The US Food and Drug Administration FDA approved a new coronavirus SARS-CoV-2 vaccine developed by pharmaceutical company Johnson & Johnson on February 27, 2021. What is the difference between the Johnson & Johnson vaccine and the Pfizer or Moder vaccine that has already begun vaccination? Professor Maureen Ferran, who studies virology at Rochester Institute of Technology in the United States, explains this in four ways and draws attention.
First, how does the Johnson & Johnson vaccine function? Vaccines such as BNT162b2 and Moder or mRNA-1273 developed by Pfizer and Bio&Tech are RNA vaccines using mRNA, a messenger that viruses use to synthesize proteins based on genetic information. When the spike protein mRNA is administered to the human body on the surface of SARS-CoV-2, the body synthesizes the spike protein, so the basic structure of the RNA vaccine is that the human body responds and acquires immunity. mRNA administration uses special particles called lipid nanoparticles.
On the other hand, Johnson & Johnson vaccine is called a viral vector vaccine because it uses Adenovirus family (Adenoviridae) as a viral vector that carries the genetic information of the SARS-CoV-2 virus spike protein.
When some of the genetic information of the adenovirus family is updated with SARS-CoV-2 and then injected into the body, the genetic information in the virus penetrates the cells. Then, because the spike protein is synthesized in the human body, it is recognized as a foreign substance, and the immune system makes antibodies and can obtain immunity to SARS-CoV-2.
According to Professor Peran, adenovirus is harmless among vaccines, so there is no fear of proliferating in the human body or causing disease. In addition, since the only surface protein of SARS-CoV-2 is synthesized in the body, there is no worry about the outbreak of Corona 19.
RNA vaccine was first developed as a vaccine for COVID-19, but viral vector vaccines have been used since before. The vaccine for Ebola produced by Johnson & Johnson is the same virus vector vaccine developed this time.
The second is whether it works. As a result of a clinical trial conducted in the United States, Johnson & Johnson vaccine was effective in preventing corona 19 infection by 72%, as well as 86% in preventing severe disease. Meanwhile, in a test held in South Africa, the effect was 64%, but it was 82% effective in preventing severe disease.
Because of this, Professor Ferran says that although the chances of getting vaccinated against Corona 19 remain, the chances of hospitalization or death from Corona 19 are very low. In addition, according to an FDA report, the Johnson & Johnson vaccine has been shown to be effective against mutant viruses found in the UK and elsewhere.
Third is the difference with other vaccines. Pfizer and Modena vaccines should be given twice at intervals of 3 to 4 weeks, but there is a debate about whether it is necessary to inoculate a large number of people first, such as delays in access planning and vaccine acquisition. In addition, the results show that the modena vaccine is effective even if the one vaccine is half, but two doses are required.
On the other hand, the Johnson & Johnson vaccine is effective in one shot, making it attractive in situations where vaccines are scarce. In addition, some point out that Pfizer vaccine will be a logistics nightmare because it has to be stored at -70 degrees Celsius at -70 degrees Celsius, but Johnson & Johnson vaccines can be stored in a general refrigerator at -20 degrees Celsius for 2 years and stored 2 to 8 times for 3 months, making vaccination simple. You can also expect advantages.
Fourth, if so, which vaccine to choose? The Johnson & Johnson vaccine showed 72% effectiveness in US clinical trials, but Pfizer and Modena vaccines showed close to 95% effectiveness. However, Professor Ferran points out that because the original test methods are different, the effectiveness of vaccines cannot be simply compared. He also expressed the view that as many people as possible should be vaccinated to suppress the outbreak of mutant viruses rather than waiting for a vaccine to be selected. Related information can be found here.