The Assam Health Department had decided to send a batch of 100 vials of Covishield containing 1,000 doses of the COVID-19 vaccine to a laboratory after this batch was found frozen in the vaccine storage unit of Silchar Medical College in the state's Cahchar district.
A notice has been sent to the medical college over alleged improper storage of the vaccine made by the Serum Institute of India, an official said.
The Health Department has not said this batch of vaccine has been wasted as it will wait for the report of the laboratory to check its potential efficacy.
The incident happened on Saturday, the first day of the vaccination drive across India.
According to the guidelines of the Pune-based Serum Institute, the vaccine needs to be kept at a temperature between 2 and 8 degree Celsius.
According to Assam's cold chain system, the vaccines are being transported and kept stored in ice-lined refrigerators as specified by the universal immunisation programme for transporting and storing any vaccine.
These refrigerators, due to an extra lining of dry ice, continue to maintain the required temperature even if there is no power supply for a long time.
"An investigation has been initiated to see where the lapse had taken place. There are chances of the vaccine getting frozen while being carried to the hospital or while kept stored in the hospital," a senior health department official said.