As the number of COVID-19 cases and hospitalizations rise across Illinois, how can the vaccine protect you, and which one is best?
At this point, it appears vaccine are working to prevent severe illness and death even from the omicron variant, but waning immunity has led to the need for boosters.
And with each new variant, there's a rush to figure out whether current vaccines can combat it.
There are various reasons why someone might choose a particular vaccine, but according to medical experts, the most important thing is getting vaccinated and getting a booster dose.
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Here's a breakdown of what we know so far about each vaccine:
How are vaccines performing against the omicron variant?
Health experts say being vaccinated can be the difference between getting COVID and being hospitalized or dying from COVID, but beyond that, symptoms can also vary depending on your vaccine.
Chicago Department of Public Health Commissioner Dr. Allison Arwady previously said that data showed both the Pfizer and Moderna vaccines were performing better than Johnson & Johnson's vaccine at preventing breakthrough infections, but all three protect against hospitalization and death.
Last month, the CDC's Advisory Committee on Vaccine Practices unanimously recommended Pfizer and BioNTech's or Moderna's COVID-19 vaccines, which use mRNA technology that hasn't been linked to the blood clots, over J&J's, which uses a more traditional virus-based technology.
Real-world data from the United Kingdom has shown that Pfizer's and Moderna's vaccines are only about 10% effective at preventing symptomatic infection from omicron 20 weeks after the second dose, according to study from the U.K. Health Security Agency. However, the original two doses still provide good protection against severe illness, the study found.
Booster shots are up to 75% effective at preventing symptomatic infection, according to the study.
While breakthrough infections are seemingly on the rise across all vaccines, cases in fully vaccinated and boosted individuals appear to be milder compared to unvaccinated patients, experts said.
"If [fully vaccinated people] get COVID, as opposed to getting seriously ill and having fevers for days and difficulty breathing, etc., they may only experience it as a mild illness," Arwady said. "They may only feel like they have a cold. That's good because they're not getting seriously sick. They're not threatening the healthcare system, but it's certainly of some concern because they do have the potential to transmit to others."
What about booster shots?
Health officials are now strongly encouraging booster shots of all three COVID vaccines for any U.S. adult.
Last month, the CDC cleared the way for all adults to get a COVID-19 booster shot, if they want one. But now, with the omicron variant, the CDC has intensifyied that message — saying those over 18 years old should get one.
"Everyone ages 18 and older should get a booster shot ... when they are six months after their initial Pfizer or Moderna series," CDC Director Dr. Rochelle Walensky said in a previous statement.
"The recent emergence of the omicron variant (B.1.1.529) further emphasizes the importance of vaccination, boosters, and prevention efforts needed to protect against COVID-19," she added.
In Illinois and Chicago, officials continue pushing for residents to get vaccinated against COVID-19 and get their booster shots as soon as they are eligible, meaning six months after Moderna or Pfizer's vaccine or two months after the Johnson & Johnson vaccine.
"I don't have the answers out of whether an omicron booster will be needed, but what I do know is that getting the vaccines we have now and getting boosted has helped protect against the spread of omicron in a number of case examples," Arwady said.
Pfizer has said that a booster dose of its COVID-19 vaccine may offer important protection against the new omicron variant even though the initial two doses appear significantly less effective.
Both Pfizer and Moderna have said they are working on omicron-specific vaccines that could be used as booster doses against the new variant.
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 CDC.
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 5. Both Moderna and J&J's vaccines can only be used on people 18 and older.
Both Pfizer and Moderna have also started studies in the U.S. surrounding the vaccine and children as young as 6 months.
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.
Children as young as 5 are experiencing less side effects overall, according to Dr. Jackie Korpics with Cook County Health. But when children do encounter side effects, they're typically similar to the ones experienced by adults and usually after the second dose, too.
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 CDC said.
As of late July, 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 University of California San Diego.
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 FDA has 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.
The companies submitted a Biologics License Application to the FDA on May 7 for patients age 16 and up. That application was approved in August.
The vaccine is also still available under emergency use authorization (EUA) for people as young as 5.
While Pfizer is currently the only vaccine to be fully approved, it is also the only vaccine authorized for emergency use in adolescents and children, though Moderna has also filed for such approval.
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 for those over the age of 18.
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.
