The Food and Drug Administration (FDA) has recalled 110 vials of the Sinovac vaccine after finding they had congealed during storage.
The FDA reported yesterday that gel developed in the vials of the Covid-19 vaccine made by Sinovac because they were put on ice.
FDA deputy secretary-general Surachoke Tangwiwat said the 110 vials were found at a non-hospital vaccination station in Bangkok late last week. Gel formed on the inner surface of the vials and did not disappear when they were shaken.
The problem occurred because health workers wanted to keep the vaccine cool. So they put the vials on ice. This, however, reduced the temperature of the vials that touched the ice to below 2C, he said.
He has ordered health workers to store vaccine vials carefully to ensure they were kept strictly within the instructed temperature range of 2-8C.
The vaccine in the 110 vials did not have any quality problems but was no longer suitable for injection, Dr Surachoke said. The vaccines could not be used, he said.
People who had received or would receive Sinovac vaccine can rest assured. The incident occurred at only one inoculation centre, Dr Surachoke said.
According to him, the department has examined the congealed vaccine and found that its quality remained high and comparable to other vaccines in the same batch.
"The test showed that the problem was not caused by the manufacturing procedure.
"We want to make it clear that people who received the same lot of vaccine should not panic. It is safe and efficient."
He added the problem occurred while the vaccine was being transferred to an inoculation site outside the hospital.
Dr Surachoke said guidelines have now been re-issued on how to properly store the vaccine to avoid similar problems. Using a cold gel pack is the best way to keep the vaccine at a stable temperature during transportation, he said.
Sinovac is an inactivated vaccine that must be kept at a temperature of between 2-8C. The FDA has put out guidelines to related agencies and informed them that they must strictly follow instructions to keep the vaccine at controlled temperatures. This is also recommended by the Department of Disease Control.
The congealed vaccine was found in the batch under the serial number of C202105079 and a registered number 1C3/64 (NBC), manufactured on May 10 and set to expire on Nov 9.
Around nine million doses of the Sinovac vaccine have been imported from China so far.
