Two Doses Of Pfizer's COVID Vaccine Are Effective Against Delta Variant

By Bill Galluccio

June 15, 2021

PANAMA-HEALTH-VIRUS-VACCINE
Photo: Getty Images

Health officials in England said that Pfizer's coronavirus vaccine is effective at protecting against the Delta variant after the second dose. The Delta variant has become the predominant strain in England and could become the dominant variant in the United States by the fall.

The variant, which was identified in India, is 40-60 percent more transmissible than the Alpha variant. Preliminary data also shows that the strain is more likely to cause serious illness, and patients sickened by the variant were twice as likely to end up in the hospital.

According to an analysis of 14,019 cases caused by the Delta variant released by Public Health England, two doses of Pfizer's vaccine were 96% effective against hospitalization from the Delta variant. They also tested AstraZeneca's vaccine, which has not been authorized in the United States, and found that two doses were 92% effective at preventing hospitalizations.

A previous analysis found that just a single dose of the vaccine was less effective against symptomatic illness caused by the Delta variant.

"It is absolutely vital to get both doses as soon as they are offered to you, to gain maximum protection against all existing and emerging variants," Dr. Mary Ramsay, head of immunization at PHE, said in a statement.

Advertise With Us
Music, radio and podcasts, all free. Listen online or download the iHeart App.

Connect

© 2025 iHeartMedia, Inc.