[ad_1]
Chinese media quoted public health experts as saying that vaccination can trigger an ADE reaction, which aggravates the condition. (Schematic) Image: New head shell profile photo
Wuhan’s pneumonia epidemic remains serious. So far, more than 25.65 million people have been diagnosed worldwide and 850,000 have died from the disease. Countries are looking forward to the emergence of effective vaccines. The scientists noted that the major Wuhan pneumonia vaccines in China and Russia have a common flaw. Both use common adenovirus as a carrier to develop vaccines. Many people have been infected with this virus in the past and antibodies may exist in their bodies. It causes the human body to attack the adenovirus vector rather than the Wuhan pneumonia virus itself, greatly reducing the effectiveness of the vaccine and may even increase the risk of AIDS.
The Wuhan pneumonia vaccine developed by China’s CanSino Biologics was approved by Beijing authorities in June for internal use by the People’s Liberation Army. The “Sputnik V” vaccine developed by the Gamaleya Institute in Russia was also approved by Moscow authorities in August, making it the world’s first Wuhan pneumonia vaccine.
According to a Reuters report, the two vaccines have in common that they both use recombinant adenovirus type 5 (Ad5) as a carrier, and the Russian vaccine also uses a less common adenovirus type 26 as a substrate. The recombined adenovirus will no longer cause harm to the human body. The researchers have implanted the gene for the Wuhan pneumonia virus into a harmless adenovirus vector to become a vaccine. When the vaccine enters the human body, it will stimulate the body to produce an immune response and produce antibodies. It fights the Wuhan pneumonia virus and then produces immune memory.
However, because adenovirus type 5 is a fairly common virus, most people have been infected with this virus during the growth process, and there are antibodies in the body. Scientists are concerned that after vaccinating the human body, it may induce the immune system to attack the adenovirus vector. Instead of the Wuhan pneumonia virus itself, which leads to less effectiveness of the vaccine. To solve the problem of efficacy, the “Sputnik V” vaccine will be administered in two doses, the first dose will be adenovirus type 26 and the second dose will be adenovirus type 5.
Experts noted that currently about 40% of Chinese and Americans have antibodies against adenovirus type 5. If they are in Africa, this number reaches 80%. Dr. Hildegund Ertl, director of the Vaccine Center at the Wistar Institute in Philadelphia, USA, said: “I think that people without antibodies in their bodies will have very good immune effects, but many people actually have Have.”
Anna Durbin, a vaccine researcher at Johns Hopkins University in the United States, questioned: “Adenovirus type 5 makes me suspicious because many people are immunized. I am not sure what their strategy is. Perhaps the effectiveness of the vaccine will not reach the 70%, maybe only 40%, which is better than nothing. “
In addition to doubts about their effectiveness, some scientists believe that vaccines that use adenovirus type 5 as a carrier may also increase the risk of infection with the human immunodeficiency virus (HIV) that causes AIDS. An HIV vaccine test conducted by Merck & Co. in 2004 using adenovirus type 5 as a carrier showed that people who have pre-immunity in their bodies are more likely to become infected with HIV.
In response, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases (NIAID) and other researchers noted in a 2015 article that the side effects of HIV infection can be limited to the HIV vaccine. But at the same time they also cautioned that all adenovirus type 5 vaccine trials in high-risk populations must be carefully monitored.
The pneumonia epidemic in Wuhan remains serious. So far, more than 25.65 million people have been diagnosed worldwide and 850,000 have died from the disease. Countries eagerly await an effective vaccine. The scientists noted that the major Wuhan pneumonia vaccines in China and Russia have a common flaw. Both use common adenovirus as a carrier to develop vaccines. Many people have been infected with this virus in the past, and antibodies may exist in the body. It causes the human body to attack the adenovirus vector rather than the Wuhan pneumonia virus itself, greatly reducing the effectiveness of the vaccine.
The Wuhan pneumonia vaccine developed by China’s CanSino Biologics was approved by Beijing authorities in June for internal use by the People’s Liberation Army. The “Sputnik V” vaccine developed by the Gamaleya Institute in Russia was also approved by Moscow authorities in August, making it the world’s first Wuhan pneumonia vaccine. The common point of these two vaccines is that they both use recombinant adenovirus type 5 (Ad5) as a vector, but since adenovirus type 5 is a fairly common virus, most people have become infected during their growth. This virus has antibodies in the body. Scientists are concerned that after vaccinating the human body, it may induce the immune system to attack the adenovirus vector, rather than the Wuhan pneumonia virus itself, reducing the effectiveness of the vaccine.
[ad_2]
