A study published in the journal Nature has suggested that the Delta variant can escape antibodies that target some parts of the virus. The results from the study explain the reduced effectiveness of vaccines against the Delta variant, in comparison with other variants.

The variant is said to be nearly 60% more contagious than the Alpha variant, the strain first identified in the UK. It is also twice as contagious as the original strain. The study noted the Delta variant to be barely sensitive to a single vaccine dose, and confirmed previous findings that the variant can partly evade the immune system, though to a lesser extent compared to the Beta variant, which was first found in South Africa.

Investigators assessed samples from 59 individuals who had received both doses of the AstraZeneca or Pfizer-BioNTech COVID-19 vaccines. Samples from 10% of individuals vaccinated with one dose of either of the shots were able to neutralize Delta and Beta variants in lab tests. However, a second dose increased the number to 95%... (ET Healthworld – NYT News Service, July 9, 2021)