They reveal the true effectiveness of a dose of Pfizer against the new variants

Only one dose of vaccine against coronavirus of Pfizer a minor efficiency in front of variants discovered in England, India and South Africa compared to the original strain, according to a laboratory study and released this Friday.

However, the researchers warned that these the results are inconclusive and that more will be needed studies among the real population, according to the article published in the medical journal The Lancet.

In the lab, scientists tested the production of protective antibodies, called neutralizers, in people vaccinated with Pfizer / BioNTech, by putting your blood samples in contact with different versions of the virus discovered in Wuhan (China) and the one that dominated Europe in mid-2020, the Alpha variant (detected in England), Beta (in South Africa) and Delta (in India).

“After only one Pfizer / BioNTech assay, 79% of people had a detectable antibody response against the original strain, but it was 50% against the Alpha variant, 32% against Delta and 25% against Beta ”, according to the Francis Institute Crick of London, author of the study with the British National Institute for Health Research (NIHR), the AFP news agency reported.

Emma Wall, researcher of the study said that “it is essential to ensure sufficient protection to avoid hospitalizations as much as possible”, noting that the “results suggest that the best way to achieve this is to administer the drug promptly. second dose“according to a press release.

Thus, the study endorses the recent decision of the United Kingdom to reduce the interval between the two. Pfizer vaccine dose, from a maximum of three months to eight weeks for those over 50 and the most vulnerable.