All your COVID-19 vaccine questions answered

In anticipation of pivotal vaccine decisions that will be made by the Food and Drug Administration this week, Northeastern faculty from the Bouvé College of Health Sciences discussed the most pressing vaccine questions during a Facebook Live panel on Wednesday. Screenshot by Northeastern University

When can I get a vaccine? How does it work? And will I still need to wear a mask afterward? 

These are some of the many questions people have in advance of the Food and Drug Administration’s open committee meeting on Thursday, when the agency is expected to make the final decisions regarding approval of a COVID-19 vaccine for emergency use authorization in the United States. 

In anticipation of this pivotal step in ending the pandemic, Northeastern faculty from the Bouvé College of Health Sciences discussed many of these pressing vaccine questions during a Facebook Live panel on Wednesday. 

The conversation, moderated by Gene Tunik, the associate dean of research and innovation at Northeastern, began with an explanation of what the vaccine actually is. 

What is an mRNA vaccine?

Both of the top vaccine candidates, produced by pharmaceutical companies Pfizer and Moderna, are messenger RNA, or mRNA, vaccines. They create immunity by enabling cells to produce proteins that mimic parts of the SARS-CoV-2 molecule, triggering the immune response without introducing the virus.  

“They’re made from synthetic mRNA, which is based on the genetic code from the viral molecule,” explained Mansoor Amiji, university distinguished professor of pharmaceutical sciences and chemical engineering. 

This type of vaccine has never been approved by the FDA. But even before the pandemic, pharmaceutical companies were experimenting with mRNA vaccines, which partially explains how the vaccine could be produced so quickly. 

Amiji uses a baking analogy to explain the expedited process: Blueberry muffins and chocolate muffins have different ingredients, but they use the same recipe. “These mRNA vaccines have been developed relatively quickly because the recipe was already there.” 

How was it tested?

Both vaccines under review in the U.S. have completed Phase III trials, the last stage before a product reaches the general population. Once the vaccines are more widely available, these pharmaceutical companies will continue with Phase IV trials that monitor the effects of the vaccine in the general population, Amiji said. 

During animal trials, the vaccines displayed robust immune responses. “One thing you can do in animal trials that you can’t do in human trials is expose test subjects to the virus” to test efficacy, Amiji says. 

When will the vaccine be available?

Pfizer, whose vaccine will be reviewed by the FDA on Thursday for emergency use authorization, has already manufactured a limited number of doses and is waiting for the administration’s green light to distribute them, explained Brandon Dionne, an assistant clinical professor in the School of Pharmacy.

The key word here, though, is limited. In the U.S., healthcare workers and elderly people living in long-term care homes will receive the vaccine first. “For most people, it’s going to be sometime next year before they get access to a vaccine,” Dionne said. 

How effective are the COVID-19 vaccines?

The two leading vaccine candidates are both close to 95 percent effective at preventing symptomatic COVID-19, as well as preventing severe cases of the disease, Dionne said. 

But it’s possible that people who receive the vaccine can still be asymptomatic carriers.

“It will likely reduce transmission. We just don’t know to what extent,” he said. The other question scientists still need to answer is how long immunity from the vaccine will last and whether booster shots will be necessary. 

Which vaccine should I get?

“It doesn’t matter which vaccine people get because they’re both very effective,” Dionne said. “But they’re both going to be limited, so you should get whichever one you have access to.” 

Both vaccines are a two-dose series, and the second dose needs to be the same brand as the first, he said. Pfizer’s doses will be administered 21 days apart, and Moderna’s will be 28 days apart. 

Is the COVID-19 vaccine safe? What if I have a pre-existing condition?

The Centers for Disease Control and Prevention’s advisory committee will provide guidelines for the general population, including people who are at risk for severe cases of COVID-19, on whether the vaccines are safe for people with certain conditions, Dionne said. 

While it’s still too early to say definitively, Dionne suspects that the vaccines will be safe for people with comorbidities. 

The mRNA vaccine creates immunity by using your body’s cellular machinery to make spike proteins—molecules that mimic the crown-like spears on the surface of the virus. Then your immune system creates antibodies to the spikes, Dionne explained. 

In other vaccines, such as the Lyme disease vaccine, there have been concerns that the proteins used to create immunity are too similar to proteins already found in the body, causing joint inflammation, Dionne said. 

“We don’t have that same concern for the spike protein in the COVID-19 vaccine,” he explained. “The likelihood of significant adverse effects further down the road are much lower,” even among those with comorbidities. 

Pending further review by the CDC, people with comorbidities are expected to be next in line for the vaccine after healthcare workers and the elderly. 

Do we still need to wear masks and distance ourselves after the vaccine is distributed?

Yes, you still need to wear a mask, keep your distance, and follow safety practices despite the introduction of a vaccine, said Neil Maniar, professor of the practice and director of the Master of Public Health Program.

“There’s a lot of excitement about the vaccine. It’s a light at the end of a very long and difficult tunnel,” he said. “But it’s important to maintain those best practices to protect those who are not yet vaccinated.” 

How many people are willing to get vaccinated? And why are some hesitant?

“The latest polls say 60 percent of people are likely to get the vaccine, which is an increase from earlier this year,” said Laura Dudley, an associate clinical professor and director of the Applied Behavior Analysis Program

But some people aren’t concerned about getting sick, so they don’t want to go through the trouble of getting the vaccine. Others fear the vaccine will be unsafe because the vaccine production process was so quick. Concerns about safety also tap into pre-existing distrust of the medical system, especially among minority populations, Dudley said. 

“There’s a history of racism within the medical system where great harm has been committed in the name of science and advancing medicine,” she said. 

Her advice for broaching the subject with those who are skeptical of the vaccine: Don’t try to convince them they’re wrong. Try to understand their point of view, and your conversation will be much more productive. 

What does the future of the vaccine look like beyond the United States?

“We have to remember that when we talk about a pandemic, we’re talking about something that’s global,” said Alessandro Vespignani, the Sternberg Family Distinguished University Professor of physics, computer science, and health sciences. 

He recommended that wealthy countries use their resources to help distribute the vaccine in developing countries where a lack of infrastructure could pose serious logistical threats for the finicky vaccines, some of which need to be stored at extremely low temperatures.

“The vaccine will be a game-changer in the U.S. and the U.K. and Canada, who approved it recently. Europe will follow soon, but we can’t defeat the pandemic unless we take into account other countries,” he said. 

“We need to be generous and not selfish. We need to think about not just us but humankind.” 

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