Both vaccines in use have a shelf life of six months

Both vaccines in use have a shelf life of six months

Chethan.Kumar@timesgroup.com

Bengaluru:19.01.2021

The Union health ministry has said that both the Covid-19 vaccines — Covishield and Covaxin — being administered now in India have a shelf life of six months from the date of production, but, as reportedearlier by TOI, each vial must be used or discarded within four hours of being opened. The Centre had already procured morethan 16 million doses of the two vaccines.

Arundathi Chandrashekar, a mission director under the National Health Mission (NHM), said, “The expiry dates of these vaccines appear to be in line with the general shelf life for vaccines that we use under the universal immunisation programme (UIP).” This, another official said, gives the government enough time to plan and procure doses.

The Union health ministry has also laid out other guidelines that need to be followed to ascertain if the vaccine is good for use within six months. It has said both vaccines are ‘freeze sensitive’ and vials found frozen or frozen and thawed must be discarded immediately.

For Covishield — whose physical appearance is slightly opaque (colourless to slightly brown), the vials must be discarded if “solution is discoloured or visible particles are observed”, the ministry has said. Similarly, for Covaxin, whose appearance is whitish translucent, “presence of particulate matter or other coloration” are grounds for discarding.

“Given our experience of handling vaccines, we do not anticipate freezing of the vials as we have adequate infrastructure to store it at prescribedtemperatures(2°Celsiusto 8°Celsius),” Chandrashekar said.

Specific instructions for use of Covaxin read: Use of corticosteroids (a class of steroid hormones) and chloroquine (a type of medication), may impair antibody response.

The Centre has also advised vaccinators to discard all vials — a vial of Covishield contains10 doses and Covaxin 20 doses — four hours, and not six as state experts had suggested, after being opened given the absence of vaccine vial monitors (VVMs).

“Six hours should still be all right because the four-hour time frame was set as an additional precaution and was not standard requirement,” an official said. “Usually when open vial policy is not allowed, we can use the vial for more than six hours,whichcouldbe happening at some session sites.”