“It is important to take the booster dose of the vaccine. The single dose is effective only to a specific extent; the booster dose helps maintain the effectiveness,” said public health expert Dr K Kolandaisamy. The healthcare workers who took the first shot should not hesitate anymore, as there are enough people who have been vaccinated successfully, he noted.

Researchers added that people should understand the system of trials and their designed structure, and adhere to the regulations of taking the specified number of doses.

Dr Chirag Trivedi, president, Indian Society for Clinical Research (ISCR) said it was important to know that the clinical trial process is a well-established and robust process that is done by following all regulations and guidelines. “Before according approval, the regulators thoroughly evaluate the safety and efficacy data generated from these clinical trials. To boost confidence in the clinical trial processes, it is important that the general public understands the robust measures undertaken for clinical trials,” he added.

Dr TS Selvavinayagam, Director, Public Health and Preventive Medicine, said the wastage of the vaccine depends from one site to another, as major sites that have more people turning up for vaccination see less wastage. He added that one vaccine vial of 5ml can be used for 10 beneficiaries within a period of four hours. The details of those who have been vaccinated was available in the CoWIN portal, he said, adding that they would be informed and reminded to take the second dose.