If You Got Pfizer, This Is How Much You're Protected From the Delta Variant
New data shows that the variant does reduce the vaccine's efficacy.
The Delta variant is poised to take over the U.S. as the dominant COVID strain, and as it spreads, experts are looking to learn more about how the variant works and how it could affect the course of the pandemic. Emerging research has found that not only is this new variant more transmissible than others, but it may be more deadly, too. Unfortunately, it also appears that existing vaccines may be affected by the Delta variant. New data has found that those who've been vaccinated with Pfizer do have protection against the Delta variant, but there is a clear drop in how well the vaccine works against this variant of concern.
A new study out of Israel, whose findings were released on July 5, suggests that the Pfizer vaccine is less effective at protecting against COVID caused by the Delta variant than it is against other strains, as The Wall Street Journal reports. The data was collected from June 6 through early July, while the country was experiencing a massive outbreak from the Delta variant.
According to Israel's Health Ministry, the Pfizer vaccine was 64 percent effective against COVID infection amid the country's Delta-induced outbreak. The vaccine was previously 94 percent effective against infection. But even amid the Delta outbreak, the Pfizer vaccine was still 94 percent effective at preventing severe illness, only down from 97 percent before.
This data comes at a time when the Delta variant is presumed to be causing around 90 percent of new COVID infections in Israel, per WSJ. The seven-day average of overall COVID cases in the country just rose to 300 on July 6, when there were only around 10 daily new cases in June. Israel has already reimposed its indoor mask requirement to try to combat the spread of the Delta variant and top Israeli officials are set to meet to discuss implementing more measures and restrictions.
Best Life has reached out to Pfizer about the new findings, but has not yet heard back. The pharmaceutical company declined to comment to both WSJ and Reuters, but Reuters said a Pfizer spokesperson cited other research showing that the antibodies created by its vaccine were still able to neutralize the Delta variant, though at reduced strength.
Though they didn't identify a particular study, there was research published in early June in the medical journal The Lancet that showed that Pfizer recipients had fewer antibodies against the Delta variant than other strains of the virus. The study involved 250 participants who received either one or two doses of the Pfizer vaccine. Then, the researchers used blood tests to measure their antibody levels, comparing antibody responses to five different COVID strains, including the Delta variant. According to their findings, people who were fully vaccinated with Pfizer had fives times lower levels of antibodies against the Delta variant compared to the original COVID strain that the vaccine was targeted to fight.
Reduced vaccine efficacy against the Delta variant could be a concern in the U.S., where the variant is now spreading heavily, particularly in the Midwest and South. During a White House COVID press briefing on July 1, Rochelle Walensky, MD, the director of the Centers for Disease Control and Prevention (CDC), said that about 1 in 4 new COVID cases in the U.S. were due to the Delta variant. "The Delta variant is predicted to be the second most prevalent variant in the United States, and I expect that in the coming weeks it will eclipse the Alpha variant," Walensky said at the briefing. "And in some regions of the country, nearly one in two sequences is the Delta variant."
Moderna also recently released data showing how its vaccine stacks up against the Delta variant. According to a June 29 statement from the company, there is a more than twofold reduction in antibody response against the Delta variant. But the Moderna vaccine, like the Pfizer vaccine, still provides ample protection, making them—along with the single Johnson & Johnson dose—the best option at combatting COVID, even as the Delta variant takes over.
"The science is clear. The best way to protect yourself against the virus and its variants is to be fully vaccinated," White House COVID adviser Anthony Fauci, MD, said during the July 1 press briefing. "It works. It's free. It's safe. It's easy."