other high-risk factors can be found on the CDC website at www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-medical-conditions.html

Antibodies are proteins created by your immune system to fight infection. Antibodies bind specifically to viruses and other microbes and target them for destruction by immune cells. Monoclonal antibodies have a similar structure to the antibodies created naturally by your immune system, but they are created in a laboratory. Monoclonal antibodies bind to the SARS-CoV-2 virus that causes COVID-19 and decrease the viral load (ie, number of viruses) in the body. Reducing the viral load means you may have milder symptoms and are less likely to be hospitalized with COVID-19.1,4

Monoclonal antibodies may help people who1,4:

  • Have mild-to-moderate COVID-19, and
  • Have had symptoms for 10 days or less, and
  • Are at high risk of developing severe COVID-19

Monoclonal antibodies may also be used to prevent infection in patients who are exposed to the virus. If you have had close contact with someone who has COVID-19, monoclonal antibodies given soon after exposure can reduce your risk of getting sick. Speak with your healthcare provider as soon as possible to see if you are eligible for monoclonal antibody therapy.

Use the Monoclonal Antibody Eligibility Tool to find out if you (or someone you know) are a candidate for this treatment.

Monoclonal Antibody Eligibility Tool_Patient_FINAL

The new coronavirus is spread through respiratory droplets released into the air when an infected person coughs, sneezes, or talks. These droplets generally do not travel more than a few feet before falling to the ground. If you are in close proximity to someone who is infected, you may inhale the virus.

Coronavirus can also be transmitted from objects and surfaces that are contaminated with the virus. Studies suggest that the virus can live on surfaces for a few hours or up to several days, depending on the surface and environmental factors. A small amount of virus can be found on plastic for up to 3 days, on stainless steel for up to 2 days, and for up to one day on cardboard. It is important to practice good hand hygiene to minimize the risk of infection. It is recommended that you wash your hands for 20 seconds with soap and water or use an alcohol-based hand sanitizer that contains at least 60% alcohol to prevent the spread of the virus.

Symptoms could appear as soon as 2 days or as late as 14 days after exposure to the virus. The median time for symptoms to develop is about 5 days.1,2 If you believe you have been exposed to the virus that causes COVID-19, it is important to quarantine for 14 days to prevent the spread of the virus to others.3

It is estimated that on average people with COVID-19 first develop symptoms approximately 5 days after exposure to the virus. However, symptoms may develop between 2 and 14 days after exposure.1,2 One study found that people with COVID-19 were contagious approximately 2 to 3 days before symptom onset and were most infectious the day before symptoms appeared.

People infected with the new coronavirus can be contagious without symptoms.2 It is estimated that up to 50% of people infected with coronavirus remain asymptomatic. However, these people are still contagious. One study found that people with no symptoms were the source of 44% of diagnosed COVID-19 cases.

There are 3 available and recommended COVID-19 vaccines in the United States. All currently available vaccines are safe and effective in preventing COVID-19. You should get the first vaccine that is available to you. Do not wait for a specific brand.5


People with moderately to severely compromised immune systems are especially vulnerable to COVID-19 and may not build enough immunity in response to 2 vaccine doses. These individuals should receive an additional dose of the Pfizer-BioNTech or Moderna vaccine at least 28 days after their second vaccine dose.9

Protection against the virus may decrease over time, and booster shots are recommended.  Booster shots are available for individuals who are 65 years or older or aged 18+ with underlying medical conditions or who live or work in high-risk settings.6

Vaccines for COVID-19 contain a small piece of the virus’ genetic material and do not contain the full virus. You cannot get COVID-19 from a vaccine.5

The genetic material in a vaccine allows our immune system to recognize the virus and produce long-lasting memory cells that fight future infections without ever getting the illness. It typically takes two weeks for your body to produce memory cells.5 Therefore, if you get infected with the virus that causes COVID-19 before or shortly after vaccination, you may get sick because your body did not have enough time to create memory cells against the virus.5

You may experience side effects after receiving a COVID-19 vaccine. Symptoms, such as fever, sore arm, chills, and fatigue, are normal and are signs the body is building immunity against the virus.5,7

Coronaviruses are a family of viruses that have crown-like spikes on their surface. The scientific name for the new coronavirus that emerged from China in December 2019 is SARS-CoV-2, which stands for severe acute respiratory syndrome coronavirus 2.1

COVID-19 is the disease caused by the new SARS-CoV-2 virus and stands for coronavirus disease 2019.

Some patients report long-lasting symptoms after recovering from COVID-19. Although these patients no longer have an active infection, they still experience complex symptoms caused by the virus weeks or sometime months after diagnosis. Persistent symptoms can happen to any one who has had COVID-19, even if their illness was mild or they had no symptoms.8

Commonly reported lingering health issues from COVID-19 include8:

  • Fatigue
  • Shortness of breath
  • Anxiety
  • Persistent cough
  • Racing heartbeat
  • “Brain fog” or problems with memory or concentration
  • Depression
  • Joint pain
  • Muscle aches
  • Dizziness
  • Rashes
  • Vision changes
  • Loss of smell or taste

A serologic test is a blood test that identifies antibodies against SARS-CoV-2, the virus that causes COVID-19. Antibodies are proteins created by your immune system to fight infections. Since it takes your body 5 to 10 days to produce enough antibodies to be detected in a test, serologic tests cannot be used to diagnose an active COVID-19 infection, even in patients with severe disease.

Serologic tests can be used to identify people who have been infected with the new coronavirus during the course of the pandemic. However, since the coronavirus that causes COVID-19 is new, there is still much we do not know about it. Scientists are working to determine if antibodies against SARS-CoV-2 provide protection against future infections by this virus. If antibodies do provide immunity, we do not know what amount, or titer, of antibodies would provide protection or for how long this protection would last.

There are currently no approved agents for the treatment or prevention of COVID-19.

In late April, the FDA issued a warning against the use of the anti-malarial medications hydroxychloroquine and chloroquine in patients not enrolled in clinical trials. Several studies have shown that these medications do not decrease the risk of death from COVID-19 and may increase the risk of life-threatening heart rhythms.

One clinical trial found that patients with COVID-19 who received remdesivir, an antiviral drug, recovered faster than patients who received a placebo. Several other drugs are also under investigation for the management of COVID-19. However, it may take up to a year before any drugs for the treatment of COVID-19 are available to the general public. Clinical trials must be performed to ensure that new medications are safe and effective and to determine what the proper dosage should be.

Some doctors in France advise people against using ibuprofen (i.e., Advil®, Motrin®) to manage the symptoms of COVID-19. There were several reports of healthy patients with COVID-19 who were taking ibuprofen and developed severe disease, particularly pneumonia. However, there were no scientific studies to support this advice.

The World Health Organization (WHO) initially recommended using acetaminophen (i.e., Tylenol®) instead of ibuprofen to reduce the fever, aches, and pains related to coronavirus infection. However, the WHO now states that either acetaminophen or ibuprofen can be used. It is important to make sure that you do not exceed the maximum daily dose of 3,000 milligrams of acetaminophen per day.


  1. National Institutes of Health (NIH). Coronavirus disease 2019 (COVID-19) treatment guidelines. Updated 10/19/2021. (https://files.covid19treatmentguidelines.nih.gov/guidelines/covid19treatmentguidelines.pdf). Accessed 10/20/2021.
  2. Centers for Disease Control and Prevention (CDC). Interim clinical guidance for management of patients with confirmed coronavirus disease (COVID-19) (www.cdc.gov/coronavirus/2019-ncov/hcp/clinical-guidance-management-patients.html). Accessed 10/20/2021.
  3. World Health Organization (WHO). Q&A on coronaviruses (COVID-19) (www.who.int/emergencies/diseases/novel-coronavirus-2019/question-and-answers-hub/q-a-detail/q-a-coronaviruses). Accessed 10/20/2021.
  4. Department of Health and Human Services (HHS). CombatCOVID (https://combatcovid.hhs.gov/i-have-covid-19-now/monoclonal-antibodies-high-risk-covid-19-positive-patients?gclid=Cj0KCQiA-aGCBhCwARIsAHDl5x91slr99GiHMDTqGgA4UHr0yP-GAg4UIK-r27qBOnA0gRdXZv9S00AaAqltEALw_wcB). Accessed 10/20/2021.  
  5. CDC. Different COVID-19 vaccines. Updated 9/1/2021. (www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines.html). Accessed 10/20/2021.
  6. CDC. Who is eligible for a COVID-19 vaccine booster shot? Updated 10/7/2021.  (www.cdc.gov/coronavirus/2019-ncov/vaccines/booster-shot.html) Accessed 10/20/2021.  
  7. CDC. What to expect after getting a COVID-19 vaccine. (www.cdc.gov/coronavirus/2019-ncov/downloads/vaccines/324160-A-COVID-19_VaccinationPoster_WhatToExpect_LTR-6.24.pdf) Accessed 10/20/2021.
  8. CDC. Post-COVID conditions. Updated 9/16/2021. (www.cdc.gov/coronavirus/2019-ncov/long-term-effects.html). Accessed 10/20/2021.
  9. CDC. COVID-19 vaccines for moderately to severely immunocompromised people. Updated 10/18/2021. (www.cdc.gov/coronavirus/2019-ncov/vaccines/recommendations/immuno.html). Accessed 10/20/2021/