Cannot Prevent New Coronavirus, May Get HIV? Scientists Point Out the Loophole of Russian Vaccine

According to a report by 'The Washington Post' on September 1, some experts said that Russia’s high-profile vaccine for new coronary pneumonia has a potential disadvantage : because many people have been infected with adenovirus type 5 in the past, the body is also of antibodies have been produced, the new vaccine developed using the common adenovirus as a carrier may cause the human body to attack the adenovirus vector, instead of the new coronavirus after injection, which greatly reduces the effectiveness of the vaccine.

It is reported that the vaccine developed by the Gamaleya Institute in Russia, named 'Sputnik V', was approved by the Moscow authorities in August this year and became the world's first vaccine for new coronary pneumonia.

According to reports, this vaccine uses recombinant adenovirus type 5 (Ad5) as a vector. The recombinant adenovirus will no longer cause harm to the human body. Researchers and vaccine developers will implant the new coronavirus gene into harmless glands. The viral vector becomes a vaccine. When the vaccine enters the human body, it will stimulate the human body to produce an immune response and produce antibodies to fight against the new coronavirus, thereby generating immune memory.

However, because adenovirus type 5 is a fairly common virus, most people have been infected with this virus during the growth process. There are antibodies in the body. Scientists worry that after the human body is vaccinated, it may induce the immune system to attack the adenovirus vector, rather than the new coronavirus itself, resulting in reduced vaccine effectiveness.

Anna Durbin, a vaccine researcher at Johns Hopkins University in the United States, said, 'Type 5 adenovirus makes me suspicious because many people are already immune, and I’m not sure what their strategy is. Maybe the vaccine's effectiveness will not reach 70%, maybe only 40%, which is better than nothing.'

Experts also pointed out that currently about 40% of the American people have type 5 adenovirus antibodies. If they are in Africa, this number is as high as 80%.

In addition to the issue of utility, some scientists also believe that vaccines with 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 had pre-immunity in their bodies were more likely to be infected with HIV.

For example, in the trial of the adenovirus type 5 HIV vaccine developed by Merck & Co in 2004, people with existing immunity became more susceptible to the virus that causes AIDS, including the top infectious disease experts in the United States. Researchers including Dr. Anthony Fauci said in a 2015 paper that this side effect may be unique to the AIDS vaccine. But they warned that all vaccines based on adenovirus type 5 should be tested in at-risk populations, and the incidence of HIV should be monitored during and after injection.

Dr. Larry Corey, the lead researcher of the US Coronavirus Vaccine Prevention Network, said, 'I am worried that the use of these vaccines will cause other countries or populations to cause a surge in HIV, and our country is no exception.'