For those doing research, this is what I've found. Please correct me if I'm wrong.
The more I research about adenoviral vector vaccines, it's pretty clear that they only can work once. Once the body fights off that AD26 vector it would not work again if administered to the same person. I believe that is why the J&J is considered a "one and done" shot becusee a second shot or booster wouldn't be effective anyways.
It does make me wonder how they expect to have a booster in the future with Covid varients.
The Russian adenoviral vaccine uses AD26 on the first shot followed by AD5 on the second as a booster. However, the AD5 vector was proven not very effective as many people already had exposure to it over the course of their lives.
The more I research about adenoviral vector vaccines, it's pretty clear that they only can work once. Once the body fights off that AD26 vector it would not work again if administered to the same person. I believe that is why the J&J is considered a "one and done" shot becusee a second shot or booster wouldn't be effective anyways.
It does make me wonder how they expect to have a booster in the future with Covid varients.
The Russian adenoviral vaccine uses AD26 on the first shot followed by AD5 on the second as a booster. However, the AD5 vector was proven not very effective as many people already had exposure to it over the course of their lives.