COVID-19 Delta variant is twice as contagious as other COVID-19 strains

In Arizona and other states in the U.S., COVID-19 cases are on the rise due to the Delta variant.

As the strain continues to spread, epidemiologist Dr. Eric Fiegl-Ding described just how much more contagious the new variant is.

"It is a 2.0 pandemic virus," said Dr. Feigl-Ding. "It is leaps and bounds more contagious than the original virus."

According to a leaked CDC internal report, the Delta variant is just as contagious as chickenpox, and much more severe.

"This is very different than what we had before," said Dr. Feigl-Ding. "It ha a much higher viral load. It spreads much faster, and it could spread even with five to 10 seconds of fleeting exposure."

Dr. Feigl-Ding says the strain is four times more severe for the unvaccinated, in terms of risk for hospitalization. The two-dose vaccines protect a person against the original COVID-19 strain by 90%, but that number is stands at 60% or 70% with the Delta strain.

"This is inherently why we need to mask, and this is why the CDC re-instituted its policy to mask in indoor public places,"said Dr. Feigl-Ding.

The CDC study out of Massachusetts found that a 4th of July party contributed to a surge in Delta strain cases. About 75% of the 450 people infected were fully vaccinated.


Dr. Fiegl-Ding says getting vaccinated and continuing to take precautions is so important.

"Vaccines are great. They save your life, they prevent hospitalizations, lower the risk by 90%, but it is not a bulletproof vest that you can go out and party unlimited, because you are transmitting it to others and vaccinated people do get persistent symptoms if they do get infected," said Dr. Feigl-Ding.

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COVID-19 resources

CDC Website for COVID-19 (In Spanish/En Español)

AZDHS Website for COVID-19 (In Spanish/En Español)

AZDHS Website for COVID-19 Vaccination (In Spanish/En Español)