The Food and Drug Administration reported on Tuesday that gel developed in 110 vials of the Covid-19 vaccine made by Sinovac because they were put in 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 developed 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 in ice. This, however, reduced the temperature of the vials that touched the ice to below than 2°C, he said.
He had ordered health workers to store vaccine vials carefully to ensure they were kept within the instructed temperature range of 2-8°C.
The vaccine in the 110 vials did not have any quality problem but was not suitable for injection, Dr Surachoke said. The vaccine was not used, he said.
People who had received or would receive Sinovac vaccine could rest assured. The incident occurred at only one inoculation centre, Dr Surachoke said.
