What You Need to Know About COVID-19 Vaccines

Dr. Cassandra Pierre, Boston Medical Center's acting hospital epidemiologist, spoke with members of the Federal Home Loan Bank of Dallas (FHLB Dallas) in a members-only webinar recently to provide expert insight into the COVID-19 vaccines and to answer members’ questions.

Dr. Pierre is an infectious diseases physician and one of Boston Medical Center’s go-to experts on COVID-19 and vaccinations. She is also an assistant professor of medicine at Boston University School of Medicine.

Dr. Pierre explained how the various vaccines work and answered a wide range of questions about them.

The Pfizer and Moderna COVID-19 vaccines, which are currently available in the United States under the U.S. Food and Drug Administration (FDA) emergency use authorization, work by targeting a specific spike protein that sits on the surface of the virus that causes COVID-19, she said.

“If you are exposed again to a spike protein with a real infection, your body knows what to do. It snaps into an attack mode and you are able to prevent yourself from becoming infected (with COVID-19),” Dr. Pierre said. “The spike protein that your body is producing during the vaccine process is not infectious and will not make a person sick.”

There are other strategies with other potential vaccines still under development. Those include vaccines from Johnson & Johnson, AstraZeneca and Novavax.

Of the two now available in the United States, both have reported 95 percent efficacy. Two doses are necessary for both and are spread out over several weeks. Johnson & Johnson is the only vaccine for COVID-19 that is pursuing a one-dose strategy.

Distribution Challenges

The Pfizer vaccine must be kept at extremely cold temperatures which mostly requires it to be used in hospital settings and urban locations with access to ultracold storage, Dr. Pierre said. Moderna doesn’t have to be as cold so it is more versatile on where and when it can be stored and distributed. Other vaccines still in development have even more versatility on storage temperatures, she said.

Vaccine Side Effects

The vaccines are safe, but some concerns have arisen for people with severe allergies who have anaphylactic responses due to those allergies. So far, those responses related to the vaccines have been rare, and there have been no deaths from anaphylactic responses for people getting the vaccine, Dr. Pierre said.

You Got the Vaccine, What Now?

If you’ve received two doses of the vaccine, you won’t instantaneously have protection. 

“About two weeks after your second dose is when we expect you to have the optimal response of efficacy,” she said.

Even those who have had COVID-19 should get vaccinated as their immunity seems to wane over time, and the vaccine will prolong immunity, Dr. Pierre said.

The world will begin to reopen for those who receive the vaccine in ways that it wasn’t before, Dr. Pierre said.

“You can do things after these vaccines that you couldn’t otherwise do before,” she said. “For example, you can plan your vacations again. You can also have a sense of safety and security knowing you have done everything you can to protect yourself, your family and protect the community.”

Vaccinated work colleagues may be able to gather unlike colleagues who haven’t been vaccinated, she added. In fact, some corporate executives have already started promoting the vaccines and are encouraging employees to get them, according to a January 25 article in The Wall Street Journal, which quotes several executives on what they are doing to encourage vaccinations.

Once such company is VMware. VMware CEO Patrick Gelsinger, who is leaving the company in a few weeks to become chief executive of Intel Corp., said in the article that VMware is considering bringing in medical professionals to answer employee questions about the vaccine during virtual all-hands meetings, according to the WSJ article. “Taking those who are maybe concerned and helping to remove doubt: I think that’s an important piece of what businesses can do,” he said.

In the webinar, Dr. Pierre said the faster the vaccine can get distributed the better it will be for addressing mutations already circulating around the globe. Moderna, in fact, just announced it is looking into boosters to protect against variants of the coronavirus.

“The longer we have widespread transmission in the community, the more chances and opportunities for a variant to arise that will change the spike protein just enough that the vaccines will only offer partial immunity, lower immunity or even no immunity,” she said.