According to a new study published in The Lancet journal, the Pfizer vaccination is considerably less potent against the Delta variant of Covid, which is prevalent in India, than the original strain of the coronavirus.

The immune response to the variants is even lower in individuals who have only obtained one dosage, and the data suggests that a prolonged gap between dosages might dramatically lower antibodies against the Delta variant.

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After a single dose of Pfizer, 79% of patients showed a measurable neutralizing antibody response against the original strain, but this dropped to 50% for the B.1.1.7 or Alpha variation, 32% for the Delta variant, and 25% for the B.1.351 or Beta variation identified in South Africa.

The researchers note it is most important to ensure that vaccine protection remains high enough to keep as many people out of hospital as possible.

“Our results suggest that the best way to do this is to quickly deliver second doses and provide boosters to those whose immunity may not be high enough against these new variants,” says Emma Wall, UCLH Infectious Diseases consultant and Senior Clinical Research Fellow for the Legacy study.

The researchers emphasize the need for maintaining strong vaccination coverage in order to keep as many patients out of the hospital as possible.

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The proposal contradicts India’s recent statement to prolong the period between two Covishield doses from six to eight weeks to 12 to 16 weeks, citing research that showed the vaccine’s efficacy improved with time.

Critics say the government is expanding the gap to relieve pressure on its immunization campaign, which has been hampered by a lack of doses and a restricted supply of vaccinations.

According to official sources, efficacy was much higher at 81.3% (60.3-91.2) after two doses administered at a 12-week or longer interval, opposed to 55.1% (33-69.9) when administered fewer than six weeks apart, based on “available real-life evidence, mainly from the UK.” That research, on the other hand, was not based on the Delta variation.

The latest Lancet study, however, backs up the present action plan of the UK to close the vaccine dose gap, finding that after just one dose of the Pfizer-BioNTech vaccine, people are far less likely to display antibody responses against the Delta variant than the previously dominant Alpha variant, which was first discovered in UK’s Kent.

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According to Public Health England (PHE), scientists believe the Delta strain has surpassed the Alpha variant in the UK, and preliminary research shows the Delta strain may be associated with an “increased risk of hospitalization” as opposed to the Alpha.

According to the Lancet, Pfizer-BioNTech’s dose generates five times lesser antibodies against the Delta variant than the original Covid strain.

According to the Lancet, the vaccine develops fewer antibodies as people become older, and the levels of antibodies diminish with time.

The team, led by researchers from the Francis Crick Institute in the UK, analyzed The team, lead by experts from the Francis Crick Institute in the United Kingdom, looked at antibodies in the blood of 250 healthy adults who had one or two doses of the Pfizer vaccine and were followed up on three months later.

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Antibodies that impede viral entrance into cells (known as “neutralizing antibodies”) were tested against five distinct viral types.