What You Need to Know About the COVID-19 Delta Variant

What is a variant?

When a virus spreads and infects large numbers of people, it is constantly replicating, and in that process it has the opportunity to mutate into slightly different forms. These mutations may not be much different from the original virus, but in some cases the virus may mutate into forms that are easier to transmit or potentially more severe. 

Why are public health officials concerned about the Delta variant?

The Centers for Disease Control and Prevention (CDC) has labeled the Delta variant a “variant of concern” because as of July 2021, it appears to be the most contagious strain of COVID-19 so far. In an internal document obtained by the New York Times, the CDC called the Delta variant “more transmissible than the viruses that cause MERS, SARS, Ebola, the common cold, the seasonal flu and smallpox, and it is as contagious as chickenpox.” The original COVID-19 virus strain had already been considered more contagious than the flu.

How protected are fully vaccinated older adults from Delta?

In its latest guidance, the CDC noted that COVID-19 infections may “happen only in a small proportion of people who are fully vaccinated, even with the Delta variant. When these infections occur among vaccinated people, they tend to be mild.” On July 30, NBC News reported that “breakthrough cases” — cases in people who are fully vaccinated — represented less than .08% of current COVID-19 cases.

Ongoing vaccine trials have demonstrated that the existing COVID-19 vaccines may protect against the Delta variant. CDC director Rochelle Walensky has said that the three COVID-19 vaccines authorized in the U.S. “offer strong protection against severe disease and death.”

According to the Mayo Clinic, early research found the Pfizer-Biotech vaccine to be 88% effective at preventing symptomatic COVID-19 and 96% effective at preventing severe disease. A study of the effectiveness of just one dose of the Moderna vaccine found that it was 72% effective at preventing symptomatic COVID-19 and 96% effective at preventing severe disease.

What should fully vaccinated older adults do during this increase in positive cases?

For your protection and the protection of your community, the CDC is now recommending that fully vaccinated Americans resume wearing masks in indoor public spaces if:

  • You are “in an area of high or substantial transmission.”
  • You have a weakened immune system or are at high risk for severe disease.
  • You live with someone who is unvaccinated, has a weakened immune system, or is at high risk for severe disease.

And as always, your personal doctor is your best resource for advice on your specific circumstances as the situation continues to evolve.

The above is shared for informational purposes only. We are not infectious disease experts and you should consult with trusted, independent, reputable sources before acting on any content on this website, especially if you have a medical condition or are at increased risk for contracting COVID-19. The content is not intended to be a substitute for professional medical or health advice. Never disregard professional medical or health advice or delay in seeking it because of something you have read on our site.

Visits may be subject to health screening, face coverings, social distancing, proof of COVID-19 vaccination and/or proof of negative COVID-19 test. Requirements vary by community in accordance with state or local directives or recommendations by the CDC. Please contact us for details.

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