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Here’s what you need to know about the coronavirus responsible for causing COVID-19

  • Coronaviruses comprise a large family of viruses, some of which cause respiratory illnesses in humans, ranging from common colds to more severe conditions such as Severe Acute Respiratory Syndrome (SARS) and Middle Eastern Respiratory Syndrome (MERS).

    They derive their name from the fact that under electron microscopic examination, each virion is surrounded by a “corona,” or halo. This is due to the presence of protein spikes emanating from the exterior of the virus.2 

    A 'novel coronavirus' is a new, previously unidentified strain of coronavirus. The novel coronavirus involved in the outbreak that began in 2019 has been named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).3 

    The disease it causes has been named “coronavirus disease 2019” or “COVID-19.”3  

  • COVID-19 can spread from person to person usually through close contact with an infected person or through respiratory droplets that are dispersed into the air when an infected person coughs, sneezes, talks, or sings.4

    Droplets can land in the mouths or noses of people who may be close by. Spread is more likely when people are within 6 feet of each other.4

    Some variants of the virus may spread faster and cause more infections than earlier forms of the virus that causes COVID-19.4

  • As of November 11, 2021, 225 countries and territories reported about 251 million COVID‑19 cases and over 5 million deaths since China reported its first cases to the World Health Organization (WHO) in December of 2019.5

  • People with COVID-19 may have symptoms that range from mild symptoms to severe illness. Symptoms may appear 2-14 days after exposure to the virus.6   

    Some may be asymptomatic, but for those who do become symptomatic, the most common symptoms of COVID-19 include:6 

    • Fever or chills
    • Cough
    • Shortness of breath or difficulty breathing
    • Fatigue
    • Muscle or body aches
    • Headache
    • New loss of taste or smell
    • Sore throat
    • Congestion or runny nose 
    • Nausea or vomiting
    • Diarrhea

    This list does not include all possible symptoms

  • The best way to protect others and yourself is by getting fully vaccinated and maintaining social distancing and good hygiene.7

    Since some infected persons may not yet be exhibiting symptoms or their symptoms may be mild, maintaining a physical distance (2 meters or 6 feet) with those outside your household is a good idea.7

    To help prevent getting COVID-19:7

    • Wash your hands often with soap and water for at least 20 seconds especially after you have been in a public place, or after blowing your nose, coughing, or sneezing. 
    • Cover your mouth and nose with a mask or cloth face cover when around others at all times. 
    • Cover coughs and sneezes with a tissue or use the inside of your elbow. 
    • Clean and disinfect frequently touched surfaces daily. This includes tables, doorknobs, light switches, countertops, handles, desks, phones, keyboards, toilets, faucets, and sinks. 
    • Monitor your health daily and follow CDC guidance if symptoms develop. 
  • If you have a fever, cough, or other symptoms, you might have COVID-19. 

    Most people have mild illness and are able to recover at home. If you think you may have been exposed to COVID-19, contact your healthcare provider. 

    If you are sick, keep track of your symptoms. If you have an emergency warning sign (including trouble breathing), get emergency medical care immediately.

Learn more about the process of joining a clinical trial and find a trial near you.

Go to Pfizer Clinical Trials Site

1 Human Coronavirus Types. Centers for Disease Control and Prevention.

2 Middle East Respiratory Syndrome (MERS). Centers for Disease Control and Prevention. Accessed 26 Aug. 2021  

Naming the coronavirus disease (COVID-19) and the virus that causes it. WHO. Accessed October 25. 2021. 

4. How COVID-19 Spreads. Centers for Disease Control and Prevention. Accessed October 25, 2021.  

5 WHO Coronavirus (COVID-19) Dashboard. WHO. Accessed October 25, 2021. 

Symptoms of COVID-19. The Centers for Disease Control and Prevention. Accessed October 26, 2021. 

7 How to Protect Yourself & Others. The Centers for Disease Control and Prevention. October 26, 2021. 

8 What to Do If You Are Sick. The Centers for Disease Control and Prevention. Accessed October 26, 2021.