How Does COVID-19 Mainly Spread
COVID-19 mainly spreads via airborne particles and respiratory droplets formed when an infected person breathes, talks, coughs, or sneezes

COVID-19 mainly spreads via airborne particles and respiratory droplets formed when an infected person breathes, talks, coughs, or sneezes. These particles and droplets contain the SARS-CoV-2 virus that causes COVID-19. Exposure and risk of transmission increases if the infected person is within 3-5 feet of other people.

Respiratory droplets and aerosols range in size from visible to microscopic. Droplets can fall to earth quickly, but aerosols can stay in the air for a longer period and travel long distances. Once exhaled by the infected person, they can be inhaled by another person. In closed spaces or indoors, the droplets or aerosols remain suspended in the air or can settle on the surfaces and are more likely to spread faster among people there. 

Transmission of COVID-19 can also occur at distances greater than 6 feet. Particles released from an infected person can remain suspended in the air even after the person has left the indoor space and infect other people.

An infected person continues to shed the virus even after symptoms go away, which could be as long as 20 days.

How long can the SARS-CoV-2 virus survive on surfaces?

The SARS-CoV-2 virus can survive on surfaces for 4-72 hours. These contaminated surfaces are referred to as fomites and include:

  • Countertops
  • Handrails
  • Doorknobs
  • Light switches
  • Smartphones
  • Clothing

Fomites are considered an indirect method of human-to-human transmission. Transmission of the virus occurs when a person touches a contaminated surface and then touches their face.

Can COVID-19 spread through other body fluids?

According to some studies, the SARS-CoV-2 virus can live in the digestive system, suggesting that sharing toilets may also carry the risk of virus transmission. A study published in the journal Emerging Microbes & Infections (2020) found that virus stayed in feces and in tissue collected from the anus up to 4 weeks even after COVID-19 symptoms were gone.

Other studies have detected the SARS-CoV-2 virus in other bodily fluids such as saliva, urine, semen, and tears, although there is limited data regarding this. The presence of the virus in semen suggests that the COVID-19 can be sexually transmitted.

Can a pregnant woman transmit COVID-19 to her baby?

There is mixed evidence regarding COVID-19 transmission from mothers to babies. Some studies have shown newborns testing positive for SARS-CoV-2 36 hours after birth. Transmission from mother to child is rare but still possible according to studies.

What are the symptoms of COVID-19?

COVID-19 typically causes flu-like respiratory symptoms that can range from a cough to pneumonia. Common symptoms include:

Most people with COVID-19 have mild symptoms. Some may show no symptoms at all, and some may have severe symptoms. Older adults and people with underlying medical conditions are at higher risk of severe illness from COVID-19.

How to prevent the spread of COVID-19

People who are unvaccinated, have weakened immunity or underlying medical conditions (cancer, hypertension, diabetes), or on long-term steroid therapy are at higher risk of getting COVID-19. The following are the preventive measures:

  • Vaccination: Get fully vaccinated with an authorized COVID-19 vaccine as soon as possible. Get a booster shot when available and recommended.
  • Mask up: Wear a mask covering your face and nose (preferably an N-95 type) when in crowded places or close to infected people. Vaccinated individuals are encouraged to wear masks to prevent the spread of the Delta variant of the COVID-19 virus.
  • Maintain a distance of 6 feet: Since even people without symptoms are able to spread the virus, maintain social distancing.
  • Avoid crowded areas: Avoid restaurants, bars, fitness centers, movie theaters, and other crowded areas. Make sure indoor spaces are well-ventilated, as poorly ventilated rooms multiply the risk of infection.
  • Wash your hands frequently: Regularly wash your hands with soap and water for at least 20 seconds or use a hand sanitizer that contains at least 60% alcohol. Wash your hands:
    • Before eating or preparing food
    • Before and after touching your face or mouth
    • After visiting public places
    • After blowing your nose, coughing, or sneezing
    • After coming in close contact with or touching infected people
    • After touching animals or pets
  • Cover your mouth: If you are wearing a mask you can sneeze or cough in it. However, if you are not, cough into your elbow or use tissue paper to cover your nose and mouth. Wash your hands or use a hand sanitizer immediately if your hands were used to cover your mouth and nose.
  • Clean surfaces: Clean high-traffic areas and frequently touched surfaces inside the house daily, including door knobs, handles, tabletops, phones, keyboards, toilets, and sinks.

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Medically Reviewed on 12/2/2021
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