mRNA Vaccines Highly Effective at Preventing Death From COVID-19 – But Less Effective at Preventing Infection

A target trial emulation study found that in an elderly population of U.S. veterans with high comorbidity burden, mRNA vaccine efficacy at preventing infection with COVID-19 was substantially lower than previously reported but effectiveness against death was very high. These finding suggest that complementary infection mitigation efforts remain important for pandemic control, even with vaccination. The study is published in the journal Annals of Internal Medicine.

The real-world effectiveness of the Moderna or Pfizer-BioNTech COVID-19 mRNA vaccines in ethnically and racially diverse populations across the entire United States is not well characterized, especially in more vulnerable populations, such as elderly persons with high comorbidity burden. The U.S. Department of Veterans Affairs (VA) health care system is the largest national, comprehensive health care system in the United States. As such, it offers the opportunity to evaluate vaccines in this population.

Researchers from Veterans Affairs Puget Sound Health Care System and University of Washington School of Medicine designed an observational study to emulate a target trial of COVID-19 vaccination versus placebo. Of the more than 5 million people receiving care in the Veterans Affairs health care system, those who received at least 1 dose of the Moderna or Pfizer–BioNTech COVID-19 vaccine from December 11, 2020, to March 25, 2021, (n = 2,099,871) were matched to unvaccinated controls in a 1:1 ratio according to demographic, clinical, and geographic characteristics. The researchers found that vaccine effectiveness at 7 or more days after the second vaccine dose was 69% for SARS-CoV-2 infection and 86% for SARS-CoV-2–related death during follow-up extending to June 30, 2021. Vaccine effectiveness did not decline when follow-up was extended from March 31 to June 30, 2021. Vaccine effectiveness against SARS-CoV-2 infection decreased with increasing age and comorbidity burden. According to the researchers, these findings suggest that protection against infection from COVID-19, even among vaccinated individuals, will require continued attention to additional mitigation strategies.

Reference: “COVID-19 Vaccination Effectiveness Against Infection or Death in a National U.S. Health Care System – A Target Trial Emulation Study” by George N. Ioannou, BMBCh, MS, Emily R. Locke, MPH, Ann M. O’Hare, MD, Amy S.B. Bohnert, PhD, Edward J. Boyko, MD, MPH, Denise M. Hynes, MPH, PhD, RN and Kristin Berry, PhD, 21 December 2021, Annals of Internal Medicine.
DOI: 10.7326/M21-3256

American College of PhysiciansCOVID-19MRNAPopularVaccine
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  • Cindy

    Claire, u are delusional. Iveectin does nothing for covid. Stop spreading inaccurate information

  • Howard Jeffrey Bender, Ph.D.

    Well, it is too bad the infection rate has been found to be less than reported, but the real problem is in the virus itself, not in its protein spikes.

    All the coronaviruses and all their variants have different protein spikes, with Delta and Omicron having spikes that are more efficient at getting around the vaccines. But the real problem is in the virus itself, not its protein shell, and why the most dangerous (MERS, SARS, and Covid-19) are so infectious. My independent research has found multiple one-in-a-million nucleotide sequence matches between all the coronaviruses and the human genome. Those sequences are the same as some of the loops of human tRNA. Using those loops and their amino acid code matches, viruses may be able to fool the nucleus membrane in cells to allow the virus to enter and associate with the human DNA, creating more opportunities for further infection. Our immune system may be compromised and may no longer be able to stop the virus and other diseases from attacking organs throughout the body. Vaccines that attack the virus protein shells while ignoring their contents are doomed to failure from the Darwin effect, but recognizing these loops suggests a possible approach to successful coronavirus vaccines. Only the infection process is considered in my work, not the innate virulence of the virus. For more info, check out this YouTube, Coronavirus – Using Your DNA Against You. https://www.youtube.com/watch?v=8dOIzD6ch8s