The delta variant could have "complete resistance" to the COVID-19 vaccines currently in use in Japan if it acquires certain mutations, according to research results compiled by an Osaka University team.
Of the vaccines in use in Japan, the widely administered vaccines manufactured by U.S. firms Pfizer Inc. and Moderna, Inc. were developed based on the genetic information of the novel coronavirus in the initial period of the virus's emergence.
The team led by Hisashi Arase, a professor of immunology, confirmed that the delta variant escaped some antibodies developed by these vaccines. Overall, the vaccines did maintain effectiveness against the variant.
Four specific mutations to the variant, however, could greatly reduce the effectiveness of the antibodies.
The researchers artificially added these mutations and found that the antibodies did not bond with this created delta variant. This artificial delta variant also was more infectious.
A delta variant with four such mutations has not yet been confirmed in the world, but a delta variant with three of these four mutations has been found in Turkey.
Antibodies produced based on the delta variant were confirmed to suppress the functions of the original form of the virus, the delta variant and this artificial delta variant, leading the Osaka University team to point out the importance of a vaccine to deal with the highly transmissible variant.
The development of an improved vaccine to handle the delta variant is already underway at Pfizer, Moderna and other pharmaceutical companies.
Tetsuya Mizutani, professor of virology at Tokyo University of Agriculture and Technology who was not involved with the research, said: "First, it is important to reduce the number of infected people in order to prevent mutations of the delta variant. Putting into practical use a vaccine that can handle the delta variant must also be hastened."
Read more from The Japan News at https://japannews.yomiuri.co.jp/
