This was written in December 2021. Top-of-mind topics and the amount we're learning is continuously changing, as you know. We like to leave these articles active for reference, but please review newer Kinsa articles for the most up-to-date information!
We know that squeezing in yet another vaccine can be a hassle...but Kinsa’s team of epidemiologists likes to think of COVID boosters as a bonus gift this holiday season.🎁 We know that the messaging surrounding boosters has been confusing, so we wanted to break down what the deal is: if you should get a booster (spoiler: yes), which to choose, and why it’s more important now than ever with Omicron entering stage-left.
First things first: the CDC recommends that everyone 5 years and older should receive a COVID booster shot 2 months after a two-dose Pfizer or Moderna series. COVID vaccines are free to everyone in the US, regardless of insurance status. You can get the booster shot at most major pharmacies, as well as doctor offices or local vaccine clinics - find a vaccine near you here. If you want to be really efficient, you can schedule your flu vaccine and COVID booster at the same time.
It’s safe and effective to mix ‘n match your booster with whichever original shot you got, which means you can get any of the three vaccines as boosters. Ah, but which to choose? Preliminary data suggests that either mRNA booster (Moderna or Pfizer) produces a greater antibody response than J&J, so we’ve personally opted for one of those. There’s some evidence that mixing and matching your mRNA shots may provide a marginal protective benefit - but if you were happy with your first series, there’s likely no need to change things up. If you have any specific concerns, especially if you’re immunocompromised, it’s a good idea to chat with your healthcare provider.
Side effects vary person-to-person and shot-to-shot, but be prepared for some short-term symptoms similar to the first series of shots, including some pain/soreness at the injection site, fever, headache and fatigue.
Now for why we know all too well that getting a COVID booster is a good idea (2 minute version):
(1) Waning antibody immunity: it’s expected that neutralizing antibodies - our fastest acting defensive line against viruses - decrease over time, which is what we’re now seeing play out with COVID vaccine recipients. Booster shots act to splash some cold water on your immune system’s face: they restimulate the immune response and generate even higher levels of antibodies than were originally produced! Yes, these guys will fade too, but to higher levels than their previous baseline, better protecting you from the next possible viral attack.
(2) Increased protection from Delta infection: how does this play out in the real world? Recent research found folks with boosters were 86% less likely to get a COVID infection for at least two months following the booster shot, compared to those who had only received their initial vaccine series. Now, those are odds I’d put some money on.
(3) Increased protection from Omicron infection: as you’ve likely read, the Omicron variant’s many mutations, including in the spike protein (a.k.a. main vaccine target), are worrisome because they may potentially allow Omicron to evade existing immunity from vaccines. We can now share some preliminary lab findings that answer these questions, but it’s important to note that things may play out differently in the real world.
- Preliminary lab data shows a 25-40 times reduction of neutralizing antibody response against Omicron, compared to the original virus strain.
- But don’t fret just yet - there’s good news too. Early lab data from Pfizer suggests that booster shots may increase the antibody response against Omicron to levels comparable to the original strain.
- More good news: the immune response from vaccination is more robust than stimulating our much-discussed antibodies. T-cells are a type of white blood cell that can recognize parts of viruses and either directly attack them or recruit other cells to finish the job. Your original vaccine (especially when assisted with a booster) helps train T-cells, who aren’t as easily "fooled" by Omicron's mutations. This means they can protect you from becoming severely sick even if you are infected.
COVID cases continue to crescendo countrywide, which means that the risk of encountering the virus as you go about your daily life increases too. While boosters are not a magic bullet to end this pandemic, they can certainly help reduce your risk of infection and of severe disease.