Vaccine Safety – J&J vaccine
In previous posts, we explored vaccine safety and the newest COVID-19 mRNA vaccines. In this post, we explore the newest COVID-19 vaccine available.
What are vaccines?
A vaccine is a biological preparation designed to provide our body with active immunity to particular infectious pathogens when appropriately administered.
Vaccines stimulate immune responses and build immunological memory. Once we've received a vaccine, our body's immune system can recall a specific pathogen's identity, even years later, and effectively fight the pathogen. You can learn more about how vaccines work, ingredients in vaccines, and general comments about their safety in our previous blog posts (1,2).
How does the newest vaccine work?
Unlike the other two vaccines available, the newest vaccine by Janssen (J&J) does not use the latest mRNA technology to build our system’s immunity. Rather, the J&J vaccines use a more traditional mechanism to trigger an immune response.
The J&J vaccine is a recombinant vaccine (1,2). It contains a safe adenovirus vector that has been engineered to make a harmless to us version of the spike protein found on the SARS-CoV-2 virus. By doing so, it serves as a dummy to train our immune system to better combat the SARS-CoV-2 virus (1).
As we know, once a virus enters a host (our body), the protein binds to the host's healthy cells, facilitating the entry of viral RNA into host cells and forces the healthy cells to produce copies of the virus. When this occurs, we have an infection.
Once we're infected, our body's white blood cells multiply to stop the virus, but that takes time (1). While most healthy individuals successfully fight off the SARS-CoV-2 virus infection, many individuals with underlying health concerns cannot fight off the infection, causing them to succumb to the disease.
We know our body’s immune system can destroy the virus if given enough time. The J&J vaccine primes our body to respond more effectively by expanding those immune cells (white blood cells) that can recognize and then destroy the SARS-CoV-2 virus.
Unlike the Pfizer-BioNTech and Moderna vaccines, the J&J vaccine does not use mRNA. Instead, it uses an adenovirus vector to get the needed instructions to our cells.
The adenovirus vector is essentially a harmless cold virus that cannot replicate itself in our body nor can it cause disease. Therefore, it has been used as a platform for a variety of vaccines. Its safety has been demonstrated by several clinical studies with more than 100,000 participants (1).
The adenovirus vector in the J&J vaccine has been engineered to make a harmless-to-us piece of protein that’s the same as the protein present in the SARS-CoV-2 virus. The protein then teaches our immune cells to identify and combat the SARS-CoV-2 virus.
Next, our body’s immune system will recognize the protein as foreign (i.e., doesn’t belong to us) and develop an immune response including antibodies that bind to the protein and eliminate the pathogen. As we’ve covered in a prior post, our body’s immune system remembers how to fight and eliminate unwanted pathogens.
Now that our body’s immune system has been trained and remembers how to identify the protein found on the SARS-CoV-2 virus that causes COVID-19, if we are exposed to the SARS-CoV-2 virus, our body will effectively produce antibodies that can binds to the protein on the SARS-CoV-2 virus and eliminate the virus thus protecting us from the virus (1).
What ingredients are in the J&J COVID-19 vaccine?
Janssen (J&J) COVID-19 Vaccine (1).
- recombinant, replication-incompetent adenovirus type 26 expressing the SARS-CoV-2 spike protein
Inactive ingredients (including stabilizer, buffer solution, and salts):
- 2-hydroxypropyl-β-cyclodextrin (HBCD)
- citric acid monohydrate
- sodium chloride
- trisodium citrate dihydrate.
How does the J&J COVID-19 vaccine differ from mRNA vaccines?
There are a couple of core differences:
- The vaccines use a different mechanism to deliver the spike protein to elicit an immune response.
- The mRNA vaccines require specific cooling requirements that can make transportation difficult.
- The mRNA vaccines require two doses, weeks apart to work effectively, the J&J vaccine only requires one dose.
How effective is the J&J vaccine?
In the United States, the vaccine was 74.4% effective and 72% effective in preventing moderate to severe/critical COVID-19 occurring at least 14 days and 28 days after vaccination, respectively (1).
Has the J&J vaccine been tested, is it safe?
Yes. While these may be new vaccines, released in an emergent circumstance, the U.S. Food and Drug Administration (FDA) still has strict quality, safety, and efficacy requirements that Janssen, Pfizer-BioNTech, and Moderna met (1).
Tens of thousands of individuals received the vaccines by participating in clinical studies to ensure the vaccines' safety and efficacy (1).
Based on the current data, all currently available vaccines are safe and effective in preventing severe COVID-19 infections.
Has anyone died from getting the vaccine?
At the time of publication, there are no confirmed cases of an individual dying due to any of the COVID-19 vaccines (1).
There have been a handful of adverse reactions that have required immediate medical assistance, so it's important to talk with your doctor before getting vaccinated if you have a history of adverse reactions to vaccines.
Sadly, more than 500,000 Americans have died from complications related to COVID-19 infections.
Who benefits most from the COVID-19 vaccines?
Though society as a whole benefit from herd immunity, which results from widespread vaccination, there are subgroups that are more acutely impacted by COVID-19 infections:
- adults 65 and older (1)
- individuals with medical conditions such as cardiovascular disease, diabetes, chronic respiratory conditions, obesity, compromised immune systems, and more (1).
Can anyone receive a vaccine, which vaccine should I get?
At the time of publication, the COVID-19 vaccine supply is still somewhat limited as production continues to gear up, so government health agencies are prioritizing vaccine distribution based on an individual's risk factors, occupation, age, and other specific criteria.
Since supply is limited, you should get whichever vaccine is available to you and recommended by your physician.
Individuals who've had an allergic reaction to vaccines in the past or who have specific health conditions should speak with their doctor before receiving a vaccine.
How can I sign-up to get vaccinated?
At the time of publication, vaccine distribution is routing through local health departments but may vary, state to state.
To learn more about the COVID-19 vaccine distribution process in your area, reach out to your local health department.
The good news.
We have another safe, effective vaccine able to help protect us from COVID-19. Additionally, this single-dose vaccine doesn’t require specialized refrigeration, which means more people can get the vaccine quicker and receive immunity benefits faster.
With wide-spread vaccination and other best health practices like hand washing, mask-wearing, and social distancing, we can stop the spread of COVID-19