COVID vaccines give us much better protection than a COVID infection, say infectious disease experts.

That’s one of many reasons to get a COVID shot, which are rigorously (and continually) tested for safety. The vaccines trigger a significantly more robust immune response than a naturally-acquired infection. Ultimately, this better prepares your body for a real infection, which can ravage the lungs, among other risks.

“I would advise everyone to get the vaccine,” said Philip Felgner, an infectious disease expert and director of the Vaccine Research and Development Center at the University of California, Irvine.

“I would advise everyone to get the vaccine.”

The evidence is strong. For example, Felgner and other researchers assessed thousands of blood samples from people who were naturally infected with the coronavirus, versus those who received an FDA-authorized mRNA vaccine (Pfizer and Moderna). The new research, published online and now currently under peer-review, found the immune system’s response is “much stronger” with vaccines, explained Felgner. Following the second shot, people had ten times more antibodies than people who recovered from COVID.

The CDC agrees that vaccines are superior. The agency notes the likelihood of reinfection after a natural infection “may increase over time” after a few months, and the vaccines provide the best protection against COVID illness, which can be serious. “The risk of severe illness and death from COVID-19 far outweighs any benefits of natural immunity,” the CDC writes.

Some prominent national politicians continue to claim they don’t need vaccination after getting infected by the coronavirus. Yet COVID vaccines produce better immunity than a naturally-acquired infection for a number of reasons:

  • Better spike: The FDA-authorized vaccines don’t contain the coronavirus, just genetic instructions (like computer code) for our cells to create just a piece of the virus — specifically the spike protein that lets the virus enter and infect our cells. By seeing just this foreign, spiky intruder, our immune system can then make defenses to block the spike from attaching to our cells. Crucially, the vaccines provide our immune system with a much better “view” of the spike than an infection can, because the virus has evolved to conceal some portions of its spike proteins. This means with a natural infection our immune systems don’t create as effective of defenses against the coronavirus’ spike. “The virus is clever,” explained Dr. Peter Gulick, a D.O. and professor of medicine at Michigan State University. By hiding part of the spike, the body can’t react as well to the virus, Dr. Gulick said.

  • No immune interference: Unlike vaccines, a coronavirus can attack or interfere with our immune system. This likely adds to a weaker immune response during an infection, because the virus can do things like attack our immune cells, explained Dr. Wesley Long, an M.D. and infectious disease expert at Houston Methodist, an academic medical center in Texas. But there’s no “pathogenic trickery” with COVID vaccines: “There’s none of the other viral activity going on that otherwise interferes with the immune response,” explained Dr. Long. Ultimately, this leaves our immune system better equipped to identify and deal with a future exposure or infection.

  • Effective dose: How much coronavirus someone is exposed to likely matters, explained Felgner, of UC Irvine. But with natural infections, one’s exposure can vary significantly, meaning too low a “dose” could result in a weaker immune response. This might be why some people who were infected with the coronavirus don’t end up having detectable levels of protective antibodies, Felgner explained. Consequently, these people remain vulnerable to infection. “They would presume to be susceptible,” he said. In sharp contrast with variable infections, everyone vaccinated receives a standardized dose of the vaccines, an amount researchers tested to ensure a robust immune response.

A graphic of the spike protein that binds to our cells and causes COVID-19.

A graphic of the spike protein that binds to our cells and causes COVID-19.

Image: Sikora M / PLoS Comput Biol, 2021

The benefits of vaccination are unambiguous. “The evidence is really clear,” said Dr. Long, noting vaccines have driven sharp declines in infections, hospitalizations, and death. “The vaccines do provide better immunity.”

What’s more, infections also come with the drudgery and serious risk of, well, infections. The effects of resulting illnesses don’t always vanish. “There may be longer-term consequences,” said Dr. Gulick. The CDC has found some people can experience “long-haul symptoms” weeks to months after an infection, including shortness of breath, brain fog, fatigue, and beyond. 

SEE ALSO: 5 big COVID vaccine myths, debunked

Experts who best understand how viruses and vaccines work are choosing vaccines to ensure superior immunity.  

“I wouldn’t trust an infection at all,” said Felgner.