Compared with last year's original version of COVID-19, the delta variant strain from India caused more trouble in the world. In 132 countries, the number of confirmed cases in the United States and other countries increased significantly, even breaking through vaccine protection.
According to the CDC CDC report, the delta mutant strain is by far the most dangerous and easiest to spread COVID-19. The infection rate is comparable to that of varicella. The level of R0 8-9 means that 1 people can infect 8 or 9 people, while the early new crown can only infect 2 people.
Not only the transmission speed is fast, but also the virus content has increased,The study said that people infected with delta virus had 1000 times more virus particles in the upper respiratory system than those infected with the original coronavirus that initially caused the pandemic.
Now the Japanese research team has also done more in-depth research in order to understand the harm of delta mutant strain.
A team led by Kei Sato, an associate professor at the Medical Research Institute of Jingdong University in Japan, artificially created a virus carrying p681r mutation
Japanese studies have found that viruses with p681r mutation have larger syncytia after decomposing human cells,It is 2.7 times larger than the syncytial produced by the original COVID-19.The larger syncytium means stronger pathogenicity and more serious harm.
In a mouse experiment, they found that mice infected with the P681R mutant virus were lighter in weight and 4.7% to 6.9% less than the original version of COVID-19.