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Johnson & Johnson COVID-19 Vaccine

Published on Apr 26, 2021   -  4 min read


The COVID-19 pandemic reminds us of the importance of immunization, which can save millions of lives. The newly approved, Johnson & Johnson COVID-19 vaccine, is a critical tool for fighting this global pandemic. To know more, have a look at this article.

Johnson & Johnson COVID-19 Vaccine


Johnson & Johnson COVID-19 vaccine is a single dose vaccine developed by the Janssen Pharmaceutical Companies of Johnson & Johnson to prevent COVID-19. It is the third COVID-19 vaccine that got approved after the two-shot regimens of Pfizer- BioNtech and AstraZeneca, and it is the first single-dose vaccine.

Why Johnson & Johnson COVID-19 Vaccine?

The data from the Phase 3 ENSEMBLE study shows that this vaccine is 85% effective in preventing COVID-19. It provides protection 28 days after the vaccination. The Johnson & Johnson company is planning to apply for the Biologics License Application with the FDA. It uses the AdVac vaccine platform, which is a unique technology that was used to develop Janssen’s European Commission-approved Ebola vaccine.

What Is the Phase 3 ENSEMBLE Study?

The study was enabled to understand the safety and efficacy of this COVID-19 vaccine in protecting against both moderate and severe cases. The efficacy was evaluated on day 14 and day 28 after vaccination.

How Is the Vaccine Stored?

Johnson & Johnson vaccine is compatible with standard vaccine storage and distribution channels with ease of delivery to remote areas. The vaccine remains stable for two years at -4 degree F (-20 degree Celsius) and a maximum of three months at temperatures of 36 to 46 degree F (2 to 8 degree Celsius). The vaccine should not be re-frozen if distributed at a temperature of 36 - 46 degrees F (2 to 8 degrees Celsius).

What Age Group Can Have This Vaccine?

Johnson & Johnson COVID-19 vaccine is recommended for individuals of age 18 years and above.

Who Should Not Get the Vaccine?

Individuals who have a severe allergic reaction to any of the ingredients of this vaccine.

How Is the Vaccine Given?

Johnson & Johnson vaccine is a single-dose vaccine. It is administered intramuscularly in the deltoid muscle.

What Should You Mention Before Getting Vaccinated?

Before getting vaccinated, you have to inform if you:

How Is Johnson & Johnson Vaccine When Compared to the Other Two Vaccines?

Pfizer and Moderna require two shots to get the maximum protection against the COVID-19. But in the case of the Johnson & Johnson vaccine, it is a single-shot vaccine. If you are worried about the side effects, you should go for the Johnson & Johnson vaccine, as the side effects are minimal compared to Pfizer and Moderna vaccines. According to Pfizer, about 3.8% of their clinical trial participants experienced fatigue and 2% experienced headaches. According to Moderna, 9.7% of the trial participants experienced fatigue and headache. According to the Centre for Disease Control and Prevention, the side effects from the second shot will be more than the first shot.

In trials of both Pfizer and Moderna, more people experienced side effects after the second shot. You are bound to get the second shot even if you experience side effects from the first shot. The main side effects of the Johnson & Johnson vaccine are pain at the injection site and flu-like symptoms.

Other Than the Side Effects, How Are Pfizer and Moderna Different From the Johnson & Johnson Vaccine?

In Pfizer and Moderna vaccines, mRNA is introduced into your body, unlike the traditional vaccines where a weakened or inactivated germ is injected into the body. The mRNA is a code that serves as an instruction manual to the immune system to identify the virus and attack it. In the case of the Johnson & Johnson vaccine, instead of using mRNA, it uses a disabled adenovirus to provide the instructions on how to attack the virus.

Are There Benefits From the Technology Used in Johnson & Johnson Vaccine?

Yes, the biggest advantage is that Johnson & Johnson COVID-19 vaccine can be kept at refrigerator temperatures for months, and it will be stable. In contrast, Pfizer and Moderna vaccines are not as stable as Johnson & Johnson vaccine, and they require very cold storage temperatures. Once Pfizer and Moderna are taken out of cold temperatures, their window time is short, but it is not the case in Johnson & Johnson vaccine. Hence it is better to maintain and deliver to different parts of the country, especially for the rural areas.

What Are the Side Effects of the Johnson & Johnson Vaccine?

The side effects that have reported include :

There can be general side effects like other vaccines have:

There is also a report saying that there can be severe allergic reactions.

What Can Be the Signs of a Severe Allergic Reaction?

The signs of a severe allergic reaction include:

These signs are not the expected side effects. But when serious these unexpected side effects may occur. The clinical trials of the Johnson & Johnson vaccine are still being studied.

How Effective Is Johnson & Johnson COVID-19 Vaccine?

Why Has the Johnson & Johnson COVID-19 Vaccine Temporarily Stopped?

The Federal Health Authorities recommended temporarily stopping the Johnson & Johnson vaccine while they were investigating a potential link to the very rare blood clots. CDC and FDA are reviewing the six reported cases of rare and severe types of blood clots that developed after getting vaccinated. Hence there is a temporary pause in administering the vaccine.


No vaccine can be 100% effective. The only thing is that it reduces the severity of the disease. That is the most important factor from a vaccine. Johnson & Johnson COVID-19 vaccine was 85% effective in preventing hospitalizations and death. So, if you have access to get any vaccine, you should get it. Even if it is not 100% effective, you are less likely to have severe disease.

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26 Apr 2021  -  4 min read




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