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There Are Three COVID Vaccines Now and They're All Good

a hand holding a vaccine vial
Credit: Phill Magakoe / AFP - Shutterstock

This weekend, the FDA authorized another vaccine for COVID-19, bringing the total number of options in the US up to three. While there are subtle differences between the three vaccines, all of them appear to be safe and effective, and experts recommend that you get whichever one you can.

What’s the new vaccine?

The new addition is the Johnson & Johnson/Janssen vaccine. Unlike the previous vaccines, this one requires only one dose, not two, and it can be stored and shipped at refrigerator temperature. Both of these features make it more convenient to administer.

While the Pfizer and Moderna vaccines were based on mRNA, the J&J one uses a different new technology. Instead of RNA inside a lipid bubble, it delivers DNA inside a harmless virus (an adenovirus modified so that it cannot replicate).

This scrap of DNA doesn’t modify your actual genome. It just floats around for a little bit before it’s destroyed. In the meantime, your cells read it; it contains a recipe for the coronavirus spike protein. We make the spike protein, which triggers an immune response.

While this type of vaccine is new, it’s not the first of its kind. J&J has made an Ebola vaccine, authorized in Europe last year, with the same technology.

Is it less effective?

This vaccine had a lower efficacy result than the Pfizer or Moderna vaccines, but it’s important to note that doesn’t mean lower real world effectiveness.

The J&J vaccine’s efficacy was 66% in the trial, on average, which included an efficacy of 72% in the US and 57% in South Africa. Pfizer and Moderna both had an efficacy around 95%. Each trial diagnosed COVID cases a little bit differently, so they aren’t necessarily measuring the exact same thing.

But, importantly, the Moderna and Pfizer vaccines were tested before any of the recent variants were circulating. The J&J vaccine is known to provide some protection against the South African variant, since that was the dominant strain in South Africa during the trial there, and against the Brazilian variant, which was circulating in the Brazilian arm of the trial. If the Moderna and Pfizer vaccines were tested under the same circumstances, we don’t know if they’d still keep their high efficacy rates.

Bottom line, all three are good

All three vaccines have been shown to be excellent at preventing deaths and hospitalizations. That’s the most important job of any COVID vaccine, and all three of our options are great at it. That’s why experts are saying to get whatever vaccine you can get first.

This thoughtful piece at Kaiser Health News may help you make that decision. In addition to the efficacy numbers being impossible to compare directly, the article points out that the J&J vaccine also seems to have milder side effects, and so it may be a better option for older and sicker people. And since the J&J is easier to administer, it may turn out that vaccine clinics giving the J&J vaccine are going to be more accessible to more people.

Here’s another take, an opinion piece in USA Today written by a group of doctors and scientists. They point out that all the vaccines are 100% effective in preventing death from COVID, and add: “Waiting for a more effective vaccine is actually the worst thing you can do to lower your risk of getting severely ill and dying of COVID-19.”

This article in the American Journal of Preventive Medicine does the math on that: a less-effective vaccine, given sooner, saves more lives than waiting for one with better numbers.

Bottom line, you aren’t doing yourself any favors if you turn down one vaccine to take your chances with another. The more people we can get vaccinated, the sooner we’re all protected.