Covid: Pfizer vaccine produces nearly six times fewer antibodies against delta variant, shows study
The level of antibodies produced also declines with age and over time.
The coronavirus vaccine developed by pharmaceutical company Pfizer is likely to produce 5.8 times lower levels of antibodies against the Delta variant of the infection, according to a research published in the medical journal Lancet on Thursday. The Delta variant was first detected in India.
The study, which was conducted on participants who had received both doses of the vaccine, also showed that the levels of antibodies generated decrease with age and they decline over time. This observation makes a case for a booster dose of the vaccine. However, no correlation was observed for a person’s gender or body mass index.
The study analysed antibodies in the blood of 250 healthy people who received either one or two doses of the Pfizer-BioNTech Covid-19 vaccine, up to three months after their first dose. The Pfizer vaccine is expected to be available in India soon and is likely to be available for children as well.
The B.1.617.2 variant, now known as Delta, was responsible for the devastating second wave of the pandemic in the country, a government study has shown. Meanwhile, On Tuesday, the World Health Organization said that only the B.1.617.2 strain in India was now considered “of concern”.
‘Prior infection cuts infection risk for up to 10 months’
Meanwhile, a separate study published in Lancet has shown that the risk of contracting the coronavirus is substantially reduced for up to 10 months following the first infection, PTI reported.
The research looked at rates of Covid-19 infections among over 2,000 care home residents and staff in England, between October last year and February this year.
It found that residents with a previous infection were 85% less likely to get the virus than those who had never been infected. On the other hand, staff members with past infection were 60% less vulnerable.
Based on the antibody test results, out of the 634 people who had been previously infected, reinfections occurred in only four residents and 10 members of staff, according to the study.