As progress continues in developing coronavirus vaccines to fight the COVID-19 pandemic, a third vaccine has been authorized for use. On Feb. 27, 2021, the U.S. Food and Drug Administration (FDA) gave an emergency use authorization (EUA) for a Johnson & Johnson COVID-19 vaccine for people age 18 and older.
Lisa Maragakis, M.D., M.P.H., senior director of infection prevention, and Gabor Kelen, M.D., director of the Johns Hopkins Office of Critical Event Preparedness and Response, answer your questions about the newest COVID-19 vaccine.
Does Johns Hopkins Medicine recommend the Johnson & Johnson vaccine?
Yes, we do. We view all three available COVID-19 vaccines as highly efficacious for preventing serious disease, hospitalization and death from COVID-19. The Johnson & Johnson vaccine has some advantages, including:
- The vaccine requires only one shot. This means earlier protection than other currently available vaccines. It also means not having to deal with possible side effects that could be associated with the second dose of the other vaccines.
- The Johnson & Johnson vaccine reported extremely high efficacy in preventing hospitalizations and deaths 28 days after vaccination.
- In clinical studies, the Johnson & Johnson vaccine was efficacious against the U.K. and South African COVID-19 variants. These variants were not circulating widely at the time of the clinical trials for the other vaccines.
- The Johnson & Johnson vaccine seems to reduce asymptomatic infections, which can spread the virus to others.
We, along with the Centers for Disease Control and Prevention (CDC), encourage those interested in getting vaccinated to take whichever vaccine is made available from any legitimate and authorized organization.
Does Johns Hopkins consider the Johnson & Johnson vaccine any less effective than the Pfizer and Moderna vaccines?
No, all three of these vaccines are highly efficacious at preventing the most important COVID-19 outcomes, including severe infection, hospitalization and death. For this reason, Johns Hopkins Medicine considers them to be equally efficacious. The reported efficacy of each vaccine cannot be compared directly to the others because the study design and conditions were different across the trials. For instance, the Johnson & Johnson vaccine was tested in environments with variants, such as the South African strain. The Pfizer and Moderna vaccines were not. We encourage anyone who wants to be vaccinated to pursue any legitimate and authorized opportunities, and to take whichever vaccine is available to them.
Will I have the chance to choose which type of vaccination I receive, the Johnson & Johnson, Pfizer or Moderna vaccine?
No, you are not likely to have a choice of which vaccine you receive. Vaccine allocation and distribution is determined by the federal, state and local public health authorities. Vaccination sites often have little or no advance notice regarding which type of vaccine they will be able to offer on any given day. We encourage anyone who wants to be vaccinated to pursue any legitimate and authorized opportunities, and to take whichever vaccine is offered to them.
Has Johns Hopkins Medicine received the Johnson & Johnson vaccine?
We received our first limited supply of Johnson & Johnson vaccine the week of March first. We have been advised that we are likely to receive further doses in the third week in March.
Does the Johnson & Johnson vaccine work on coronavirus variants?
In clinical studies, the Johnson & Johnson vaccine was efficacious against the U.K. and South African COVID-19 variants. These variants were not circulating widely at the time of the clinical trials for the other vaccines.
What is a viral vector vaccine, and how does it work on the coronavirus?
The Johnson & Johnson vaccine is a viral vector vaccine. This is another difference between this shot and the Pfizer and Moderna vaccines, which use messenger RNA (mRNA) technology.
Viral vector vaccines take a harmless virus, known as a vector, — which cannot cause disease or replicate — and load it with information that informs cells how to manufacture a look-alike, harmless part of the coronavirus. That part, the spike protein, cannot infect a person or cause COVID-19 illness by itself.
Once a person gets the shot, their cells receive the “directions” from the vector, telling them how to create copies of the spike protein. The cells then go to work and make them. As the spike proteins accumulate in the body, the immune system is alerted to their presence and creates antibodies and an immune reaction to fight them. After about four weeks, there is enough protection to fight off the coronavirus that has the spike protein, and prevent severe illness.
Viral vector vaccines have been created and used against infections since the 1970s. They have also been used in gene therapy to treat cancer. In addition, they have been used in studies for HIV and influenza. Some of the vaccines developed to fight the Ebola virus used this technology.