COVID-19 vaccine more effective with 2nd dose after 12 weeks, says Kashmir doctors' body

It said that there is evidence that a longer interval between the first and second dose of Oxford vaccine provides a stronger immune response.

Doctors’ Association Kashmir (DAK) on Tuesday claimed that COVID-19 vaccine is more effective when the second dose is given 12 weeks after the first shot.

DAK President and influenza expert Dr Nisar ul Hassan said in a statement that the longer interval between the doses gives more protection.

He said that there is evidence that a longer interval between the first and second dose of Oxford vaccine provides a stronger immune response.

The DAK President also cited a study published in Lancet he said had “revealed that the vaccine efficacy was 82.4 percent among those who received the second dose after an interval of 12 weeks, whereas the efficacy was only 54.9 percent among those with an interval of less than 6 weeks”.

The first dose was 76 percent effective from day 22 to 90 days post vaccination and the protection did not wane during this initial three month period, Dr Nisar said.

He warmed that delaying the second dose would allow more people to get the first dose sooner and would save more lives.

“If enough people get vaccinated quickly, we will achieve the herd immunity sooner that would bring an end to the ongoing public health crisis,” he added.

While the longer interval between the doses is beneficial in terms of building a broader and long lasting immune response, India continues to administer the second dose of Oxford vaccine- Covishield at 4 week interval added the DAK President added.

He said that the Lancet study “also showed that a single dose of the vaccine significantly reduced the transmission of the virus with 67 percent reduction in positive swabs among those vaccinated”.

Dr Nisar said it is the first clinical evidence so far that COVID-19 vaccine provides the sterilizing immunity that prevents the inoculated person from being able to infect others. 

 “This new finding is significant because it will enable us to lift the social distancing measures and lockdowns more rapidly than would otherwise be the case,” he added.