Is the Johnson & Johnson COVID-19 vaccine less safe?

(Tiếng Việt)

Claim: Many Vietnamese-Americans believe that the Johnson & Johnson vaccine is not as safe as the Moderna and Pfizer vaccines because it only requires one shot and has a lower efficacy level.

Rating: This claim is FALSE. The Johnson & Johnson vaccine has been approved by the U.S. Food and Drug Administration (FDA). It is 85% effective in preventing COVID-19 hospitalizations and 100% effective in preventing COVID-19-related deaths, according to a number of health experts including Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases.

According to the U.S. Food and Drug Administration (FDA), the Johnson & Johnson vaccine, also called the Janssen vaccine, is 67% effective in preventing moderate to severe COVID-19 infections occurring at least 14 days after vaccination. But most crucially, for severe COVID-19 infections (infections that require hospitalization), the vaccine was 77% effective 14 days after vaccination, and a whopping 85% effective 28 days after vaccination. It is also 100% effective at preventing COVID-related deaths.

And in the clinical trials of 43,783 people for safety data evaluation, no one who got COVID-19 four weeks after receiving the J&J vaccine had to be hospitalized. There were also no deaths. 

Unlike the Pfizer and Moderna vaccines, which require two shots to achieve 95% effectiveness in preventing mild and severe COVID-19 infections, the J&J vaccine only requires one shot making it more convenient for many people. 

The J&J vaccine is the first single shot vaccine in the fight against the COVID-19 pandemic and was granted an Emergency Use Authorization by the FDA on Feb. 27, 2021. As of March 1, Johnson & Johnson has already started shipping out the vaccine nationwide.

How the Johnson & Johnson vaccine works

Similar to the Pfizer and Moderna vaccines, the J&J vaccine does not contain any COVID-19 viruses, so it cannot give you COVID-19. 

The J&J vaccine is called an adenovector vaccine. It works by modifying an existing adenovirus, a virus that causes the common cold, with the gene for the coronavirus spike protein (a protein that is found on the surface of the coronavirus). 

Once injected into the human body, the modified adenovirus cannot replicate itself or cause infections. Its job is to put its DNA into the nucleus of our cells. The spike protein gene is then read by our cell, and copied into messenger RNA, or mRNA. The mRNA then tells our cells to create the coronavirus spike proteins, which is then killed by our body’s immune system. 

Similar to the Pfizer and Moderna vaccine, this means that when the real COVID-19 virus infects our bodies, our immune system will know how to fight the infection, because it fought something that looked similar before. This adenovector technology is unique but Johnson & Johnson has a lot of experience with it; it was used for the company’s Ebola vaccine. 

According to the Centers for Disease Control and Prevention, the most common side effects for the J&J vaccine is:

  • Pain in the arm. 
  • Fatigue.
  • Headache.
  • Muscle aches.
  • Chills. 

These side effects are temporary and are more common in people 18-59 years old. If you are allergic to any of the ingredients in the J&J vaccine, you should not be vaccinated with it. Contact your medical provider for the best vaccine for you.

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Viet Fact Check has partnered with a number of community and health organizations to educate the Vietnamese-American community on the COVID-19 vaccine. The project is supported by: Progressive Vietnamese American Organization (PIVOT), Asian Health Services (AHS), the California Healthy Nail Salon Collaborative, Union of North American Vietnamese American Students (UNAVSA), Southeast Asian Resource Action Center (SEARAC), Asian American Research Center on Health (ARCH) and the Association of Asian Pacific Community Health Organizations (AAPCHO).