- New research finds that mRNA COVID-19 vaccines provide immunity for at least 6 months.
- But since COVID-19 is so new, experts are not sure whether immunity will decrease thereafter.
- Experts believe more research will be needed to understand whether people need regular boost shots for COVID-19.
The COVID-19 vaccines manufactured by Pfizer and Moderna are very effective in preventing COVID-19 cases in real conditions, and research suggests that they should maintain their effectiveness over time.
What remains unclear, however, is exactly how long the COVID-19 vaccines will last, if shots may be needed along the way, or if vaccines need to be adapted to combat emerging variants of the virus.
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They found that the messenger RNA (mRNA) vaccines developed by pharmaceutical companies Pfizer-BioNTech and Moderna accounted for 80 percent of cases after the first dose and 90 percent after the second dose.
The frontline workers in the study were tested for COVID-19 every week for 13 weeks.
According to researchers, the lack of positive COVID-19 tests in the study group indicates that the vaccines reduce the risk of SARS-CoV-2 being transmitted to others through vaccinations.
Reducing the risk of communicable infection, which can occur in people with asymptomatic infection or among people a few days before the onset of symptoms, is especially important among healthcare professionals, first responders and other essential and front-line workers, as they has the potential to transmit the virus through regular close contact with patients and the public, ”reads the report.
“There is more and more evidence showing that … the transmission of the virus after vaccination is probably very low,” said Dr. Susan Bailey, an allergist and immunologist and president of the American Medical Association, told Healthline.
Separately, Pfizer-BioNTech stated that the ongoing clinical phase 3 trial of its mRNA vaccine shows that strong vaccination continues for at least 6 months among vaccinated individuals.
Researchers found that the vaccine was 100 percent effective against serious diseases as defined by the CDC, and 95.3 percent effective against severe COVID-19 as defined by the Food and Drug Administration (FDA).
It has also been found that the vaccine is 100 percent effective against one of the most important COVID-19 variants (known as B.1.351) that is currently widely distributed in South Africa.
A study involving 12,000 vaccinated individuals also found ‘no serious safety issues’ with the Pfizer-BioNTech vaccine, the companies announced.
“The good news is that the immunity in Pfizer’s 6-month status report remains very strong, and we expect it to remain strong,” Bailey said.
“These people [in the study] the vaccine had the longest, and it tells us that it lasts at least 6 months, ”Bailey added. ‘But it’s definitely longer than that – it’s not just going to decrease after 6 months. I would have been worried if the efficiency had dropped by a third or a half. ‘
The fact that the effectiveness of the COVID-19 vaccine remained virtually unchanged during the study period is an indication that the protection will be lasting.
Bailey noted that some vaccines, such as measles, mumps and rubella, usually confer lifelong immunity. Others, like the flu vaccine, need a new shot every year.
“We do not know in which camp the COVID-19 vaccine will fall,” she said. “If we do need a boost shot for COVID-19, we know it will be easy to manufacture” thanks to the new mRNA technology, she added.
Bailey said the vaccines currently in use appear to be effective against the COVID-19 variants distributed in the United States. But as the coronavirus continues to mutate, more resistant variants may emerge.
“My prediction is that a situation in which we will have to take a booster shot in the future is not because the first dose of vaccine has faded, but because there may be a new variant,” she said.
As noted in the research, vaccines do not eliminate the risk of developing COVID-19.
In a recent report on 100 COVID-19 cases that occurred at vaccinations in the state of Washington, the public raised alarm.
But experts said such “breakthrough” cases are expected and are only a fraction of the more than 1 million Washington residents who have been vaccinated.
“To find evidence of vaccine breakthroughs, we remind you that even if you are vaccinated, you should still wear a mask, do social distance and wash your hands to prevent COVID-19 from spreading to others. which has not yet been vaccinated, “he said. Dr. Umair A. Shah, Secretary of Health for Washington State.