PHILADELPHIA (WPVI) -- Experts and researchers here say the delta variant now accounts for nearly all new COVID-19 cases in the Delaware Valley.
What we've said all along is the more the virus spreads, the more opportunities it has to change. The vaccine helps protect against serious illness from the delta variant, but the concern is what might be around the corner.
Dr. Frederic Bushman, chairman of the microbiology department at Penn Medicine, says sequencing shows almost all cases of COVID-19 in our area are now delta variant.
It's said to be as contagious as chicken pox and can cause more severe illness than previous variants. Dr. Bushman says what's also concerning is "it seems to be able to infect people who are already vaccinated. You are still well-off, you are going to get much less sick. The vaccine is greatly helping you."
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But he says this could be a sign the virus is changing more aggressively and future variants could start to elude the vaccine.
As of now, breakthrough cases are rare and deadly ones are even more so. Some 99.9% of people fully vaccinated won't suffer serious consequences.
For those who still become infected, most won't have serious symptoms, as seen with the recent outbreak in Provincetown, Massachusetts.
"346 people who were vaccinated became infected but only five of them were hospitalized and no one died," said Dr. Bushman.
The best way to protect yourself and others is to take appropriate precautions.
"In crowded places, indoor environments where there's a lot of travelers, wearing masks is a good idea even if you are vaccinated," Bushman said, adding "I'm afraid we are going to have to adjust to the idea we're going to be seeing new plans, new guidance going forward just in response to the epidemic."
He doesn't think the virus will change enough to completely evade the vaccine, but the sooner we can stop the spread of the virus, the better and that includes both here in the U.S. and globally.