University Health epidemiologist answers common questions about COVID-19 delta variant, vaccines and masks

What’s different about the delta variant?

SAN ANTONIO – With kids returning to school amid another wave of COVID-19 and plenty of misinformation abound, University Health’s director of hospital epidemiology is answering some of the latest commonly asked questions.

In the video released on Friday, Dr. Jason Bowling addresses COVID-19 antibodies, breakthrough infections and why more kids are being hospitalized with COVID-19.

Some of the differences between the current delta variant of the virus and the original alpha strain include a shorter incubation time, higher viral load and often different symptoms at the onset of the infection.

“The incubation time is shorter and so instead of about 5-6 days from being exposed to getting infected, it’s more like 3-5 days. And we’re seeing patients that have delta variant have a higher viral load initially and it tends to be up in this upper respiratory tract and so we’re seeing more nasal congestion early on which is a pretty mild symptom,” Bowling said.

Unlike the original strain where the onset symptoms were more severe with fever and coughing, many people may dismiss nasal congestion as allergies or a mild cold and delay getting tested or treated, Bowling said.

Bowling said it may be hard to tell if it’s just allergies or COVID-19, but if it’s new congestion and it’s not responding to antihistamines, you should get tested.

Bowling also said the delta variant is the most virulent strain of the virus, adding that while a person with the alpha strain could infect two to three people, someone with the delta strain could potentially infect seven to eight others.

He said the reason we’re seeing more children in the hospital than we did with the alpha strain is not necessarily because it affects children more severely, but because the delta strain is more transmissible and people are taking fewer precautions than we did before. Bowling said overall, kids do seem to be getting less severe cases than adults, but because such a large number are getting infected, some are just statistically going to get sicker and need hospitalization.

Bowling countered some of the common misinformation that is leading people to resist getting the vaccine, saying:

  • People who had COVID-19 previously are not protected against the new delta variant
  • The COVID-19 vaccine went through the same process of trials and studies as previous FDA-approved vaccines
  • Full FDA approval of the COVID-19 vaccine is expected soon
  • The vaccine is probably one of the most-studied vaccines in history at this point
  • More than 300 million doses of the vaccine have been administered in the United States

Some people have asked if they should still get the vaccine if breakthrough cases still happen.

“The answer is a resounding ‘yes,’” Bowling said.

Breakthrough cases are rare and the symptoms are milder. The rates of hospitalization and death in people who are unvaccinated are much higher, he said.

Bowling said experts are still learning about how transmissible a vaccinated person is if they get a breakthrough case. They may have a high viral load similar to someone who is unvaccinated but that may last for a shorter time compared to someone who is unvaccinated because the vaccinated person’s immune response reacts to the virus and starts to fight it off right away, he said.

And for those wondering if masks are effective?

The delta variant is still transmitted the same way as the alpha strain -- through large droplets so “Masks are still very, very effective,” Bowling said.

Watch the full video in the main video player at the top of the article to hear Bowling’s answers to the following questions:

  • If I had COVID-19 already, shouldn’t my antibodies still protect me?
  • How do I know the vaccine is safe if it got approved so fast?
  • What do you say to people who say they don’t have time to feel sick after getting vaccinated and will take their chances on catching COVID-19?
  • How common is it to feel sick after getting other vaccines, like the measles, mumps, flu, TDap, etc?
  • Are vaccinated people who get COVID-19 just as contagious as unvaccinated people?
  • Why should I get the vaccine, if breakthrough cases still happen?
  • What are your thoughts about the concern raised about antibody-mediated viral enhancement and that COVID vaccines might make people sicker than they would be with no vaccine?
  • How does the delta variant affect vaccinated vs. unvaccinated people?
  • The average age of hospitalized COVID-19 patients is dropping. Does that mean delta is more serious for younger people?
  • We’re seeing more children hospitalized with COVID-19 now. Is delta more dangerous for them?
  • How are the symptoms of the delta variant different from the original virus?
  • How can I tell if it’s COVID-19 and not seasonal allergies?
  • Do masks still protect us from the delta variant?

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About the Author:

Julie Moreno has worked in local television news for more than 20 years. She came to KSAT as a news producer in 2000. After producing thousands of newscasts, she transitioned to the digital team in 2015. She writes on a wide variety of topics from breaking news to trending stories and manages KSAT’s daily digital content strategy.