The Delta variant is eight times less sensitive to antibodies generated by Covid-19 vaccine compared to the original Wuhan strain, found a study conducted on 100 healthcare workers across three centres in Delhi, including the Gangaram Hospital.
The study ‘Sars-Cov-2 B.1.617.2 Deltavariant Emergence and Vaccine Breakthrough: Collaborative Study’ also found that the variant has much higher capacity to infect more people than the Wuhan strain.
The collaborative study from India was conducted along with scientists from Cambridge Institute of Therapeutic Immunology & Infectious Disease.
“In an analysis of vaccine breakthrough in over 100 healthcare workers across three centers in India, the B.1.617.2 Delta variant not only dominates vaccine-breakthrough infections with higher respiratory viral loads compared to non-delta infections, but also generates greater transmission between fully vaccinated healthcare workers, as compared to other variants B.1.1.7 (Alpha variant) or B.1.617.1 (Kappa variant)," the findings of the study revealed.
The study found out that the Delta variant is less sensitive to neutralising antibodies from recovered individuals, with “higher replication efficiency" as compared to the Alpha variant.
In terms of its increased transmissibility, the study said that the mutant variant has enhanced spike proteins for attachment to the lung epithelial cells, which had provided it with a much higher capacity to infect many more people than the Wuhan strain.
“From this study it appears that we have to go miles before we sleep in case of Covid-19 pandemics. These mutations are bound to happen if we lower our guard and allow ourselves to fall prey to this virus giving it an opportunity to multiply and achieve better fitness with our Covid inappropriate behavior," said Dr Chand Wattal, Chairperson, Institute of Clinical Microbiology & Immunology, Sir Ganga Ram Hospital.
“This is a straight eye opener to the fully vaccinated people that you cannot lower guard in the name of vaccination. Virus is on prowl still looking of its prey. This mutant has come back with enhanced spike proteins for attachment to the lung epithelial cells which has provided it much higher capacity to infect many more people than the Wuhan strain,” he added.