close up of a COVID-19 spike

Here are 3 reasons to be excited about the Johnson & Johnson vaccine

The medical community is ecstatic about the Food and Drug Administration approval of the Johnson & Johnson vaccine, the third vaccine to be used for the prevention of COVID-19.

While COVID-19 infections and deaths are still occurring at an alarmingly high rate in the United States, we’re finally seeing a downtrend in new cases, hospitalizations and deaths. Measures such as masking, physical distancing and vaccination are making an impact.

The introduction of a third vaccine will help continue that impact.

The Vaccine Platform

The J&J vaccine is a more commonly used vaccine platform. This may help alleviate concerns of those with hesitancy over accepting newer messenger RNA (mRNA) vaccines. It uses a harmless adenovirus, or cold virus, engineered to carry the genetic code for SARS-CoV-2 spike protein, which instructs the body to produce an immune response.

This type of vaccine model also is used for the Ebola vaccine and has been found safe and well tolerated in more than 200,000 people in other vaccine studies.

New Variants

For a COVID-19 vaccine to be approved by the FDA, it must show at least 50 percent effectiveness. Pfizer and Moderna, the companies who produced the mRNA vaccines, have shown an amazing degree of efficacy — 95 percent and 94 percent, respectively. The J&J vaccine is 66 percent effective overall. Although the efficacy is less than the Pfizer and Moderna vaccines, comparing them head-to-head is like comparing apples and oranges. The various vaccine studies were performed in different parts of the world and during different time periods. The mRNA vaccines also were tested prior to the emergence of newly circulating variants.

The J&J vaccine studied 44,000 people in the United States, South America and South Africa. One of the concerning new variants is in South Africa, where it composes 95 percent of circulating virus. Even with this variant, the J&J vaccine showed 57 percent effectiveness in South Africa against milder disease.

In the United States, where the variants aren’t prevalent, the vaccine is 72 percent effective. Additionally, across all three countries, the vaccine was 85 percent effective in preventing severe COVID-19 and 100 percent protective in preventing hospitalizations and death.

One and Done

J&J is the only vaccine authorized as a single dose. We know people who’ve driven hours to receive their vaccine. Some other people who received their first vaccine also may have difficulty scheduling their second dose.

This vaccine also can be kept in a refrigerator. It doesn’t need to be frozen for stability and is therefore easier to store and transport. More places can carry it like doctor’s offices and pharmacies. This allows us to vaccinate vulnerable populations, like those with limited access to health care and people in rural areas, ensuring that everyone has an opportunity to be vaccinated regardless of their race, ethnicity, income level or insurance status. This translates to more doses into more arms and a step closer to herd immunity.

All three vaccines approved for emergency use prevent the worse outcomes of infection. All three are 100 percent effective in preventing hospitalization and death from COVID-19. Any one of the three vaccines is the best one to receive if it’s available to you.

Vaccine Smarts is written by Sealy Institute for Vaccine Sciences faculty members Drs. Megan Berman, an associate professor of internal medicine, and Richard Rupp, a professor of pediatrics at the University of Texas Medical Branch. For questions about vaccines, email