Does the Pfizer vaccine protect against the delta variant of COVID?

Pfizer COVID vaccine protect against delta
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  • This story is regularly updated for relevance. Last updated: Aug. 6, 2021

The delta variant of COVID is spreading rapidly across a number of countries, including the U.K., where it has become the dominant strain. The highly transmissible variant is on the rise in the U.S. as well, currently accounting for as much as 83% of new cases. It’s now become the dominant strain in the U.S., and it’s prompting questions about whether the Pfizer vaccine protects against the delta variant.

A study from Public Health England found that a single dose of the Pfizer vaccine boosts protection against the delta variant by around 33%. Protection against the delta variant increases to 88% within several weeks of a second dose. 

Experts are emphasizing the necessity of the second dose to boost protection against COVID-19 and its variants. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, noted that the two-shot mRNA vaccines from Pfizer and Moderna are performing “very well” against the delta variant.

In early July, an Israeli study showed that the Pfizer effectiveness against the delta variant had dropped to 64%.

People who have yet to be vaccinated are more at risk. Fauci emphasized the need for a full vaccination, noting that widespread vaccines are the only route to preventing delta from becoming the dominant strain.

The delta variant, aka “COVID-19 on steroids,” has several symptoms previously unassociated with the coronavirus—from the mild (headache, runny nose) to the severe (fever, hearing loss, and even gangrene). It is spreading more rapidly than the original strain of COVID-19 and is often resulting in more instances of hospitalization and death.

As noted by Mary Ramsay, the head of immunization at Public Health England, “We expect the vaccines to be even more effective at preventing hospitalization and death, so it is vital to get both doses to gain maximum protection against all existing and emerging variants.”

Read more on the coronavirus variants:

Sources: NPR, Guardian, Washington Post, Healthline

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