11 Surprising Facts About Coronavirus

  • senior man with face mask looking through window
    COVID-19 Facts That Might Surprise You
    It has been more than 17 months since the novel coronavirus, SARS-CoV-2, caused an outbreak of respiratory disease (COVID-19) and pneumonia in Wuhan, China. Since then, SARS-CoV-2 has spread around the world, sickening more than 161 million people. 

    By now, you probably know more about viruses than you ever wanted to. But we are still learning more every day. Find out what doctors know about SARS-CoV-2 and the disease it causes, COVID-19, including the strange array of symptoms and how it's treated.

  • senior woman smelling coffee or tea cup
    1. Anosmia (loss of smell) is a symptom.
    The most commonly reported symptoms of COVID-19 include fever, cough and shortness of breath. However, as the disease has spread around the world, healthcare providers have noticed a few unusual symptoms, including loss of smell (anosmia) and decreased sense of taste (ageusia).

    In South Korea, 30% of people who tested positive for the virus said that loss of smell was their first major symptom. In Germany, more than 2 out of 3 confirmed cases included loss of smell and taste.

    Doctors recommend that anyone who experiences a sudden loss of smell or taste self-isolate and contact their healthcare provider.

  • Transmission electron microscope image of SARS-CoV-2—the coronavirus that causes COVID-19—emerging from the surface of cells cultured in the lab. Credit: National Institute of Allergy and Infectious Diseases-Rocky Mountain Laboratories, NIH
    2. SARS-CoV-2 binds tightly to human cells.
    In 2003, SARS, or severe acute respiratory syndrome, spread from Asia throughout the world, sickening more than 8,000 people and killing more than 700 over a six-month period. The virus that caused SARS (SARS-CoV) is similar to the one that causes COVID-19—both are types of coronaviruses—but researchers have recently discovered an important difference that may explain why the new coronavirus is so hard to stop: SARS-CoV-2 (the virus that causes COVID-19) binds 10 to 20 times more tightly to human cells than SARS-CoV (the virus responsible for SARS).

  • mother taking temperature of her crying baby
    3. Coronavirus can make babies seriously ill.
    Compared to adults, children appear much less likely to get sick if they contract the novel coronavirus. However, the very young (less than 1 year) appear to be more vulnerable to serious illness than older children. From the records of 2,143 Chinese children, nearly 11% of sick infants were seriously or critically ill, compared to 7% of children ages 1 to 5 years, 4% of children ages 6 to 15 and 3% of teenagers aged 16 and older. In the United States, from February 12 to April 2, less than 2% of cases were in children younger than 18 years. Of these pediatric cases, 15% were in children under 12 months.

    A multisystem inflammatory syndrome (MIS) is affecting some children positive for current or recent SARS-CoV-2 infection. MIS is rare but very serious. MIS is characterized by gastrointestinal symptoms and cardiac (or other system) inflammation. The syndrome is similar to Kawasaki disease, an illness that could lead to enlarged coronary arteries or even coronary artery aneurysms. Contact your doctor right away if your child has fever, abdominal pain, vomiting, diarrhea, neck pain, rash, bloodshot eyes, and/or is much more tired than usual. (Not all children will experience all MIS symptoms.)

  • outstretched hand touching elevator button
    4. The COVID-19 virus can live on surfaces for days.
    COVID-19 is spread primarily through respiratory droplets. When an infected person sneezes or coughs, the virus can travel from one person to another, either directly (which is why the CDC recommends maintaining at least a 6-foot distance from other people) or via an intermediate surface. The virus can also spread through the air, but this is more likely in crowded, indoor areas with poor ventilation than in areas with plenty of outdoor air and fewer people.

    Researchers have found that the virus can live up to 24 hours on cardboard and 2 to 3 days on plastic and stainless steel. The CDC reports that the virus was detected on surfaces of the Diamond Princess cruise ship up to 17 days after passengers disembarked. However, only pieces of the virus were detectable, not viruses capable of infecting a person.

  • Passengers move through crowded airport
    5. People who don’t have symptoms can spread the virus.
    One-third of 565 Japanese citizens who were evacuated from Wuhan, China in February that tested positive for coronavirus infection never developed COVID-19 symptoms; and a study out of China reports more than half of infected children had no symptoms or only mild symptoms. The CDC estimates up to 40% of infected individuals do not experience symptoms.

    That’s good news for the affected individuals, but bad news for public health because people who are infected but don’t have symptoms can unintentionally spread the virus to others. Public health officials are asking all people to dramatically limit social contact to prevent the spread of disease. Wearing a cloth facial covering when you go to a public indoor place protects others because you could be infected and not know it. Wearing a mask reduces the risk of unknowingly spreading the virus to others in the space around you.

  • scientist or lab technician wearing safety glasses and gloves while holding test tube of blood sample
    6. People with type A blood may be more susceptible to infection.
    A Chinese study of 2,173 individuals who were hospitalized with COVID-19 found that the proportion of sick people with type A blood was significantly greater than researchers would expect based upon the percentage of people with type A blood in the general population. The study also found that there were fewer sick people with type O blood than would be expected.

    Genomic studies of patient from Italy and Spain have supported these findings, showing a higher risk of developing COVID-19 respiratory failure in patients with type A blood.

  • man with cough in pharmacy looking for medicine
    7. You may already have been infected.
    Some people—about 20% of infected individuals—never develop symptoms. And some people who had what they thought was a “bad cold” or the flu may have actually had COVID-19.

    Scientists developed tests that can detect SARS-CoV-2 antibodies in the blood, which is evidence of past infection with the virus. Such tests may help us eventually understand the true extent of this pandemic. Contact your doctor or public health department about antibody testing if you think you had the infection. The CDC recommends virus testing for active infection for anyone who may have been exposed to a confirmed case of COVID-19, even if there are no symptoms.

  • woman with tummy ache and toilet paper
    8. Some people with COVID-19 have digestive symptoms.
    Cough, fever and shortness of breath are the most common symptoms of novel coronavirus infection, but many people also experience digestive symptoms, including lack of appetite, diarrhea, vomiting and abdominal pain. According to study published in The American Journal of Gastroenterology, 48.5% of 204 people admitted to the hospital with COVID-19 had digestive symptoms. A small percentage (7 people) only had digestive symptoms; these individuals did not have a cough, fever or shortness of breath.

  • gettyimages 1134952868
    9. Reinfection may be possible.
    If a person gets COVID-19, are they immune to future infection from SARS-CoV-2? And how long will immunity last? Ten to 30% of our common colds are caused by four different coronaviruses, and we all know that having a cold doesn’t keep you from catching another cold.

    Across several countries, doctors have confirmed less than a 100 cases of SARS-CoV-2 reinfection. The risk of reinfection with SARS-CoV-2 varies from person to person and also depends on the specific strain, or variant of SARS-CoV-2 the person is exposed to. In general, natural immunity and protection from reinfection is thought to last 6 to 12 months, but some people were reinfected earlier.

  • hands of researcher in medical lab
    10. The FDA has approved the first targeted COVID-19 treatment.
    A COVID-specific drug, bamlanivimab, has emergency use authorization (EUA). It is for people with mild-to-moderate COVID-19 at high risk for developing severe disease. In clinical trials, the drug—a monoclonal antibody that targets the SARS-CoV-2 spike protein—reduces emergency room visits and hospitalizations. The U.S. FDA (Food and Drug Administration) also authorized the antibody cocktail former President Trump received when he developed COVID-19 in October 2020.

    Remdesivir (Veklury) is an antiviral medicine approved by the FDA to treat COVID-19, but it is reserved for hospitalized patients. It has been shown to improve symptoms and shorten recovery time in some cases.

    More treatments are in clinical trials.
  • Covid-19 vaccine vials in a row macro close up
    11. Vaccination is 100% effective in preventing severe COVID-19.
    There are also three new vaccines that provide immunity to COVID-19. All three vaccines are 100% effective in preventing severe COVID-19. The first two vaccines (Pfizer-BioNTech and Moderna so-called "mRNA" vaccines) are 90% effective in preventing infection and symptoms, and the third vaccine (Johnson & Johnson's vector vaccine) is 76% effective, but still well above the 50% threshold of effectiveness. The Johnson & Johnson (J&J) vaccine trial was underway at a time when more powerful virus strains were circulating in the community, which could have made the vaccine less effective. The J&J vaccine is still 100% protective against severe disease caused by one of the most concerning variants—the B.1.351 from South Africa.
11 Surprising Facts About Coronavirus | COVID-19 Facts

About The Author

Jennifer L.W. Fink, RN, BSN is a Registered Nurse-turned-writer. She’s also the creator of BuildingBoys.net and co-creator/co-host of the podcast On Boys: Real Talk about Parenting, Teaching & Reaching Tomorrow’s Men.
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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Jun 16
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