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COVID-19 vaccine and infections lead to partial herd immunity
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Utah may be at 20% herd immunity, infectious disease expert says

FILE: Taelor Leonelli, RN, administering the COVID-19 vaccine inside the Tooele County Health Department building. Photo: Paul Nelson, KSL NewsRadio

MURRAY, Utah — An infectious disease specialist at Intermountain Healthcare says with the number of people who have received at least one dose of the COVID-19 vaccine and the number of people with antibodies, the community may be at about 20% herd immunity. 

“We’re probably somewhere just under 20%, at this point, and that’s a rough estimate. And it’s not enough, but it is helping,” Dr. Brandon Webb said Tuesday. “Coupling that with social distancing and the masking, it’s driving our case counts down.”  

The current case counts of COVID-19 in Utah are the lowest they’ve been since October. 

Working toward herd immunity

Herd immunity means most of a population or community becomes immune to a virus, according to doctors at Johns Hopkins University.

In other words, once herd immunity reaches 80%, four out of every five people exposed to a virus would not get it, either because they have received the vaccine or have natural antibodies from viral exposure. It explains why once common illnesses like chicken pox, mumps and measles are now rare in the United States. 

Webb says nearly 20% herd immunity to COVID-19 does not eliminate the need for face coverings and social distancing. 

“The vaccine and our infection control efforts work hand-in-hand,” Webb said. 

Those same factors may be at the heart of a much-less-severe than normal flu season in Utah.

Read more: 

How To Prevent the Spread of COVID-19 Coronavirus

COVID-19 coronavirus spreads person to person, similar to the common cold and the flu. So, to prevent it from spreading:

  • Wash hands frequently and thoroughly, with soap and water, for at least 20 seconds.
  • Don’t touch your face.
  • Wear a mask to protect yourself and others per CDC recommendations.
  • Keep children and those with compromised immune systems away from someone who is coughing or sneezing (in this instance, at least six feet).
  • If there is an outbreak near you, practice social distancing (stay at home, instead of going to the movies, sports events, or other activities).
  • Obtain a flu shot.

Local resources

KSL Coronavirus Q&A 

Utah’s Coronavirus Information 

Utah State Board of Education

Utah Hospital Association

The Church of Jesus Christ of Latter-day Saints

Utah Coronavirus Information Line – 1-800-456-7707

National Resources

Centers for Disease Control and Prevention

Commonly asked questions, World Health Organization

Cases in the United States

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