How Delta variant differs from original COVID-19 strain

COVID variant
Posted at 5:00 AM, Aug 13, 2021
and last updated 2021-08-13 05:17:18-04

NORFOLK, Va. - The Delta variant of COVID-19 is now the dominant strain.

That means it's what the vast majority of people are getting infected with, and it differs in some big ways from the original strain.

"This is a very different and very dangerous virus," said Dr. Edward Oldfield III, an infectious disease specialist at Eastern Virginia Medical School.

He's breaking down what we know so far about Delta.

Highly contagious

Dr. Oldfield says one of the biggest differences is how contagious the Delta variant is.

While the original strain would infect two to three people, this variant infects an average of six to eight people for every infected person.

An infected person also has about 1,000 times more virus than they did with the original strain.

Vaccinated people can spread virus

Earlier this year, it was not likely for someone to spread the virus once they were vaccinated, but that has changed with this variant.

"That's why the CDC changed the recommendation and said even vaccinated people should now wear a mask," said Oldfield.

Are patients sicker?

Research is ongoing as to how to sick it's making people, but Oldfield says doctors at Sentara Norfolk General Hospital tell him their patients are sicker than what we saw in the spring and winter.

We're also seeing more children becoming infected.

About 15 to 17 percent of all new infections are in children, but many of them are unvaccinated since the vaccines are not approved for children under twelve.

Vaccines still work

"The important thing to remember is that the vaccines work very well against Delta. They worked, Pfizer and Moderna, 95 percent against the original strain. You're about 88 percent against Delta," said Oldfield.

Even more importantly is how well the vaccines prevent severe disease and death.

Dr. Oldfield says it's only slightly less than the original strain - 96 percent effective compared to 98 percent.

Right now, 96 percent of people in the hospital or dying from COVID-19 complications are unvaccinated.

Unless someone gets the one-dose Johnson and Johnson vaccine, Dr. Oldfield says it's crucial people get both doses.

One dose of Pfizer or Moderna is only about 34 percent effective.