• Stodia Jackson

Ingredients in the Johnson and Johnson COVID-19 Vaccine: How Does it Differ from Pfizer and Moderna?

The Johnson and Johnson (J & J) COVID-19 vaccine makes use of existing technology that utilizes adenoviruses as vectors (vehicles) that transport a key part of the SARS-CoV-2 virus particles into the body.

Adenoviruses are a common cause of mild respiratory infections. They are used in vaccine development by modifying the virus particles so that they produce an essential building-block of the COVID-19 virus. The modified adenovirus is harmless, and is also referred to as a cold virus. When introduced into the body, it causes an immune response where if one is later infected with the real COVID-19 virus, the immune system is able to recognize and fight the infection.

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While J & J uses adenoviruses as vectors, the Pfizer and Moderna vaccines use new technology that uses genetic material (mRNA) that codes for parts of the COVID-19 virus. When introduced into body cells, pieces of these parts are replicated, and this causes an immune response. The mRNA genetic material breaks down easily, hence it is quickly removed from the body cells.

Storage Requirements

The Pfizer and Moderna vaccines require a cold chain storage, which means that they need to be kept at very cold temperatures during both the distribution and administration process because the genetic material (mRNA) easily breaks down. This has created challenges during power outages or technology failures, placing health care workers administering these vaccines in a difficult position. The Johnson and Johnson vaccine does not require the cold chain storage, which means it can be administered at a larger scale in more public health centers and it can be stored at regular refrigerator temperatures for at least three months.

Vaccine Dosage

Both the Pfizer and Moderna vaccines require two-dose shots. The Pfizer dose is 30 micrograms with a 21 day interval between the doses, while the Moderna vaccine contains 100 micrograms of the dose with a 28 day interval between the doses. However, the J & J vaccine is a single dose. Data released by Johnson & Johnson showed that a one dose shot was 66% effective in preventing moderate to severe symptoms of COVID-19 and 100% in preventing COVID-19 related hospitalizations and deaths.

Side Effects

There have been side effects reported in individuals who have received several types of COVID-19 vaccines. On the 13th of April, 2021 the United States paused the J & J vaccine due to reported cases of blood clots. The pause was lifted on the 23rd of April after investigations by the FDA and CDC. However, two new cases of blood clotting have since been reported and are under investigation by the CDC. As this is an ongoing investigation, current data will continue to be updated.

Cases involving anaphylaxis caused by the Pfizer and Moderna vaccines have also been reported; as a result, the CDC encouraged monitoring for about 15 minutes after vaccination and for at least 20 minutes for those with a history of severe allergies. With the J & J vaccine, there has been one case of a severe anaphylaxis reaction reported so far. However, it is important to note that it will take more time for comprehensive results to be attained regarding the side effects of any of the vaccines.


Speaking Plainly

  • The Johnson and Johnson vaccine uses adenoviruses as vectors to create an immune response, while Pfizer and Moderna vaccines use genetic material (mRNA) technology to create immunity.

  • Evidence from the use of the Johnson and Johnson, Pfizer and Moderna vaccines has largely shown positive results thus far, however these results vary in different regions of the world. In addition, the J & J vaccine is currently under investigation as a result of blood clotting cases reported in 17 individuals at the time of writing this article.

  • More time is still needed to gather information on the long term effects and efficacy of the different vaccines in different contexts and in dealing with the different strains of the SARS-CoV-2 virus in different parts of the world.