Johnson & Johnson’s Covid Vaccine Shot has a slightly lower efficacy rate than the first shots produced by Moderna and Pfizer-BioNTech. Many experts feared the new shot might be viewed by some Americans as the inferior choice.
However, something different is happening since its rollout. People are eager to get it because they want the convenience of a single shot. And public health officials are enthusiastic about how much faster they could get a single shot distributed, particularly in vulnerable communities.
“If there are individuals who may not like needles, who may have concerns about returning for a second shot, who may not want the inconvenience of scheduling a second appointment, or who may be concerned that there isn’t enough supply of the vaccine at the moment for a second shot — for those individuals, that convenience of being done [after one dose], fully vaccinated, is really important,” says Dr. Leana Wen, an emergency physician and professor at George Washington University.
Although it has a lower overall efficacy rate in the U.S. — 72%, compared with roughly 95% for the others, but experts don’t consider these numbers as useful, because companies had conducted clinical trials in different places at different times.
The Johnson & Johnson vaccine also can be kept at normal refrigeration temperatures for three months. This makes it ideal for distribution at nonmedical sites such as stadiums and convention centers.
“There are circumstances in which it is going to be a really good option or maybe the best option,” said Dr. Matthew Daley, a senior investigator at Kaiser Permanente Colorado’s Institute for Health Research and a member of the Centers for Disease Control and Prevention’s independent vaccine advisory committee.
Moderna and Pfizer vaccines use mRNA, or messenger RNA, to deliver bits of genetic code to cells. This code serves as a sort of instruction sheet — telling cells how to make a harmless piece of the spike protein that sticks out of the surface of the coronavirus.
Johnson & Johnson vaccine is called a viral vector vaccine. To create this vaccine, the Johnson & Johnson team took a harmless adenovirus – the viral vector – and replaced a small piece of its genetic instructions with coronavirus genes for the SARS-CoV-2 spike protein.
After this modified adenovirus is injected into someone’s arm, it enters the person’s cells. The cells then read the genetic instructions needed to make the spike protein. After this, vaccinated cells make and present the spike protein on their own surface.
Foreign proteins are noticed by the person’s immune system, and it starts making antibodies against them. Such antibodies will protect the person if they are exposed to SARS-CoV-2.
The adenovirus vector vaccine can not replicate in human cells or cause disease. Thus, it passes the safety test. And the SARS-CoV-2 spike protein cannot cause Covid–19 without the rest of the coronavirus.
This approach is not new. Johnson & Johnson used a similar method to make its Ebola vaccine, and the AstraZeneca-Oxford Covid-19 vaccine is also an adenovirus viral vector vaccine.
Experts believe that there are circumstances in which it is going to be a really good option or maybe the best option.
The Food and Drug Administration found the Johnson & Johnson Covid-19 vaccine found as 72% effective at preventing all Covid-19 and 86% effective at preventing severe cases of the disease. A vaccinated person may still get sick, but they are less likely to need hospitalisation or to die from Covid-19.