Research shows that the effectiveness of the COVID vaccine has plummeted

According to reports, as the Delta variant becomes the main strain of the US coronavirus, all three COVID-19 vaccines available to Americans have lost some protection, and the effectiveness of vaccines for a large number of veterans has dropped by 35% to 85%. To a new study.

Researchers checked the records of nearly 800,000 American veterans and found that in early March, when the Delta variant gained a foothold in the American community, the three vaccines were roughly equivalent in their ability to prevent infection.

But in the next six months, the situation changed dramatically.

By the end of September, Moderna’s two doses of COVID-19 vaccine had an effective rate of 89% in March, but only 58%.

Pfizer and BioNTech also used two-dose injections whose effectiveness dropped from 87% to 45% during the same period.

The most striking thing is that the protective ability of Johnson & Johnson’s single-dose vaccine dropped from 86% to only 13% in these six months.

Survey results Published in the journal Science on Thursday.

These three vaccines performed better in terms of their ability to prevent deaths from COVID-19, but by July – as the Delta variants began to drive a three-month surge in infections and deaths – the effectiveness of the vaccines at this score also showed great difference.

Among veterans 65 years of age and older who were vaccinated with Moderna, veterans who had a so-called breakthrough infection were 76% less likely to die of COVID-19 than veterans of the same age who were not vaccinated.

Elderly veterans who received the Pfizer-BioNTech vaccine and subsequently experienced breakthrough infections had a 70% lower chance of death than their unvaccinated peers.

When an elderly veterinarian who received a Johnson & Johnson vaccination suffers a breakthrough infection, they are 52% less likely to die than their peers who have not received any vaccines.

For veterans under 65, Pfizer-BioNTech and Moderna vaccines provide the best protection against fatal COVID-19 cases, 84% and 82%, respectively. When young veterans vaccinated by Johnson & Johnson suffer a breakthrough infection, they are 73% less likely to die from COVID-19 than their unvaccinated peers.

A representative of Johnson & Johnson did not immediately respond to a request to discuss the results of the study.

The Centers for Disease Control and Prevention recommends intensified injections Everyone vaccinated against Johnson & Johnson At least two months in advance.

Also recommend booster Six months after vaccinating the second dose of Moderna or Pfizer vaccine for everyone 65 years and older; those whose physical conditions make them more susceptible to severe COVID-19 cases; those who live in nursing homes or other group settings; and People who live or work in high-risk environments such as hospitals or prisons.

In addition, it is recommended that all people with compromised immune systems receive booster shots at least 28 days after the vaccine is fully effective.

With millions of vaccinated Americans considering whether they need booster vaccines, this new study provides the most comprehensive comparison to date of the three vaccines’ performance across the country this year.

From February 1 to October 1, it tracked 780,225 veterans of the U.S. Armed Forces. Nearly 500,000 of them were vaccinated, but less than 300,000 were not vaccinated.

All people from all over the country are under the care of the Department of Veterans Affairs’ unified system, which provides health care to 2.7% of the American population. Although the groups studied differ in race and ethnicity, the record keeping that researchers rely on is uniform.

Because these people are veterans, there are six times as many men in the study population as women. And their age is too old: about 48% of people are 65 years or older, 29% are between 50 and 64 years old, and 24% are younger than 50 years old.

Although older veterans were more likely to die than younger veterans throughout the study period, the protection of vaccines against disease and death declined in both young and old.

The research was conducted by a team from the Oakland Institute of Public Health, the San Francisco Veterans Affairs Medical Center, and the University of Texas Health Sciences Center.

Dr. Barbara CohenThe lead author of the study said that in addition to the comparison of COVID-19 vaccines, the team’s analysis also provides “a lens that can make informed decisions around primary vaccination, booster injections, and other layers of protection.” This includes Mask regulations, coronavirus testing and other public health measures designed to combat the spread of the virus.

The authors say that strong evidence of reduced vaccine effectiveness should prompt even states and regions with high vaccination rates to consider retaining mask regulations. And these findings strongly support the CDC’s recent recommendation that all recipients of Johnson’s vaccine should receive boosters.

The study concluded that the Delta variant, which caused a wave of infections and deaths across the country in spring and summer, may be the factor that weakens the vaccine’s protective effect the most.

Other researchers found Similar evidence The effectiveness of the vaccine has decreased. But they believe that the immune system’s defense against SARS-CoV-2 will gradually weaken over time, regardless of whether new, More communicative strain.

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