- New research finds that COVID-19 mRNA vaccines provide immunity for at least 6 months.
- But since COVID-19 is so new, experts aren’t sure if immunity will drop afterwards.
- Experts say more research will be needed to understand whether people will need regular booster photos for COVID-19.
COVID-19 vaccines produced by Pfizer and Moderna are extremely effective in preventing COVID-19 cases in real-world conditions, and research suggests that they should be effective over time.
However, what remains unclear is exactly how long vaccines will prevent COVID-19, whether booster vaccines may be needed on the road, or whether vaccines will need to be modified to combat emerging variants of the virus.
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They found that messenger RNA (mRNA) vaccines developed by pharmaceutical companies Pfizer-BioNTech and Moderna prevented 80 percent of cases after the first dose and 90 percent after the second dose.
The front-line workers in the study were tested for COVID-19 every week for 13 weeks.
The researchers said that the lack of positive COVID-19 tests in the study group indicates that vaccines reduce the risk of transmitting SARS-CoV-2 by vaccinated people to others.
“Reducing the risk of communicable infection, which can occur in people with asymptomatic infection or in people a few days before the onset of symptoms, is particularly important among healthcare professionals, respondents and other essential workers and first responders. line, given their potential to transmit the virus in close contact with patients and the public ”, the report states.
“There is growing evidence that … the transmission of the virus after vaccination is probably very low,” Dr. Susan Bailey, an allergist and immunologist and president of the American Medical Association, told Healthline.
Separately, Pfizer-BioNTech said that the phase 3 clinical trial of the vaccine or mRNA shows that strong immunization persists for at least 6 months among vaccinated individuals.
The researchers found that the vaccine was 100% effective against severe disease, as defined by the CDC, and 95.3% effective against severe COVID-19, as defined by the Food and Drug Administration (FDA).
The vaccine has also been shown to be 100% effective against one of the major variants of COVID-19 (known as B.1.351) currently circulating widely in South Africa.
A study that included 12,000 vaccinated people also found “no serious safety concerns” with the Pfizer-BioNTech vaccine, the companies said.
“The good news is that in the 6-month report from Pfizer, immunity remains very strong and we anticipate that it will remain strong,” Bailey said.
“These people [in the study] we had the vaccine the most and he tells us that it lasts at least 6 months “, added Bailey. “But it is definitely longer than that – he will not give up only after 6 months. I would have been worried if the effectiveness had decreased by a third or a half “.
The fact that the efficacy of COVID-19 vaccine remained almost unchanged during the study period is an indication that protection will be lasting.
Bailey noted that some vaccines, such as those for measles, mumps and rubella, generally confer immunity for life. Others, such as the flu vaccine, require a new vaccine every year.
“We do not know in which camp the COVID-19 vaccine will fall,” she said. “If we need a booster shot for COVID-19, we know it will be easy to produce,” thanks to new mRNA technology, she added.
Bailey said the vaccines used now appear to be effective against COVID-19 variants circulating in the United States. But as the coronavirus continues to move, more resistant variants may appear.
“My prediction is that a situation in which we should have a booster shot in the future is not because the first dose of vaccine has faded, but because there is a new variant that could appear,” she said.
As mentioned in the research, vaccines do not completely eliminate the risk of developing COVID-19.
A recent report on 100 COVID-19 cases in vaccinated people in Washington State has raised some public alarm.
But experts say such cases of “discovery” are expected and represent only a fraction of Washington’s more than 1 million people who have been vaccinated.
“Finding evidence of vaccine detection reminds us that even if you have been vaccinated, you must still wear a mask, practice social distancing, and wash your hands to prevent the spread of COVID-19 to others who have not been vaccinated. Said Dr. Umair A. Shah, Washington’s secretary of health.