By Tania Hassan | Staff Writer
While it seems like only yesterday that people were calculating the date they could feel fully protected by their vaccination, now boosters are being recommended for wider swaths of the community. Recently, the FDA authorized boosters for millions of people who received the Moderna, Johnson & Johnson, and Pfizer vaccines. The CDC recommended it too. Consequently, many questions come to mind; what do we know about those third doses of the vaccine so far? Are they safe and effective? Who needs them? And should the world be looking at booster shots at this stage of the pandemic?
A booster is just another dose of a vaccine you received. You take it to prolong protective immunity, particularly if there is evidence that protection is waning after some time. While a booster sometimes is a replica of the initial vaccine, it can also be tweaked. With COVID-19, this is key because the vaccine could then be tailored to target particular variants of the virus. For instance, there is some evidence that immunity against COVID-19 does wane, especially against the delta variant. Researchers have found that a single dose of either the Oxford-AstraZeneca or Pfizer-BioNTech vaccine is only around 30% effective against delta, and two doses are more effective: 88% for Pfizer and 67% for AstraZeneca. Hence, the booster conversation is gaining urgency as we watch the Delta variant surge among unvaccinated individuals, and health officials around the world report growing numbers of breakthrough cases in fully vaccinated individuals which, although tend to be asymptomatic or mild, are of growing concern.
Nevertheless, the booster vaccine is still not being recommended for the whole vaccinated community. Currently, Pfizer and Moderna boosters are recommended for people that are at least 65 years old, as well as younger adults with health problems, high-risk jobs, or other situations that put them at high risk of contracting the virus. The doses are for those who received their second shot at least six months ago as research has found that protection remains high for six months after the second shot of a Pfizer or Moderna vaccine. For example, per the last email sent by AUB Vaccination Working Group, AUBMC started administering the third Pfizer dose to the following groups of individuals: anyone who is 60 years and above, including all AUBMC faculty and staff, given that they have received the second vaccine dose before May 15, 2021 and did not test positive for COVID-19 after that date. Pfizer’s third booster dose is the same formulation and the same strength as the first and second shots.
When it comes to symptoms, data collected suggests that the side effects brought on by the booster are very similar to the symptoms some people experienced after the initial set — possibly even milder. Pain at the injection site was the most commonly reported reaction after receiving the booster, according to the clinical trial data Pfizer and BioNTech submitted to the U.S. Food and Drug Administration (FDA). About 83 percent of the trial’s booster recipients reported it, followed by fatigue (63.7 percent) and headache (48.4 percent), most of which were mild to moderate.
The main concern leaping through everyone’s mind now is, might we need annual COVID-19 vaccinations? This is certainly a possibility, said Anthony Harnden, a member of the Joint Committee on Vaccination and Immunization. “I suspect it’s going to be likely that we’re going to require an annual boost for a while . . . It just depends on the length of duration of protection. The virus mutates, [but it] probably doesn’t mutate as much or as quickly as the influenza virus, so it’s very difficult to predict whether this is going to be an annual vaccine or for how many years.”, he said.
Moreover, as boosters are being administered, mixing and matching between vaccines have happened. That confused many people about what vaccine to take next. So-called “mixing and matching” of vaccines has been used in Europe and other places, particularly when there were supply issues. Additionally, there have been studies suggesting this approach—with one dose of AstraZeneca’s vaccine and one dose of Pfizer’s vaccine—may even offer more vigorous protection. If you’re not sure which booster to get, talking to a physician who can take into account your specific circumstances is recommended. While serious side effects from vaccination are highly uncommon, a very small number of women under 50 have developed serious blood clots after receiving the Johnson & Johnson shot, while in rare cases the mRNA-based vaccines have been associated with heart issues in young people, especially young men and teenage boys. If you fall into one of those demographics, your doctor may advise you to choose a different shot for your booster, just to be extra safe.
We are all interdependent and we can see that many of the new variants are originating from unvaccinated areas, which certainly speaks to the importance of the vaccine, especially to drive down infection rates that support the emergence of new variants. So, although a third dose of the vaccine can provide a strong boost to the immune response, the “urgent priority” should be to ensure that people around the world get their first dose.
Finally, “The booster question is being worked out as we speak,” Dr. Albert Shaw, Yale Medicine infectious diseases expert, says, noting that the open possibility of the need for a booster shot doesn’t represent a failure of the existing vaccines. “People get confused—or they think something is wrong—when guidance changes with COVID-19, but we have to remember that we are learning about this as we go.”