Pfizer, Moderna vaccines 90% effective outside lab conditions, CDC finds
The Centers for Disease Control and Prevention released an interim report last week pertaining to the efficacy of vaccines distributed to healthcare personnel and frontline workers since the initial rollout in December.
The report revealed the efficacy rate of the first dose of both the Pfizer and Moderna mRNA vaccines was 80 percent effective against coronavirus infections two weeks after being administered.
The second dose of the vaccines had a 90 percent efficacy rate, confirming the mRNA vaccines are effective against coronavirus infections in real-world conditions.
The study was conducted by having healthcare workers, first responders and other essential workers who took the vaccines take a COVID-19 polymerase chain reaction test weekly for 13 weeks.
The use of a PCR test would give researchers the ability to record positive cases whether an individual is presenting symptoms or not.
Following this period, the results were evaluated showing that out of 2,479 vaccinated persons, there were only three that tested positive for coronavirus.
The 477 that were only partially vaccinated had eight individuals test positive.
The study mentioned that there will be opportunities in the future to examine the structure of breakthrough infections that were able to bypass the vaccines’ defenses.
Although the study looked into the vaccine efficacy two weeks after administration, the actual time period between getting the vaccine and developing immunity is still unsure.
Since it’s been under a year from the initial vaccine rollout, there isn’t much data on how long the immunity from the vaccines will last.
UH College of Medicine clinical professor Bhavna Lall said that the continuation of this study would help clear up this uncertainty overtime.
“By gaining an understanding of the duration of these vaccines’ protection, this will also aid in understanding when we would potentially need booster vaccine doses, if needed,” said Lall.
Pfizer released data that indicated its vaccine showed continued immunity after six months in their study with over 46,000 participants. Health officials say that the protection is likely to last longer than that.
“Longer studies of the various vaccines will continue to give us information and evidence of safety and efficacy of these vaccines,” Lall said.
“These studies will also give better understanding of the duration of immunity from the vaccine and efficacy of the vaccines with the new circulating variants as well.”