To receive a COVID-19 vaccine or not — for some, this is the major question of the first half of 2021.

As new versions of the coronavirus vaccine roll out in the United States, some people are eager to receive one, while others are hesitant. Earlier this week, the Centers for Disease Control and Prevention released new guidance on safe behaviors for people who have been vaccinated, such as spending time indoors with other vaccinated people without wearing masks or maintaining physical distance.

Health professionals, including the New River Health District, say that all three coronavirus vaccines  — Pfizer, Moderna, and Johnson & Johnson — are effective in preventing serious illness, hospitalization, and death as a result of COVID-19.

Two Virginia Tech experts on public health and vaccine efficacy provide answers to common questions about the safety, timing, and testing process of the coronavirus vaccine.


Read more from Laura Hungerford, a professor who heads the Department of Population Health Sciences, and Kate Langwig, an infectious disease ecologist and assistant professor in the Department of Biological Sciences.

Q. The coronavirus vaccine was created and approved at an unprecedented rate. How can we have confidence in the testing process?

Langwig: One of the reasons we were able to create the vaccines so fast was that scientists had been previously developing vaccines for SARS [Severe Acute Respiratory Syndrome] and MERS [Middle East Respiratory Syndrome], which are also both caused by coronaviruses. Those diseases were never as widespread as this one, so there wasn't as much momentum to bring those vaccines online rapidly. 

Obviously for SARS-CoV-2, there was a greater availability of resources to develop and test the vaccines. Another key point is that Phase III vaccine trials, which are the ones that usually measure the efficacy of a vaccine (not just whether it causes side effects) rely on participants becoming infected in the control group of the study. Because SARS-CoV-2 is so prevalent, the studies reached the number of cases in the control group needed to assess vaccine efficacy very quickly. Importantly though, no steps were skipped.

Kate Langwig is an infectious disease ecologist and an assistant professor in the Department of Biological Sciences at Virginia Tech. Photo by Ryan Young.
Kate Langwig is an infectious disease ecologist and assistant professor in the Department of Biological Sciences. Photo by Ryan Young.

Q. Some people say they want to wait a little longer before they get a COVID-19 vaccine in order to see how others react to the initial rounds of vaccinations. Should people wait?

Hungerford: Fortunately, people have been being vaccinated since December. So, for those who wanted to wait a bit, the waiting can be over since millions of people have already been vaccinated, adding to evidence that the vaccine is safe and effective. We know the side-effects of the vaccine are much less serious than getting sick with COVID-19. And longer term, doctors are beginning to see other conditions arising after recovering from COVID-19, even in those who had mild cases. So, there are serious risks to waiting and not getting the vaccine, while we don't have evidence of matching risks due to the vaccine. Plus, the CDC's newest guidance says that starting two weeks after you're completely vaccinated, you can relax some of the masking and social distancing practices in some situations.

Langwig: I encourage everyone to get the vaccine as soon as they are eligible. For this virus, every person infected can infect two to three other people, on average. We now have new variants of the virus that have emerged that are even more transmissible. In order to prevent against the spread of these new variants, we need every person to be vaccinated as soon as possible. This will reduce the number of people available for each person to infect and also reduce the population size of the virus to prevent new variants from taking hold. 

Laura Hungerford is a professor and head of the Department of Population Health Sciences at the Virginia-Maryland College of Veterinary Medicine. Photo courtesy of  Hungerford.
Laura Hungerford is a professor and head of the Department of Population Health Sciences at the Virginia-Maryland College of Veterinary Medicine. Photo courtesy of Hungerford.

Q. Should people wait to get a vaccine until it is tested against all the new strands of COVID-19 that are popping up?

Langwig: No. Vaccination is typically not an all-or-nothing process; people who have been vaccinated are usually partially immune against similar pathogen variants. For example, a vaccine might be 90 percent effective against the strain it was designed to protect against while being 70 percent effective against a similar, but not identical, strain. As a result, it is better to get the vaccines available now and protect as many people as we can. We can always get vaccine boosters later.

Q. If I had COVID-19 and have antibodies, why should I get the vaccine?

Hungerford: There seems to be really good news if you get the vaccine and you've already had COVID-19. Your immune response is better than those who just get COVID-19 or just get a vaccine. Although you may have immunity due to COVID-19, we don't know how long it lasts. So, the vaccine seems to give you better and longer lasting protection.

Q. What do we know about how the coronavirus vaccine interacts with health conditions like heart disease and diabetes?

Hungerford: The vaccine causes your body to mount an immune response to a part of the virus without ever seeing the real virus. Since those with heart disease, diabetes, etc., are the most fragile when attacked by the virus, they actually benefit the most from protection of the vaccine. That is why those with these underlying conditions are being vaccinated before others in the general population.

Q. How does the vaccine impact pregnancy and/or nursing mothers and the ability for someone to become pregnant in the future?

Hungerford: Currently, the CDC [Centers for Disease Control] and groups that make recommendations for pregnant women, such as the American College of Obstetricians and Gynecologists, have been supportive of vaccines for pregnant persons, especially if they have factors that increase disease risk. This is because COVID-19 can have consequences if the mother becomes very ill, such as the mother's death or pre-term delivery. But pregnant women were not included in the vaccine trials. So, pregnant women should consult with their doctors to determine their level of risk and determine the best plan.  

By Travis Williams and Jenny Kincaid Boone

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