Coronavirus vaccine booster shots may be necessary to fight future variants, Rutgers experts say

Individuals who have received the coronavirus disease (COVID-19) vaccine may potentially need booster shots after 12 months as well as annual vaccinations to maintain immunity and to protect against variant strains, according to Rutgers experts.

Reynold Panettieri, vice chancellor for translational medicine and science at the University, said the overall effectiveness of the vaccine will likely decline over time, as it does with most others.

“The long-term efficacy of the vaccine to generate immunity will wane since such immunity fades with almost every vaccine,” he said.

One such instance is with the tetanus vaccine, said Stanley H. Weiss, epidemiologist and professor at the Rutgers New Jersey Medical School and the School of Public Health. The Centers for Disease Control and Prevention recommends that adults receive a tetanus booster shot every 10 years to maintain protection.

The COVID-19 vaccine provides immune protection through antibodies and cellular immunity, which is partly due to memory T cells, he said. The protection of each will decline over time, but since the vaccines are so new, it is unknown how long the immune response will last. 

Weiss said that since variations exist in people’s responses to the vaccine, boosters may be needed in order to maintain maximum immunity. Booster shots may also be needed to protect against COVID-19 variants.

“Virus variants are arising that are less susceptible to the immune response to the vaccines developed on the original (wild type) virus,” Weiss said.

Two weeks after the second dose of the Pfizer and Moderna vaccines are administered, immune protection seems to extend to the most common variants in the region. New variants are expected to arise from other regions of the world, which may not be covered by the existing vaccines, Weiss said.

Panettieri said that some common diseases which also require vaccine booster shots are the influenza, hepatitis B and Streptococcus pneumoniae, which is responsible for most cases of community-acquired pneumonia.

The reason that certain vaccines only require one dose while others require several doses is due to the varying mechanisms of action in different types of vaccines, he said. For instance, the mRNA vaccine that is offered by Pfizer and Moderna requires two doses to generate maximal immune protection, while Johnson & Johnson’s viral vector vaccine only requires one dose.

Panettieri said that even though the development of the COVID-19 vaccines occurred at an extraordinary speed, the testing and development process did not cut corners, and the potential need for booster shots is unrelated.

As of now, it is unknown whether the COVID-19 booster shot will be identical to the initial vaccine dose, and it could be from six months to even years before one is needed depending on the individual, he said. Future research hopes to find out when people will need to receive the booster, if at all.

If a booster shot is needed, people should expect extended and expanded protection against COVID-19, Weiss said.

“The studies are ongoing, but this question is critically important and must be addressed,” Panettieri said.