Experts say one-shot COVID vaccine is safe, effective

Johnson & Johnson’s COVID-19 vaccine may not have as high of an overall efficacy rate as vaccines produced by Pfizer-BioNTech and Moderna, but comparing Johnson & Johnson to the other two is a bit misleading, health practitioners say.
Johnson & Johnson’s one-shot vaccine has a 66% efficacy rate, compared to 95% for Moderna’s and Pfizer-BioNTech’s two-shot vaccines, Dr. Tracy Lemelle said. Lemelle, a medical director at Blue Cross & Blue Shield of Louisiana, said each vaccine had different trials, was done at different geographic areas and was conducted at different time periods.
Testing for the Moderna and Pfizer-BioNTech vaccines was done early in the pandemic, while Johnson & Johnson was done later. Also, trials for the Pfizer-BioNTech and Moderna vaccines only were conducted in the United States, Lemelle said.
State Health Officer Dr. Joe Kanter said in a webinar Thursday that Johnson & Johnson has had the largest vaccine trial, and it covered the largest area.
“It covered not just patients in the U.S., but in South Africa and in Latin America as well,” he said.
At the time of the Johnson & Johnson trials, Lemelle said South America, one of the areas the trials were taking place, had “more contagious variants” present.
“When Moderna and Pfizer were tested, there were no variants out there that we were aware of,” Lemelle said. “By the time Johnson & Johnson came to the mix, there was much more rampant COVID disease in general, and there were multiple variants.”
Therefore, she said, Johnson & Johnson’s 66% efficacy factors in all of the trials in the various locations.
“Now, if you look at their efficacy as it relates to just the United States, they are much more in line with the numbers that we see from Moderna and Pfizer,” Lemelle said.
As for the technology used in the vaccines, Pfizer-BioNTech and Moderna use mRNA.
The mRNA brings “bits of genetic code” to the body’s cells, Lemelle said.
“This code gives your cells an instruction sheet, basically, and tells your cells how to make a harmless piece of the spike protein that is on the outside of the coronavirus,” she said.
The mRNA is comparable to the social media platform SnapChat in that the message is received, read and then disappears, Baton Rouge cardiac anesthesiologist Dr. Max Madhere said on a Blue Cross Blue Shield webinar Wednesday.
After receiving the vaccine, the body’s immune system can identify the protein and fights off the virus if it is exposed, Lemelle said.
Madhere likened the vaccine to practicing for a sports contest.
“The vaccine delivery system is basically like practice for when you actually get in the game, or in our sense, sees the real thing, we’re ready to fight it,” he said.
Madhere said the mRNA does not interact with the body’s DNA.
The Johnson & Johnson vaccine is more like the vaccines consumers are used to in that a dead virus from which the common cold comes from is used. It’s like what is used in the flu vaccine, Lemelle said.
“They take that virus, they modify it so that it is harmless,” Lemelle said.
She said the “genetic blueprint for the spike protein” is delivered in this dead virus.
Then, the body’s immune system recognizes it.
“So similar ideas, just different ways of doing it,” Lemelle said.
Lemelle said COVID-19 cannot be contracted through any of the vaccines, even Johnson & Johnson.
“It’s a dead virus,” she said. “It’s not possible to get COVID from the vaccine.”
Regardless of the vaccine consumers receive, Lemelle said each is 100% effective at protecting consumers from death from COVID-19, and they are almost full-proof at helping the public avoid “severe hospitalization.”