Fauci says all 3 COVID-19 vaccines effective against delta variant

All three COVID-19 vaccines approved for emergency use by the FDA — Pfizer, Moderna and Johnson & Johnson — are effective against the highly infectious delta variant, the nation’s leading infectious disease expert said during a White House press briefing Thursday. 

"The world is understandably worried about the delta virus variant," Dr. Anthony Fauci, the director of the U.S. National Institute of Allergy and Infectious Diseases, said. "The vaccines indeed are effective against it."

Fauci cited various studies, including three separate real-world studies which showed Pfizer was 79%, 88% and 96% effective against the delta variant.

Fauci noted a study in Scotland, which showed two doses of the Pfizer vaccine were 79% protective against the variant. Meanwhile, a study from England showed that in symptomatic infection, two doses of the Pfizer vaccine were 88% effective. In hospitalizations in England, two doses of the vaccine were shown to be 96% effective.

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In one study, researchers in England studied how effective the two-dose AstraZeneca and Pfizer-BioNTech vaccines were against the fast-spreading delta strain compared with the alpha variant that was first detected in the U.K. The vaccines were protective for those who got both doses but were less so among those who got one dose.

"You can make a real-world assumption that our data, applicable to Pfizer, are also applicable to Moderna," Fauci said.

In one study, Moderna said that an analysis of blood samples from people who had received the company’s vaccine showed a strong level of antibodies indicative of robust protection against known variants. 

Fauci also pointed to indirect and direct evidence of the Johnson & Johnson vaccine’s effectiveness against the delta variant. Tests that analyzed the blood of people vaccinated with the single dose of the J&J vaccine showed the delta variant and other variants were effectively neutralized.

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Johnson & Johnson announced last week that preliminary data showed their one-shot COVID-19 vaccine provides "strong" protection against the delta variant, according to a company news release. The company said its vaccine provides a durable immune response for at least eight months against the delta variant. 

"Please get vaccinated. It will protect you against the surging of the delta variant," Fauci said Thursday.

The delta variant is overtaking other strains and spreading in the U.S., particularly in areas with low vaccination rates.

In the U.S., the variant makes up at least 20% of reported COVID-19 cases and has become the most dominant strain in the country, according to health officials. In Missouri, the state is seeing an alarming rise in cases because of a combination of the fast-spreading delta variant and resistance among many people to getting vaccinated.

Last week, the head of the World Health Organization said the delta variant was "quickly becoming the dominant strain in many countries," and thus, the world is in a "very dangerous period" of the COVID-19 pandemic.

"Delta is spreading in at least 98 countries and is spreading quickly in countries with low and high vaccination coverage," WHO Director-General Dr. Tedros Adhanom Ghebreyesus said.

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"I have urged leaders across the world to work together to ensure that by this time next year 70 percent of all people in every country are vaccinated," Tedros said. "This is the best way to slow the pandemic, save lives, drive a truly global economic recovery and along the way prevent further dangerous variants from getting the upper hand."

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He added that 3 billion doses of COVID-19 vaccines have already been distributed and "it’s within the collective power of a few countries to step up and ensure that vaccines are shared."

"By the end of this September, we are calling on leaders to vaccinate at least 10 percent of people in all countries. This would protect health workers and those at most risk," Tedros continued.

This story was reported from Los Angeles.