- The first COVID-19 vaccine was authorized for use by the FDA this month, and a second vaccine made by Moderna may be authorized as soon as Friday.
- But even with these authorizations, there are lingering questions about the vaccine, such as how effective it’ll be in the real world and how long it’ll offer protection.
- We talked to experts about the questions they still have about the vaccine and when we might have answers.
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Since the early days of the pandemic, Operation Warp Speed was launched to help create a COVID-19 vaccine as quickly and as safely as possible.
On Dec. 14, the Pfizer-BioNTech vaccine was the first approved by the Food and Drug Administration (FDA) for emergency use authorization (EUA), which would allow millions of people to get vaccinated.
Despite this breakthrough, there are still some lingering questions about the vaccine and the road ahead. We try to provide answers to 10 of these questions.
The Pfizer vaccine trial has over 37,000 participants, the majority of which are in the United States. Over 18,000 received a vaccine and a similar number of people were given a placebo.
Although enough data has been collected for EUA, many experts believe that the trials will still go on, particularly with these original participants.
This allows for long-term monitoring of side effects of the vaccine beyond the initial monitoring period used for FDA approval.
“Although many of the steps for authorization have been accelerated, the public should be totally confident that none of the science steps along the way have been compromised,” Henry Bernstein, DO, pediatrician at Cohen Children’s Medical Center in Queens, New York, and a member of the
“As a result, the scientific integrity is clear, and these vaccine studies will continue to gather ongoing data,” he said.
With the speed at which this vaccine was approved, from enrollment to acceptance, there’s no clear information on how long this vaccine is going to be effective.
The virus was only just discovered at the end of 2019.
Based on Moderna’s and Pfizer’s clinical trials, which both started at the end of July, experts have been able to show that the vaccines have long-lasting protection, but the actual length of time is still unknown.
However, with the data that’s available, research shows continued protection since the start of the trial, and further monitoring of trial participants in the months and years to come will allow for understanding of long-term immunity.
Although there’s a strong protection against COVID-19 after receiving the vaccination, there’s still a chance that one could get the virus after being vaccinated.
The vaccine takes time to provide protection, and no vaccine is perfect.
The Pfizer vaccine is said to be 95 percent effective, according to evidence released by regulators. The Moderna vaccine appears to be about 94 percent effective.
But even after getting these vaccines, it may take several weeks for the body to start building immunity after the vaccination. This means that someone could get sick with the virus just before or even just after getting the vaccination.
With an initial limited supply of the COVID-19 vaccine, only certain groups are being allowed to be vaccinated.
“Based on current projections, healthy people under the age of 65 with no medical conditions that put them at higher risk for COVID-19 complications, and who are not in one of the other priority categories (healthcare worker, essential worker, first responder) can probably expect to start getting their vaccinations by early spring, late March through April,” Dr. Aadia Rana, associate professor of medicine in the University of Alabama-Birmingham’s Division of Infectious Diseases, told Healthline,
Vaccine manufacturers are working quickly to produce and ship it quickly. Many companies are working to ensure that this vaccine can arrive at the points of use as quickly and safely as possible.
“So much will depend on any disruptions in the supply chain for the materials needed to make the vaccine,” Rana said. “If there are any disruptions in the materials, that timeline may be delayed.”
The COVID-19 vaccine trial that was being completed by several companies didn’t include pregnant people.
Historically, drug and vaccine makers tend to be reluctant to include pregnant people in initial clinical trials for fear of threatening a pregnancy.
Studies in pregnant people are planned despite the American College of Obstetricians and Gynecologists (ACOG) advocacy for inclusion in the initial trials.
However, data from animal developmental and reproductive toxicity studies (DART) are ongoing, and studies in people are being planned.
“At this time, we do not believe there is any reason to be concerned in pregnant women. We encourage pregnant women to talk with their OB [obstetrician] if they have any questions or concerns,” said Dr. Keipp Talbot, associate professor of medicine in the Division of Infectious Diseases at Vanderbilt University Medical Center.
Many experts warn that having COVID-19 during pregnancy may be worse than any potential outcome of the mRNA vaccine that has recently received emergency authorization from the FDA.
“While there are no currently available data on the vaccine’s safety in pregnant women,” Bernstein said, “I believe pregnant women should know that the mRNA vaccine is not a live vaccine and it is degraded quickly by a normal cellular process. As a result, it does not enter the nucleus of the cell, nor alter its DNA.”
Rana also supports people who are pregnant getting the vaccine.
“There is a reported increased risk of severe illness including ICU [intensive care unit] admission, mechanical ventilation, and death among pregnant women with COVID-19,” she said.
“A pregnant woman should discuss vaccine options with her healthcare provider to help make an informed decision,” Rana said. “This would include considerations for her risk of acquisition based on current community transmission rates and her occupation (e.g. healthcare worker) or other potential exposures, versus the known side effects of the vaccine and the lack of data about the vaccine during pregnancy.”
Much of the data collected is still new, and pharmaceutical companies didn’t specifically include people who were planning on becoming pregnant in their clinical trials.
Therefore, there’s no human data to suggest vaccine safety in people who are planning to become pregnant.
As a result, there’s not a formal recommendation in the United States for families who are looking to become pregnant.
Among the participants of phase 2 and phase 3 clinical trials, several people have subsequently become pregnant and, according to ACOG, these people are being followed to collect safety outcomes.
Many in the United States are advocating for people who are already pregnant to get vaccinated.
On the other hand, the United Kingdom’s Joint Committee on Vaccination and Immunisation warns that “women should be advised not to come forward for vaccination if they may be pregnant or planning a pregnancy within 3 months of the first dose.”
With the trials that have been conducted, data regarding lactating people and the COVID-19 vaccine has not formally been studied.
According to the
Both the Pfizer and the Moderna vaccines are of the mRNA type, and thought not to pose a risk to a breastfeeding baby.
Talbot recommends breastfeeding people to be vaccinated as “the vaccine contents should not be found in the blood and hence not the milk.”
Although many believe that life will be back to normal after they are vaccinated, this is not entirely the case.
Vaccines are not 100 percent fail-proof, and individual vaccination isn’t the only part of the greater community effort to curtail the COVID-19 pandemic.
“Until we have 70 to 80 percent of individuals being vaccinated, there will still be large susceptible populations who are at risk for morbidity and mortality from the virus,” Bernstein said.
Also, these vaccination trials showed prevention only against symptomatic disease.
“[The trials] were not designed to look at the impact of asymptomatic infection,” Rana said. “And as we all know, asymptomatic people can still transmit disease.”
The current recommendation advises that those who have already had COVID-19 still get the vaccine.
While natural infection with the virus gives you some degree of immunity, it doesn’t give you full protection.
Vaccines are specifically created to neutralize the virus and its ability to infect.
Also, there have been reported cases of people who’ve had COVID-19 developing the disease a second time.
By having the vaccine, repeat infection of COVID-19 is greatly reduced and can assist in infection prevention in those that are most vulnerable.
The participants in clinical trials got the COVID-19 vaccine at the end of July, and emergency authorization of the vaccine was granted in December.
In light of this, it’s unknown how long immunity will last with these vaccines.
Participants of the initial clinical trials are still being monitored, so we only have data since that time.
The new vaccine requirements for influenza have more to do with the changing nature of the virus strains that caused disease.
However, there doesn’t seem to be varying strains of COVID-19.
“We have no evidence right now of clinically relevant differing strains of SARS-CoV-2, the virus that causes COVID-19,” Rana said. “The available data shows lasting immunity of almost 120 days, and we hope to get more evidence as more time passes.”