The risk of getting Covid-19 for people who had been fully vaccinated, described as “breakthrough infections” remained very low, according to a new study from New York.
At Rockefeller University, which had 417 employees fully vaccinated with either the Pfizer or Moderna shots, the study found only two of them or 0.5%, had breakthrough infections later. The study was published Wednesday in the New England Journal of Medicine.
New Study Finds Only 2 Breakthrough Covid-19 Infections Among Hundreds Fully Vaccinated
The researchers wrote in the study that they had characterized bona fide vaccine breakthrough examples showing up as clinical symptoms. They added, the observations did not in any way undermine the importance of the urgent efforts by state and federal administrations to vaccinate the U.S. population. The observations also lent support to efforts for advancing a new vaccine booster (as also a pan-coronavirus vaccine) for providing increased protection against variants.
According to the Rockefeller University researchers, the coronavirus variants that showed several differences from the original strain caused the breakthrough infections.
One of the infected patients had the E484K mutation first identified in the B.1.351 variant found originally in South Africa. E484K had come to be known as an “escape mutant” as it showed the ability to escape some of the antibodies coronavirus vaccines produced. The mutations in the infections of both study participants included D614G, which was found early in the pandemic.
One case of breakthrough infections involved a healthy 51-year-old woman who had been administered her second Moderna vaccine dose on February 19. She tested positive for Covid-19 nineteen days later, on March 10 after symptoms appeared.
A healthy 65-year-old woman was the other breakthrough infection case. She had received her second Pfizer vaccine dose on February 9. She later came to know that her partner, who had not been vaccinated, tested Covid-19 positive on March 3. She later developed symptoms of her own and on March17 tested positive for Covid-19.
According to experts, more research would determine whether similar findings involved breakthrough infections, or the emergence of variants would be seen in a larger group of participants from different parts of the United States.
According to experts, some Covid-19 breakthrough cases could be expected to be seen in people who had been fully vaccinated, since no vaccine was 100% effective.
The US Centers for Disease Control and Prevention last week told CNN that the agency had received less than 6,000 reports so far, of breakthrough coronavirus infections while 84 million people had been fully vaccinated nationwide.
According to the CDC, breakthrough cases were seen in people across all ages that had been vaccinated, but a little over 40% were in people 60 or older. Breakthrough infection prevalence among females was higher with 29% being asymptomatic.
The agency added that it had developed a national database of Covid-19 breakthroughs for state health departments to report them.
In a statement to CNN, the CDC said vaccine breakthrough infections made up a small percentage of fully vaccinated people. The agency recommended that all eligible people get a COVID-19 vaccine as soon as they had one available.
In a separate report, CNN cited new data published Wednesday from the New England Journal of Medicine saying the mRNA Covid-19 vaccines made by Pfizer/BioNTech and Moderna appeared to pose no serious risk during pregnancy.
Covid-19 affected pregnant women were at a higher severe illness risk and might be at increased risk for adverse outcomes, such as preterm birth, according to the US Centers for Disease Control and Prevention. The study coupled with existing research showing mRNA vaccines were effective in lactating and pregnant women, suggested that the vaccine benefits outweighed the risks.
The study which involved 35, 691 pregnant participants aged 16 to 54.