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Study of Veterans Finds Vaccine Protection Wanes Over Time

A new pre-print study of over 600,000 veterans by researchers from PHI and the Veterans Affairs Medical Center finds that COVID vaccine protection declined by mid-August 2021, when the highly-contagious delta variant emerged as the dominant variant. The authors say that the results demonstrate an urgent need to reinstate multiple layers of protection against infection and bolstering ongoing vaccination efforts.

  • Washington Post
a man getting a vaccine shot

new study of breakthrough infections among military veterans found that vaccine protection against the coronavirus had declined by mid-August, when the highly-contagious delta variant emerged as the dominant iteration in the country.

Using data from the Veterans Health Administration, the largest health system in the United States, researchers compared coronavirus infections by vaccination status among 620,000 veterans — representing 2.7 percent of the U.S. population — from Feb. 1 to Aug. 13.

Although the report has yet to be peer reviewed and evaluated, it indicates that virus immunity decreased over time and that its decline was different for each of the three vaccines available in the United States.

According to the study, the greatest waning was presented by the Johnson & Johnson product, with protection falling from 88 percent in March to 3 percent in August. In the same period, it declined for the Pfizer-BioNTech vaccine from 91 percent to 50 percent. For Moderna, protection fell from 92 percent to 64 percent.

With breakthrough infection patterns remaining consistent in relation to time, age and vaccine eligibility, researchers pinpointed the delta variant as the “primary determinant of infection.”

“These results demonstrate an urgent need to reinstate multiple layers of protection against infection, such as masking and physical distancing, while also bolstering current efforts to increase vaccination,” the researchers said in the study.

See other new stories noting the study:

CNN: Covid-19 numbers are getting better. But where they go from here will depend on vaccinations, Fauci say

New York Post: Experts urge booster shot ASAP for Johnson & Johnson vaccine

CBS News: Myeloma may have made Powell more vulnerable to COVID

News Medical: Waning COVID vaccine efficacy especially against reinfection

Hankyoreh South Korea: Janssen booster shots likely to be moved up amid revelations of plummeting effectiveness 

Click below to read the full Washington Post story.

Originally published by Washington Post

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