Questions About COVID Vaccines? Two Scientists Explain.
The COVID-19 vaccines hold promise for ending the pandemic, and millions of Americans have received at least one shot. But 39% aren’t likely to get a vaccine, according to a December study from the Pew Research Center. One of the main reasons: a lack of trust in the research and development process.
Side Effects asked two scientists at Southern Illinois University’s School of Medicine about those reservations.
Michael Olson, an assistant professor of immunology, says COVID vaccines work like others — and the first thing to understand is how the body develops an immune response.
“So anytime a foreign thing is recognized, your body goes through a process of presenting that foreign thing to various immune cells," he says. "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 invader — in this case, the novel coronavirus.
“What takes place is that your body needs to be trained to recognize something foreign," he says. "And so the vaccine provides that more material to train your body to have antibodies, essentially, to that thing."
Vaccine development isn’t a new field — the first smallpox vaccine was created in 1798. But it still may take 10 years or more to create a vaccine for a new disease.
The COVID vaccine went faster, in part because of the huge amount of money provided by governments and drug companies. Vaccine trials were held at hundreds of sites around the world. And with so many people exposed to the virus, Olson says scientists could quickly see the difference between subjects who were vaccinated and those who weren’t.
“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,” he says. “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, scientists got a break in perfecting a certain type of vaccine. It uses a process called messenger RNA — or mRNA — to trigger the body’s immune response at the cellular level.
Keith Gagnon, an assistant professor of biochemistry, says mRNA works as a translator, telling the body what to do. In the case of COVID, the vaccine focuses on one specific protein made by the virus.
“It creates almost a wanted poster for the body. 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 says.
The first two vaccines, made by Pfizer and Moderna, use mRNA. But there are some drawbacks — they have to be stored at very cold temperatures and have a shorter shelf life.
“But 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,” Gagnon says, explaining that the RNA used does not stay in the body.
Olson knows that understanding these new vaccines and sorting through false claims can be confusing. He says 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, 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,” Olson said.
This story was produced by Side Effects Public Media, a news collaborative covering public health.