From booster shots to FDA approval to efficacy against the delta variant and more, how do the COVID vaccines compare to each other and which is best for you?
There are various reasons why someone might choose a particular vaccine, but according to medical experts, the most important thing is getting vaccinated.
Still, it’s a question many ask as they prepare for their vaccination.
According to medical experts, the three vaccines currently available in the U.S. each offer protection.
Here’s a breakdown of what we know so far about each vaccine:
How effective are the COVID vaccines?
Vaccine efficacy has been a main question as the delta variant continues to spread around the country.
Health experts have said that a majority of hospitalizations and deaths associated with the variant in recent months are almost entirely in unvaccinated individuals. The CDC has said the risk of infection is 8x higher in the unvaccinated than the vaccinated, and the risk of hospitalization or death is 25x higher.
But is one better than the other at protecting against breakthrough infections in vaccinated populations?
The risk of suffering a breakthrough COVID-19 infection with the delta variant after being fully vaccinated with the Moderna vaccine may be much lower than the risk for those who received the Pfizer vaccine, according to a new Mayo Clinic study that is awaiting a full review.
The study found that in July in Florida, where COVID cases are at an all-time high and the delta variant is prevalent, the risk of a breakthrough case was 60% lower for Moderna recipients as compared to Pfizer recipients.
Similarly, in Minnesota last month, the authors found that the Moderna vaccine (also known as mRNA-1273) was 76% effective at preventing infection, but the Pfizer vaccine (known as BNT162b2) was 42% effective.
The authors of the study found that both vaccines “strongly protect” against severe disease; the difference appears to be more about whether people get infected at all in the first place. The so-called pre-print study, which has not gone through a peer review or been published in an academic journal, was first released earlier this month.
While Moderna’s two-dose vaccine remains “durable” six months after the second shot, immunity against the coronavirus will continue to wane and eventually diminish vaccine efficacy, the company said in slides that accompanied its second-quarter earnings report.
The company said its vaccine is 93% effective six months after the second dose. By comparison, Pfizer and BioNTech said their vaccine efficacy declined to around 84% after six months.
Johnson & Johnson reported last month that data showed their vaccine “generated strong, persistent activity against the rapidly spreading delta variant and other highly prevalent SARS-CoV-2 viral variants.”
“Current data for the eight months studied so far show that the single-shot Johnson & Johnson COVID-19 vaccine generates a strong neutralizing antibody response that does not wane; rather, we observe an improvement over time,” Dr. Mathai Mammen global head of Janssen Research & Development for Johnson & Johnson, said in a statement. “In addition, we observe a persistent and particularly robust, durable cellular immune response.”
Delta, the dominant form of the disease in the U.S., is more transmissible than the common cold, the 1918 Spanish flu, smallpox, Ebola, MERS and SARS, according to the Centers for Disease Control and Prevention.
How effective are the COVID vaccines?
In clinical trials, Moderna’s vaccine reported 94.1% effectiveness at preventing COVID-19 in people who received both doses. The Pfizer-BioNTech vaccine was said to be 95% effective.
A new CDC study reported that a single dose of Pfizer’s or Moderna’s COVID vaccine was 80% effective in preventing infections. That number jumped to 90% two weeks after the second dose, the study on vaccinated health care workers showed.
“These findings indicate that authorized mRNA COVID-19 vaccines are effective for preventing SARS-CoV-2 infection, regardless of symptom status, among working-age adults in real-world conditions,” the U.S. agency wrote in the study. “COVID-19 vaccination is recommended for all eligible persons.”
Pfizer’s vaccine, the only one currently authorized for use in children as young as 12, also showed heightened effectiveness among adolescents.
Pfizer in late March released preliminary results from a vaccine study of 2,260 U.S. volunteers ages 12 to 15, showing there were no cases of COVID-19 among fully vaccinated adolescents compared with 18 among those given dummy shots.
More intriguing, researchers found the kids developed higher levels of virus-fighting antibodies than earlier studies measured in young adults.
The FDA said J&J’s vaccine offers strong protection against what matters most: serious illness, hospitalizations and death. One dose was 85% protective against the most severe COVID-19 illness, in a massive study that spanned three continents — protection that remained strong even in countries such as South Africa, where the variants of most concern are spreading.
The CDC reports J&J/Janssen vaccine was 66.3% effective in clinical trials at preventing COVID-19 illness in people who had no evidence of prior infection 2 weeks after receiving the vaccine.
“The vaccine had high efficacy at preventing hospitalization and death in people who did get sick,” the CDC notes. “No one who got COVID-19 at least four weeks after receiving the J&J/Janssen vaccine had to be hospitalized.”
It is not known if any of the three vaccines prevent the spread of the virus by people who are asymptomatic, though the CDC noted that “early evidence suggests that the J&J/Janssen vaccine might provide protection against asymptomatic infection.”
While the overall effectiveness data may suggest the J&J candidate isn’t quite as strong as the two-dose Pfizer and Moderna options, all of the world’s COVID-19 vaccines have been tested differently, making comparisons nearly impossible, CNBC reported.
“If you kind of do a comparison for influenza vaccines, which we do annually, influenza’s efficacy can range anywhere from 40% to 60% – and that’s a good year,” Monica Hendrickson, public health administrator for the Peoria County Health Department said last month. “So again, something that’s high public health was, you know, we were hoping for something above 40%. To get to 95%, even 65%, that’s a homerun.”
According to the Illinois Department of Public Health, “the best COVID-19 vaccine is the first one that is available to you.”
“Clinical trials have found the vaccines to be 100% effective in preventing hospitalizations and deaths,” the department’s website states.
Will a booster shot be needed?
U.S. health authorities are now recommending an extra dose of the COVID-19 vaccine for all Americans eight months after they received their second dose of the Pfizer or Moderna shot.
In a joint statement, the directors of the Centers for Disease Control and Prevention, Health and Human Services, the National Institute of Health and other top medical experts, outlined plans to begin administering booster shots later next month.
The overall plan is pending a Food and Drug Administration evaluation of the safety and effectiveness of a third dose, the officials said.
Those who were fully vaccinated earliest, which includes health care workers, nursing home residents and other older people, will be first in line to get a booster shot before they are available to the general public.
U.S. regulators already authorized an extra dose of the Pfizer or Moderna COVID-19 vaccines for people with compromised immune systems earlier this month. The U.S. Centers for Disease Control and Prevention advisory panel also recommended the extra shot for those individuals.
The announcement applies to several million Americans who are especially vulnerable because of organ transplants, certain cancers or other disorders and who received the Moderna or Pfizer COVID vaccines.
According to the CDC, the list includes people who have:
- Been receiving active cancer treatment for tumors or cancers of the blood
- Received an organ transplant and are taking medicine to suppress the immune system
- Received a stem cell transplant within the last 2 years or are taking medicine to suppress the immune system
- Moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome)
- Advanced or untreated HIV infection
- Active treatment with high-dose corticosteroids or other drugs that may suppress your immune response
The agency notes that “people should talk to their healthcare provider about their medical condition, and whether getting an additional dose is appropriate for them.”
People who received the one-shot Johnson & Johnson vaccine will also likely need a booster shot, but more information is needed because the U.S. didn’t begin administering it until March 2021, officials said.
Health officials are expecting to receive more data “in the next few weeks” and will “keep the public informed with a timely plan for J&J booster shots as well.”
The FDA and CDC’s approval and recommendation for immunocompromised individuals does not apply to those who got the Johnson and Johnson vaccine.
How are the vaccines different?
Arguably one of the biggest difference between the three vaccines is the number of doses needed. The Johnson & Johnson vaccine requires just one dose, while both Pfizer’s and Moderna’s vaccines are two shots.
The Pfizer-BioNTech and Moderna vaccines also differ from traditional vaccines in their use of mRNA. Instead of introducing a weakened or an inactivated germ into your body, this vaccine injects mRNA, the genetic material that our cells read to make proteins, into your upper arm muscle. It teaches your body how to make the protein that triggers antibody production so if the real virus later enters your body, your immune system will recognize it, according to the federal Centers for Disease Control and Prevention.
Unlike the Pfizer and Moderna shots, the J&J vaccine uses a cold virus, called an adenovirus, to carry the spike gene into the body. J&J uses a human adenovirus to create its vaccine while a similar vaccine not yet approved in the U.S., AstraZeneca, uses a chimpanzee version.
J&J’s shot uses a cold virus like a Trojan horse to carry the spike gene into the body, where cells make harmless copies of the protein to prime the immune system in case the real virus comes along. It’s the same technology the company used in making an Ebola vaccine.
Does age matter for vaccinations?
Pfizer’s vaccine is also currently the only vaccine authorized for emergency use in children as young as 12. Both Moderna and J&J’s vaccines can only be used on people 18 and older.
What about younger kids? According to experts, those under 12 likely won’t be able to receive the COVID vaccine until later this year or early next year.
Both Pfizer and Moderna have started studies in the U.S. surrounding the vaccine and children ages 6 months to 11 years. Results on those studies could come sometime in the fall.
What are the side effects for each vaccine?
According to Pfizer, about 3.8% of their clinical trial participants experienced fatigue as a side effect and 2% got a headache. The side effects remain similar among young adults and adolescents.
Younger teens receive the same vaccine dosage as adults and have reported the same side effects, mostly sore arms and flu-like fever, chills or aches that signal a revved-up immune system, particularly after the second dose. However, the CDC is also looking into rare reports of mild myocarditis in some younger recipients, though it remains unclear if the condition is in fact linked to the vaccine.
Moderna says 9.7% of their participants felt fatigued and 4.5% got a headache.
Like Pfizer and Moderna’s COVID-19 vaccines, the main side effects of the J&J shot are pain at the injection site and flu-like fever, fatigue and headache. These side effects usually start within a day or two of getting the vaccine, according to the CDC.
But the Johnson & Johnson vaccine was previously paused by U.S. regulators as they investigated reports of potentially dangerous blood clots known as cerebral venous sinus thrombosis, or CVST, in a small number of recipients.
The CDC and FDA said in April they were investigating unusual clots in six women that occurred 6 to 13 days after vaccination. All six cases were in women between the ages of 18 and 48. At the time, more than 6.8 million doses of the J&J vaccine had been administered in the U.S., the vast majority with no or mild side effects.
Ten days later, the agencies recommended resuming use of the vaccine, stating the benefits of the inoculations outweighed their risks.
The CDC’s advisory panel didn’t recommend restricting use of the vaccine to a particular age or gender, but did propose the possibility of adding a warning label for women under the age of 50.
There have also been reported cases of a rare, but serious, neurological disorder following Johnson & Johnson COVID-19 vaccinations, but preliminary data suggests the benefits of the shots still outweigh the risks, the Centers for Disease Control and Prevention said last month.
As of late last month, there were 8.1 cases of Guillain-Barre syndrome per 1 million doses, which is higher than expected in the general population and close to eight times the rate seen in Pfizer’s and Moderna’s shots, according to slides published ahead of a presentation before the CDC’s Advisory Committee on Immunization Practices. Guillain-Barre is a rare neurological disorder in which the body’s immune system mistakenly attacks part of the nervous system.
The data doesn’t show a similar pattern with Pfizer‘s or Moderna‘s vaccines, the U.S. agency said. By comparison, there has been roughly one case of Guillain-Barre per million doses for people who received either of the two-dose mRNA vaccines, according to the agency.
Rare side effects, which scientists say are common, have also been detected in Pfizer’s and Moderna’s vaccines.
In late June, the FDA added a warning to patient and provider fact sheets for the mRNA vaccines to indicate a rare risk of heart inflammation. Both vaccines now include a warning about myocarditis and pericarditis after the second dose. Myocarditis is the inflammation of the heart muscle and pericarditis is the inflammation of the tissue surrounding the heart. Health officials said the benefits of receiving the vaccines still outweigh any risk.
The CDC reports the most common side effects for all three authorized vaccines is at the injection site. They include:
- Pain
- Redness
- Swelling
Common side effects in the body include:
- Tiredness
- Headache
- Muscle pain
- Chills
- Fever
- Nausea
“The Pfizer-BioNTech COVID-19 Vaccine and Moderna COVID-19 Vaccine both need 2 shots in order to get the most protection,” the CDC states. “You should get the second shot even if you have side effects after the first shot, unless a vaccination provider or your doctor tells you not to get it.”
The Centers for Disease Control and Prevention advises people to stick around for 15 minutes after vaccination, and those with a history of other allergies for 30 minutes, so they can be monitored and treated immediately if they have a reaction.
Are side effects more likely after the first or second dose?
With the two-shot vaccines, people are more likely to report side effects after their second dose, experts have said.
According to the CDC, side effects after your second shot “may be more intense than the ones you experienced after your first shot.”
“These side effects are normal signs that your body is building protection and should go away within a few days,” the CDC states.
In trials of both the Moderna and Pfizer vaccines, more people experienced side effects after the second dose.
But that doesn’t mean that you shouldn’t get your second shot if you get side effects after your first, experts say.
“When people receive that second dose, they are receiving the second booster to try and reach the maximum efficacy,” said Dr. Edward Cachay, infectious disease specialist at UCSD.
The CDC also noted that both shots are needed.
“The Pfizer-BioNTech COVID-19 Vaccine and Moderna COVID-19 Vaccine both need 2 shots in order to get the most protection,” the CDC states. “You should get the second shot even if you have side effects after the first shot, unless a vaccination provider or your doctor tells you not to get it.”
What about side effects with booster shots?
The CDC stated that side effects with the third shot “were similar to that of the two-dose series.”
The most common symptoms include fatigue and pain at the injection site, but “most symptoms were mild to moderate.”
As with previous doses of the vaccine, the CDC notes that, “serious side effects are rare, but may occur.”
Are the COVID vaccines FDA approved?
The Food and Drug Administration on Monday granted Pfizer and BioNTech full U.S. approval of their COVID-19 vaccine – becoming the first in the U.S. to win the coveted designation.
Up until now, Pfizer’s mRNA vaccine was on the U.S. market under an Emergency Use Authorization, which was granted by the FDA in December.
The companies submitted a Biologics License Application to the FDA on May 7 for patients age 16 and up. That application was approved Monday.
The vaccine is also still available under emergency use authorization (EUA) for younger people ages 12 through 15 and for a third booster dose in those with compromised immune systems, the FDA said.
While Pfizer is currently the only vaccine to be fully approved, it is also the only vaccine authorized for emergency use in adolescents between the ages of 12 and 17, though Moderna filed for such approval earlier this year.
Emergency use authorization allows a vaccine to become available prior to full approval in the case of public health emergencies. The FDA can revoke the EUA at any time.
Moderna’s two-shot and Johnson & Johnson’s single-shot vaccines continue to be available under an emergency use authorization as well.
Moderna also announced in June that it had begun a “rolling submission” to the FDA of data from its studies of the two-dose mRNA vaccine.
“We are pleased to announce this important step in the U.S. regulatory process for a Biologics License Application (BLA) of our COVID-19 vaccine,” Moderna CEO Stephane Bancel said in a press release at the time. “We look forward to working with the FDA and will continue to submit data from our Phase 3 study and complete the rolling submission.”
Large-scale studies of the shots continued after Moderna’s emergency authorization. The FDA will scrutinize the information to see if the vaccine meets stringent criteria for full licensure.
from NBC Chicago https://ift.tt/2WeNpQT
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