- PPI Staff
New Delhi: The government of India has said that the decision to increase the gap between two Covishield vaccine does has been increase to 84 days after considering scientific data pertaining to behavior of adenovector vaccines.
Citing date released by Public Health England in April, 2021, Dr. N K Arora, Chairman, COVID-19 Working Group of the National Technical Advisory Group on Immunization (NTAGI), said the vaccine efficacy varied between 65% – 88% when interval between two weeks is 12 weeks and this was how the UK is supposed to have overcome the Alpha variant.
Dr Aroa said that when interval between does is increased, adenovector vaccines are seen to give better response. He said this would also ease pressure off the community as everyone cannot take the dose precisely in 12 weeks for various reasons.
Dr Arora revealed that the earlier bridging trial data available was used to make the decision of four weeks between two doses.
The increase in gap between two does, however, is limited to only the Covishield vaccine. Whereas the Covaxin second dose has to be taken within 4 weeks and delay would lead to disruption of antibody formation.
At best, the two different gap periods between the two vaccines presents a logistical nightmare in administrating the vaccine at a time when supply of none of the vaccines is stable. The Modi government which made its decisions on the basis of fudged pandemic data, had erroneously and foolishly assumed that India had beaten the vaccine. The PM claimed victory at the international fora at the last WEF.
As a result the government failed to place orders for the vaccine early and acted only in January this year. In addition, the government had almost 8 months to beef up the vaccine manufacturing infrastructure to meet the needs of 1.3 billion citizens, but failed to do so. This has led to the allegation that the gap between two dose of Covishield was increased to deal with the short supply.
Dr. Arora said that reports from UK suggest that a single dose of Covishield vaccine gives only 33% immunity while two doses give about 60% protection. This raises the question whether by increasing the gap the population is exposed to the virus with a mere 33% immunity despite being vaccinated. Would it not be wiser to therefore give the second dose as early as possible- much before the present 84 days?
At the same time Dr Arora says that if there is new evidence showing that a shorter gap is more effective, then the gap could be reduced. In other words, he is admitting that even the data used to make the decision is not conclusive and might change. Clearly, the whole gap increasing business is a work in progress and not final.