By Angelina Campanile

The Centers for Disease Control and Prevention now recommend immunocompromised individuals to receive a fourth dose of the COVID-19 vaccine three months after their first booster shot.

The CDC also published new reports comparing the booster’s efficacy against COVID-19 to people who are unvaccinated and vaccinated but not boosted.

Here’s what they found:

So what is a booster shot anyway and why does it make a substantial difference in the fight against COVID-19? Dr. Maggie Collison, Infectious Disease at NorthShore, answered common questions about the booster:

Q: What exactly is a booster shot and how does it work?
A: The booster is an additional dose of the COVID-19 vaccine that helps reduce the risk of infection by giving your body a wake-up call to build stronger immunity against the virus. It’s another way of your body seeing the virus without actually contracting it. That way if you catch the actual virus, your body will be familiar with it. Your body will say, “Hey I’ve seen this particle before, I know exactly what to do.” 

Q: Does the booster offer protection against contracting the virus or simply against severe symptoms?
A: If you’re unvaccinated, you’re 13 times more likely to test positive for COVID and 68% more at risk of dying from COVID. Being vaccinated with the booster won’t 100% prevent you from contracting the virus, but it’s still very much working to prevent you from needing to be hospitalized due to COVID-19 complications. 

Q: Why should I get boosted? Is it not enough to be fully vaccinated?
A: When it comes to most viruses and COVID especially, we now know that your antibodies decrease over time. Getting those antibodies boosted and more recently exposed to the virus is crucial, especially during the winter when we’re indoors and the virus spreads more easily. The booster gives that extra reminder to the body to be on the lookout for the virus, that way it’s freshly prepared and knows how to fight back when it needs to. 

Q: What is the most common misconception you’ve heard about the COVID vaccine?
A: The biggest myth I’ve heard is that you’ll get COVID-19 from the vaccine. This is not true. You cannot get COVID from the vaccine because the vaccine only gives you a piece of the virus, not the fully coded thing. A lot of patients say they rather get COVID because they know they won’t feel well after the vaccine. My response is that this is an incredibly unpredictable virus. The side effects from the vaccine, like muscle aches and fever, will surely outweigh being hospitalized and possible death from contracting the actual virus. 

Q: What other types of vaccines besides COVID-19 require periodic boosters?
A: We get several periodic boosters as kids and even as adults. Some examples are measles, mumps, rubella, and tetanus. There are multiple series of shots so your body is best prepared and reminded how to fight the virus. 

Q: Why do we need boosters for some vaccines but not others?
A: Whether or not you need a booster depends on the bacteria or virus itself, and how our immune system responds to them. For example, one shot can give you lifelong immunity from chickenpox but you can get the flu if you don’t get your yearly flu shot. This is because flu strains change so frequently. 

Q: We’ve seen the coronavirus shapeshift into three different mutations now. Do you think COVID will end up like the flu where we have different strains every year and yearly shots to fight those particular strains? 
A: A virus naturally wants to keep moving. When the virus replicates, it can make mistakes. You’ll still have protection from your last vaccine, but there is a possibility that it may not be as strong fighting against those new mutations. I think it depends on whether or not we can decrease transmission. If we do that, the virus won’t have as many opportunities to mutate.

Q: What advice do you have for people who are hesitant to receive the COVID-19 booster?
A: The booster is a huge layer of protection for ourselves and for our community. I strongly encourage you to ask your healthcare provider about it and do your best in protecting yourself and others around you by getting the vaccine.