As COVID-19 vaccine distribution ramps up, so might the likelihood of Americans actually getting to choose which vaccine they receive when eligible. While all three vaccines cleared for emergency use perform extremely well against hospitalizations and deaths, there are some key differences.
The two-dose Pfizer-BioNTech and Moderna vaccines are messenger ribonucleic acid (mRNA) vaccines. The mRNA is like a set of instructions for your cells to create a piece of the “spike protein” that’s unique to COVID-19. This spike protein stimulates the creation of antibodies that protect you against COVID-19. It doesn’t contain the live virus or inactivated viral particles. And it cannot give you COVID-19.
The one-dose Johnson & Johnson (J&J) vaccine works by distributing DNA – rather than mRNA – into your cells. This DNA is encased in inactivated adenovirus. Because these adenovirus particles are inactive, they can’t make you sick. Like mRNA, this DNA provides your body with instructions on how to create that same spike protein used to fight off COVID-19.
The Pfizer and Moderna vaccines are more than 95% effective at preventing mild to moderate disease. The J&J is 72% effective in U.S. studies. When you compare those percentages, it’s easy to understand some people’s concerns and hesitancy over getting the “less effective” vaccine. But when it comes to preventing hospitalizations and deaths, studies indicate that all three vaccines are nearly perfect with 100% efficacy.
J&J is currently conducting a two-dose trial, which could further boost its efficacy against mild to moderate disease. But its current one-and-done approach to vaccination is a huge selling point for:
• College students who may soon be leaving for school
• Employees who travel for work or have jobs that don’t allow flexibility when it’s time for a second shot
• Individuals who lead busy lives, or those who’ve already been diagnosed with COVID-19 and may have already acquired some natural immunity
• People with an aversion to needles
In trials, the J&J vaccine showed a strong immune response after just one dose, but evidence also suggests this: That immune response may actually continue increasing well after recipients are considered fully vaccinated – two weeks after the shot. While that evidence doesn’t necessarily make J&J’s vaccine superior to others, it should provide peace of mind to those who’ve been hesitant about a one-dose vaccine.
If, however, you’re in the camp that thinks one less dose means you’re less likely to develop vaccine side effects, think again. Many J&J vaccine recipients have reported side effects similar to those associated with mRNA vaccines. Those side effects include:
• Chills and/or fever
• Muscle aches
• Pain, redness or swelling at the injection site
Remember: Experiencing side effects is a good thing! It’s a sign that your immune system is fighting off what it sees as foreign and harmful.
Keep in mind: There are ways to help minimize some of those side effects. Plan ahead if you can. Take the day off of work after your vaccination or plan to get vaccinated on a Friday. Don’t let the threat of possible side effects delay you from getting vaccinated.
The J&J vaccine trials were conducted at a different time than the mRNA trials – much later in the pandemic, when there were greater numbers of infections and the presence of variant strains (which seem to be more contagious). Would the Pfizer and Moderna vaccines do as well under similar circumstances? We don’t know. Are the mRNA vaccine efficacy numbers truly greater even though they were done early in the pandemic with fewer infections and no variant strains? Again, we don’t know. While it’s believed that all three vaccines provide some level protection against COVID-19 variants, the difference in trials may tell us less about how well the mRNA vaccines hold up against them.
It goes without saying, but timing and the prevalence of variants play important roles in determining vaccine efficacy.
So, what vaccine do I recommend? All of them. But the best vaccine is the one you’re offered first. Don’t think that if you wait longer, the vaccine you want will eventually become available. That’s not a guarantee, and it’s a rather dangerous gamble.
The sooner everyone gets vaccinated, the sooner we can prevent more serious infections, more deaths and the emergence of additional variants. We’re absolutely in the home stretch, but we need everyone’s participation and now.