Mixing booster shots effective against Omicron, claims Shanghai researchers
MIXING different coronavirus vaccine booster shots can help in the fight against Omicron variant, the National Center for Infectious Diseases located in Shanghai-based Huashan Hospital said.
In an article published in the Emerging Microbes & Infections journal, Dr Zhang Wenhong, the head of the center, said that booster shots can partially decrease the neutralizing antibody of the Omicron variant in a human body.
However, the possibility of failure was still higher than in the other variants, which means that a certain level of transmission will exist even after the third shot, the article claimed.
However, the booster jabs can significantly cut the incidence of severe and critical cases.
After November 26, when the new variant B.1.1.529 was named Omicron by the World Health Organization, it has accounted for about 73 percent of new infections in the United States within four weeks, compared with about 13 percent a week ago, the study said.
In the United Kingdom, the Omicron cases are doubling every 48 hours.
That could be because the immune barrier formed by the natural infection had been broken by Omicron, the paper argued.
International research suggested that there was a significant decrease in the protection power against Omicron after two shots of COVID-19 vaccines of any type.
The team found that the neutralizing antibody titer of two shots against Omicron dropped to 6.04, and the neutralizing antibody titer of 80 percent of serum specimen was below the lower limits.
For the first time, the team assessed the neutralizing level against Omicron among those who had taken two shots of the inactivated vaccines and people who had been inoculated with the third shot of the same vaccines and the third shot of recombinant DNA protein vaccines.
They found that the neutralizing antibody titer in serum among people inoculated with the booster shot of the same inactivated vaccines as the previous two against the original COVID-19 strain, the Delta strain and the Omicron strain rose to 285.6, 250.8 and 48.73, respectively, 14 days after they were vaccinated.
But it shot up to 1436, 1501 and 95.86 if the third shot was recombinant subunit protein vaccine heterologous, the team found.
It meant that the third shot of COVID-19 homology and heterologous vaccines lifted the neutralizing power against Omicron by 8.07 times and 15.87 times, respectively.
The positive rate of neutralizing antibody titer in serum specimen against Omicron was 100 percent among people taking the booster shot in spite of their types, which meant that the booster could provide a certain level of protection while the level of antibody varies, according to the thesis.