By Jonny Lupsha, Wondrium Staff Writer
Two-dose COVID-19 vaccines may not be necessary for people who have been infected by the novel coronavirus or survived COVID-19 illness. This is because once someone has been infected, their immune system should recognize it when it’s reintroduced to their bodies. So, is just one dose recommended?
When a person gets a virus for the first time, their immune system locates and recognizes it as a foreign entity. It takes some time for the immune system to learn how to neutralize it before ejecting it from the body. However, when that same virus is reintroduced to the body in subsequent infections, the immune system has a far easier time recognizing and fighting it. This fact may make millions of doses of the COIVD-19 vaccine additionally available for use by people who have not been infected by the virus.
Both Pfizer’s and Moderna’s vaccines against the novel coronavirus require two shots, given several weeks apart. The first dose teaches the body what the coronavirus is like and how to recognize it. The second dose puts the immune system to the test. However, a growing number of health experts are saying that if a COVID-19 survivor gets the vaccine, their body should already recognize it, doing the first shot’s job. This means their first shot would be like the equivalent of the second shot in someone who had never been infected by the virus, and a subsequent shot would be unnecessary.
Of course, the recently approved Johnson & Johnson vaccine against COVID-19 only requires one dose, anyway; so it doesn’t apply to this recent development. Researchers say people who have been infected by the novel coronavirus and COVID-19 survivors should still get Johnson & Johnson’s single-dose vaccine, if possible.
How do initial and subsequent exposures to illnesses—or vaccinations—work? In his video series Medical Myths, Lies, and Half-Truths: What We Think We Know May Be Hurting Us, Dr. Steven Novella, Assistant Professor of Neurology at the Yale School of Medicine, broke down how and why vaccinations work.
Once Bitten, Twice Shy
“A primary immune response—that’s what we call a response to something that your immune system is encountering for the first time—and that primary immune response peaks at about five to 10 days,” Dr. Novella said. “That’s a long time for a virus or for a bacteria to be reproducing itself and spreading throughout your body. A subsequent immune response—the second, third, or fourth time that you are being exposed to a germ, a virus, or a bacteria—your immune system’s response will peak in only one to three days.
“That’s a lot faster, and that means it can fight off that infection much, much earlier and much more robustly.”
Additionally, according to Dr. Novella, during a subsequent exposure to an infection, the number of antibodies your body produces is far greater than on its first encounter, and they persist for a longer period of time in the body than they do with the initial infection.
How Antibodies Help
The reason this matters for COVID-19 vaccinations is huge. When a person who never contracted the novel coronavirus gets both doses of the vaccine, then even if they do contract the virus at a later date, their immune system will be primed and ready—and with a huge amount of antibodies on the way—to fight COVID-19.
“Antibodies are one of the primary components of the immune system,” Dr. Novella said. “They are proteins that will bind to foreign substances and target the other components of your immune system against those invaders; so antibodies are essential.”
Preparing the body against infection is one of the most important functions of a vaccination. If we can understand how vaccines work and disregard medical misinformation associated with them, lives can be saved.