New Delhi, Dec 5 (IANS): Just hours after Haryana Health Minister Anil Vij, who was administered a dose of Covaxin last month, confirmed he has developed Coronavirus symptoms, the Union Health Ministry on Saturday clarified that Vij took only the first dose of the two-dose vaccine.

"The antibodies against the infection build up in a human being only after a specific number of days pass after the second dose of the vaccine is taken. Since, this is a two-dose vaccine. Minister in question has taken only one dose of the vaccine," the ministry said in a statement.

In the case of this vaccine, trial volunteers receive two intramuscular injections approximately 28 days apart.

Participants are randomly assigned to receive Covaxin or placebo. The trial is double-blinded, such that the investigators, the participants and the company are not aware of who is assigned to which group.

The statement from the ministry came after the 67-year-old minister tested positive two weeks after being given a shot of the vaccine, which is being indigenously developed by the Bharat Biotech in collaboration with the Indian Council of Medical Research, at a hospital in Ambala as part of the third phase of the trial.

"I have been tested Corona positive. I am admitted in Civil Hospital Ambala Cantt. All those who have come in close contact to me are advised to get themselves tested for corona," Vij tweeted on Saturday.