A new study has said that the Covid-19 vaccine developed by Pfizer-BioNTech produces lesser antibodies against the Delta variant. The variant was first detected in India. It is highly infectious. It increases the risk of hospitalization. The study, published in Lancet, said that those fully vaccinated with Pfizer drug develop five times lower levels of antibodies. This is not the case with the original strain. The drug is effective against the original strain. The findings came to light during a new laboratory study. The study is underway to decide on administering booster shot to those fully vaccinated with Pfizer’s drug. Pfizer’s vaccine is a two-shot drug.
The study said that response in those vaccinated with one dose was very low against the Delta variant. Pfizer developed a quantifiable neutralizing antibody after the first dose against the original strain found in China. Nearly 79 percent of people developed an antibody that kills the virus after the first dose. However, this fell to 32 percent after a single dose against the Delta variant. The same was 50 percent for the Alpha variant and 25 percent for the Beta variant of the virus. The data showed that levels of antibodies decreased with increasing age. It, however, said that vaccine is the most effective shield against the virus. It lowers the risk of hospitalization. It also prevents severity.
The study said that laboratory findings only provide a guide to how the virus evolves. The results do not predict the efficacy of vaccines. It called for detailed prospective population studies to know the effectiveness of vaccines. The study supports plans to cut the gap between two doses of vaccines. There are talks about reducing the gap between two doses in many countries. Notably, England has already reduced the gap. The study involved researchers from the London-based Francis Crick Institute. Researchers tested Pfizer-induced antibodies’ ability to prevent the entry of the virus into the body. The Delta variant is mainly dominant in India and parts of the UK. Researchers are now planning to extend the study to those vaccinated with the vaccine developed by Oxford/AstraZeneca.