The COVID-19 vaccine holds promise for bringing an end to the pandemic. But some have questioned the rapid development of the vaccine — so I talked with some scientists about how pharmaceutical companies were able to work so quickly.
Michael Olson is an assistant professor of immunology with SIU School of Medicine. He saidthe first thing to understand how the body develops an immune response.
“So your body is trained to recognize things that are not self, so something that's foreign,” Olson said. “And so anytime a foreign thing is recognized, your body goes through a process of presenting that foreign thing to various immune cells. And then those immune cells try to make an antibody response. That's all part of what is called adaptive immunity.”
A vaccine trains the body to respond to a specific foreign infection — in this case, the novel coronavirus
“What takes place is that your body needs to be trained to recognize something foreign. And so the vaccine provides that more material to train your body to have antibodies, essentially, to do that thing, And in doing so, thing, when your body is exposed to that challenge is what we would call it is able to have a much faster response because you already have the antibodies in your system and ready to go,” said Olson.
Vaccine development isn’t a new field — the very first smallpox vaccine was created in 1798. But it still may take ten years or more to create a vaccine for a new disease, in many cases.
The COVID vaccine went faster, in part because of the number of scientists working on finding a way to prevent COVID and the amount of money provided by governments and pharmaceutical companies. The vaccine trials were held at hundreds of sites around the world, far more than scientific trials usually have, which let scientists get the data they needed quickly.
The fact that the pandemic is so widespread also helped, Olson said.
“A lot of times in those, you have a very specific patient population that you're looking at. Right? So somebody who's at risk for this, or has had this in the past and the chance for it to develop,” Olson said.
In addition to having a wider pool of patients, researchers could also be confident that a percentage of subjects enrolled in trials were potentially exposed to COVID-19. That means they could tell if the vaccine worked in a short time frame.
“One thing that people don't think about, really, that to show that a vaccine works, you have to have a challenge,” Olson said. “And with the disease burden as high as it is in the United States than the likelihood of people getting the infection in the placebo group was high, you didn't have to wait for years to find out if people were protected, right, you're able to find out over the course of two months that the numbers were drastically reduced in the vaccine group compared to the placebo.”
And while it may not seem like anyone had much luck in 2020, one lucky break for scientists was the timing of RNA vaccine development.The first two COVID vaccines, made by Pfizer and Moderna, use mRNA to prompt the body’s immune response. While the novel coronavirus is also an RNA virus, those two things aren’t actually related, according to Keith Gagnon, assistant professor of biochemistry at SIU.
“It's sort of a scientific coincidence that we have an RNA virus, and it's being treated with an RNA based vaccine,” Gagnon explained.
Gagnon’s research focuses on RNA, and he’s been following the development of RNA vaccines for a while.
“The timing for the technology, I would say, was very good time. RNA as a vaccine, this ideas been around for a long time,” Gagnon said. “The group who's working with Pfizer, Biontech, has been developing this for a while. And, in fact, it's been in testing and clinical trials and preclinical work, which means, trying to get to the point where it can actually be used for people safely. It's been in that state for a couple years.”
Messenger RNA, which is used in the Pfizer and Moderna vaccines, works essentially as a translator, relaying the instructions from DNA to tell the body to create proteins.
“The mRNA is pretty unstable, it gets turned over or degraded by the cell really quickly. So it just lasts long enough to make this protein,.It's not like DNA, which could possibly get incorporated into the person's genome, or they can stick around for a long time,” Gagnon said.
Scientists can control how long the RNA lasts in the body, and what proteins it produces. In the case of COVID, the vaccine focuses on one specific, identifiable protein made by the virus.
“It creates almost a wanted post just for the body. Because, you know, you don't need to know what that person looks like in 3D, or what clothes they wear, you just need to know what their face looks like. So you just need to make one protein for the virus. And it's like a snapshot of the virus and that's enough for it to know, who to look for and where to go,” Gagnon explained.
There are drawbacks to mRNA, including the fact that it can be less stable than other types of vaccines. That’s why the Pfizer and Moderna vaccine have to be stored at such cold temperatures and have shorter shelf lives.
In the meantime, Olson knows that understanding these new vaccines and sorting through false claims can be confusing. He said there’s one thing he would want everyone to understand.
“There is no possible way from this vaccine to get COVID or pass it on to anybody else,” Olson said. “You are receiving a tiny subset of one protein within the virus. No virus is there that can be transmitted through the taking of the COVID-19 vaccine.”