The World Health Organization (WHO) has further delayed the emergency use authorisation (EUA) for Covaxin, the Covid vaccine developed in India, as the global body has sent more technical queries to its manufacturer Bharat Biotech, according to sources. This delay is likely to adversely affect Indians', especially students', international travel plans.

Without EUA, Covaxin will not be considered an accepted vaccine by most countries around the world. WHO's queries for Bharat Biotech comes despite the Hyderabad-based drug maker asserting that it has submitted all data required for clearance.

The indication of a delay comes merely days after the Union Health Ministry hinted that the global body was likely to give its nod anytime soon.

"There is a procedure of submitting the documents for approval. WHO's emergency use authorisation to Covaxin is expected soon," Dr Bharati Pravin Pawar, Union Minister of State in the Health Ministry, had said last Friday, according to an ANI report.

Earlier, Dr VK Paul, Chairperson of the National Expert Group on Vaccine Administration, had also said that WHO's approval for Covaxin was likely to come before the end of this month.

According to Bharat Biotech, Phase III clinical trials of Covaxin had demonstrated an efficacy rate of 77.8 per cent.

Covaxin, along with Covishield, was the vaccine first deployed by India in its massive nationwide inoculation drive against COVID-19 launched in January this year. Others like the Russia-made Sputnik were added to the country's armoury only later.

Covishield is the only India-made vaccine on the WHO list now. It is manufactured by the Serum Institute of India in Pune and was developed by researchers at Oxford University and pharmaceutical firm AstraZeneca.

The WHO has, till now, also approved vaccines manufactured by Pfizer-BioNTech, Johnson and Johnson, Moderna, and Sinopharm.