Recent research published in the New England Journal of Medicine, and conducted in Scotland examined the protective effect of vaccination against COVID-19 found that vaccination was 90% effective in preventing death. This study is the first of its kind to be conducted across the entire country to examine how effective the vaccines are in preventing death from COVID-19. The majority of cases studied were infected with the Delta variant. Researchers reported that vaccination with the Oxford-AstraZeneca vaccine and the Pfizer-BioNTech vaccine was 91%, and 90% effective in preventing deaths, respectively, among people who have received two doses of each vaccine. 

Additional research suggests that vaccination is responsible for saving 140,000 lives in the United States through May 2021. During that time, there were 570,000 deaths of COVID-19 and the researchers estimated that the number would have reached 709,000 deaths if not for vaccination. The same study suggested that New York state had the greatest reduction in COVID-19 deaths, with 12 fewer deaths for every 1000 cases compared to the projected numbers without vaccination. 

French researchers also reached similar conclusions when examining 11.3 million people who were over 50 years old and vaccinated, and compared them to a group of the same number and age, that was unvaccinated, between December 2020 and July 2021. Researchers found a 90% decrease in the risk of hospitalization and death after 14 days of the second dose of vaccination. These results included cases of the Delta variant, which had emerged in France one month before the end of the study. 

According to the United States Centers for Disease Control and Prevention (U.S. CDC), reports of death after COVID-19 vaccination are still rare. Between December 2020, and November 2021, the total number of COVID-19 vaccine doses administered in the United States is 459 million doses. In this duration, Vaccine Adverse Event Reporting System (VAERS) has reports of death after the vaccine for 0.0022% of vaccinated cases. Health providers are required to report any death after COVID-19 vaccination, even if it is unclear if this death is caused by the vaccine. This is why reports of death through VAERS do not mean the vaccine caused the health problem that ended in death. 

Other research has suggested a relationship between the vaccination by the J&J/Janssen COVID-19 Vaccine, and six confirmed cases of death as a result of blood clots. Researchers found the following:

People who received the Pfizer COVID-19 vaccine had nearly four deaths reported for every 1,000 vaccinated people after the first dose, and slightly less deaths after the second dose. In the unvaccinated comparison group, there were nearly 11 deaths for every 1,000 people during the same year.

People who received the Moderna COVID-19 vaccine also had nearly three deaths for every 1,000 people after the first dose, and nearly three deaths after the second dose. In the unvaccinated comparison group, there were nearly 11 deaths for every 1,000 people during the same year.

For Johnson & Johnson COVID-19 vaccine recipients, there were nearly eight deaths for every 1,000 people vaccinated with this vaccine. In the unvaccinated comparison group there were nearly 14 deaths for every 1,000 unvaccinated people during the same year.

The majority of research supports the safety of the vaccines and their benefit in reducing deaths from COVID-19 infection.

Information has circulated online claiming that the risks of COVID-19 vaccines outweigh their benefits, and that vaccines are not effective at reducing mortality. These claims are not based in fact and are typically built off of a small select amount of data, versus the large amount of data from clinical trials and other ongoing studies to research vaccines and their outcomes. 

One of the recent studies being circulated is a preprint study (meaning not yet peer reviewed) on the safety and efficacy of the Pfizer-BioNTech vaccine over 6 months, titled “Six Month Safety and Efficacy of the BNT162b2 mRNA COVID-19 Vaccine.” The authors conclude that the vaccine continues to be safe and well tolerated with a 91% efficacy: there were 77 COVID-19 cases in the vaccine group, and 850 cases of COVID-19 in the placebo group. 

The study’s findings show that 15 individuals in the vaccine group died during the study, and 14 individuals in the placebo group died during the study. After the point that patients were “unblinded” and allowed to choose whether to receive the vaccine or not, 3 individuals in the original vaccine group and 2 original placebo recipients who opted to receive the vaccine after unblinding died. This is the data that is being used by many to show that vaccines do not decrease mortality. However, there are a number of issues with using this data to  

First, none of the deaths in the vaccine group were considered related to BNT162b2 by investigators, whereas at least two of the deaths were specifically categorized as COVID-19 deaths in the placebo group. Second, these categorizations of death are not perfect. For instance, one of the categories is just “death,” and it’s not indicated if certain conditions placebo group individuals died from on the group are a result of COVID-19 or not, such as acute respiratory failure or cardiac arrest. 

Additionally, the study is not well set up to study all cause mortality as an endpoint. In order to best study that outcome, the study subjects would be individuals most at risk of dying from COVID-19: namely, older individuals and those with pre-existing conditions. The median age for this study was 51 and only participants who were healthy or had stable chronic medical conditions were eligible.

There are also more metrics for studying mortality than mortality rate. For instance, another helpful metric is the Case Fatality Rate (or CFR) which measures how many people died out of how many people had the disease. Another way to study mortality in this study specifically would be to measure how many people died of the disease outcome in each group. This would be a helpful approach given that there are many reasons that a person can die out of such a large group of people. Finally, it’s helpful to think of mortality prevention on a population level. If 91% of infections are prevented in this population, then transmission is significantly reduced for those individuals’ communities, which, in turn, reduces mortality overall.

The clinical trials of major COVID-19 vaccines show that people who are vaccinated against COVID-19 have highly reduced risks of falling severely ill from COVID-19, and highly reduced chances of hospitalization and death due to COVID-19.