mRNA Jabs Reduced Healthcare Personnel Covid Risk by 89-96%

mRNA Jabs Reduced Healthcare Personnel Covid Risk by 89-96%

COVID-19 vaccines are highly effective in preventing symptomatic illness among health care workers in real-world settings.

The study, published in the New England Journal of Medicine, found that health care personnel who received a two-dose regimen of Pfizer–BioNTech vaccine had an 89% lower risk for symptomatic illness than those who were unvaccinated. For those who received the two-dose regimen of the Moderna vaccine, the risk was reduced by 96%.

The researchers also found that the vaccines appeared to work just as well for people who are over age 50, are in racial or ethnic groups that have been disproportionately affected by COVID-19, have underlying medical conditions and have greater exposure to patients with COVID-19.

The vaccines’ effectiveness was, however, lower in immunocompromised people.

“That this study demonstrated the effectiveness of the Pfizer–BioNTech and Moderna COVID-19 vaccines to protect health care workers — people who worked tirelessly and at great potential risk to care for their friends and neighbors — is a major statement to address any remaining skepticism about the importance of everyone getting vaccinated,” said Dr. David Talan, a professor of emergency medicine and of medicine and infectious diseases at the David Geffen School of Medicine at UCLA, and the study’s co-lead author.

The project, Preventing Emerging Infections through Vaccine Effectiveness Testing, or PREVENT, was conducted with researchers from the University of Iowa’s Carver College of Medicine. The study evaluated nearly 5,000 health care workers — 1,482 who had tested positive for COVID-19 and displayed symptoms of the disease and 3,449 who had COVID-19–like symptoms but had tested negative for the disease. The participants were from 33 U.S. academic medical centers, including Olive View–UCLA Medical Center in Sylmar, California.

All of the participants completed surveys covering their demographic information, job type and risk factors for severe disease from COVID-19, as well as their vaccination status.

Other findings include:

  • A two-dose regimen of either of the mRNA vaccines reduced the risk of illness by 95% among Black and African American people, 89% among Hispanic people, 89% among Asian or Pacific Islander people, and 94% among American Indians and Alaskan Native people, compared to unvaccinated people.
  • Of all those who received a single dose of either of the two-dose mRNA vaccines, the risk of illness was reduced by 86% among Black and African American people, 82% among Hispanic people, 80% among Asian or Pacific Islander people, and 76% among American Indians and Alaskan Native people compared to unvaccinated people.
  • For people who are obese or overweight, a two-dose regimen reduced the risk of illness by 91%; among the same group, partial vaccination reduced the risk by 76% among partially vaccinated compared to unvaccinated.
  • For people who have hypertension, a two-dose regimen of either mRNA vaccine reduced the risk of illness by 92%, and partial vaccination reduced the risk by 83% among partially vaccinated compared to unvaccinated.
  • For people who have asthma, a two-dose regimen of either mRNA vaccine reduced the risk of illness by 91%, and partial vaccination reduced the risk by 78% among partially vaccinated compared to unvaccinated.
  • For immunocompromised people, the risk of illness was reduced by 39% whether they received a single dose or two doses of either mRNA vaccine.
  • Sixty-two people in the study were pregnant at the time they were surveyed. Vaccination was 77% effective in preventing symptomatic COVID-19 illness among pregnant people who had received at least one dose of one of the mRNA vaccines.

Because of the relatively short time period of the study — from December 2020 to May 2021 — the research does not address how long vaccines continue to provide protection against COVID-19. In addition, data was collected before the emergence of the delta variant, so the vaccines’ effectiveness today may be different than they would be against earlier variants.

PREVENT is a collaboration between EMERGEncy ID NET — a CDC-supported network led by Talan that comprises 12 U.S. emergency departments and focuses on studying emerging infectious diseases — and a previously assembled group of sites that worked under Project COVERED, another CDC-funded effort to assess the risk to emergency department providers of acquiring COVID-19 through direct contact with patients and to determine ways to mitigate that risk.

New Study: Covid-19 Shaved Up to 8 Years From Average Lifespan

New Study: Covid-19 Shaved Up to 8 Years From Average Lifespan

At its peak, COVID-19 drastically reduced the average human lifespan — by as much as nine years in one U.S. state — according to a new longevity metric developed at UCLA. 

Sociology professor Patrick Heuveline devised the metric, called the mean unfulfilled lifespan, to assess the impact of temporary “shocks” like the novel coronavirus on average length of life. To date, the pandemic has claimed the lives of more than 4.2 million people worldwide.    

The tool allows demographers to conduct fine-grained analyses in specific regions over various periods of time, offering a new and more dynamic way of gauging how different areas of the country and the world experience decreases in lifespans over the course of the pandemic, Heuveline said.

Heuveline’s analysis, published online in the open-access journal PLOS One, suggests, for example, that as COVID-19 peaked in New Jersey in mid-April 2020, the average lifespan in the state plummeted by almost nine years, the most dramatic example from the U.S.

UCLA sociologist Patrick Heuveline
UCLA sociologist Patrick Heuveline

Demographers typically calculate lifespan using a metric known as period life expectancy at birth, or PLEB, which is the average number of years a person born at a certain time would be expected to live if future death rates remained at present levels. When researchers factor in the impacts of a given cause of death — a steady increase in heart attacks or car accidents, for instance — they see how these factors can reduce PLEB.

However, calculating changes to life expectancy in this way cannot adequately capture the effect of large, temporary shocks like natural disasters or the COVID-19 pandemic, in which mortality conditions are rapidly shifting, Heuveline said.

To more clearly illustrate the impact of such phenomena, Heuveline’s mean unfulfilled lifespan measures the difference between the average age at death of individuals who died within a given time frame and the average age these people would have been expected to reach had there not been a temporary shock.

“As did a few other demographers, I initially tried to convey the mortality impact of COVID-19 by assessing how much life expectancies would decline during the pandemic,” he said. “When mortality conditions are continuously changing, however, life expectancies are hard to interpret, and I wanted to provide a more intuitive indicator of that mortality impact.” 

► Read about Patrick Heuveline’s previous research on COVID-19 and life expectancy.

Heuveline demonstrated the mean unfulfilled lifespan by applying it to COVID-19 mortality data from regions with similarly sized populations, including New Jersey, Mexico City, Lombardy in Italy, and Lima, Peru. He compared decreases in life expectancy by calendar quarter (from March 31, 2020 to March 31, 2021) and using rolling seven-day windows (from March 15 to June 15, 2020). The latter analysis suggested that the mean unfulfilled lifespan peaked at 8.91 years in New Jersey, 6.24 years in in Mexico City, 6.43 years in Lombardy and 2.67 in Lima. 

In addition, his study found that during the month of April 2020, the mean unfulfilled lifespan may have reached 12.7 years in the Guayas province of Ecuador.

Heuveline noted that uncertainties in calculating mean unfulfilled lifespan may arise from potential differences between deaths related to temporary shocks like the pandemic and actual or excess deaths — differences that, when accounted for, may push the peak unfulfilled lifespan figures seen in the study even higher. His analysis demonstrates how these issues can be factored into calculations.

Heuveline said he hopes the new metric will eventually be applied broadly as researchers seek to better understand the impact of epidemics, natural disasters and even violence on life expectancy.

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