As many as 110 bottles of Sinovac COVID-19 vaccine have been found to contain a lump of transparent gel, which did not go away after being shaken. It is believed to be caused by the vaccine being stored at a temperature too low that recommended, according to Thailand’s Food and Drug Administration (TFDA).

The bottles in question were found at one vaccination sites and have been returned to the TFDA, which has called for the suspension of the administration of any bottles of Sinovac’s CoronaVac vaccine which are found to contain lumps and notification of such discoveries.

No one has been administered with the gel-like Sinovac vaccine, confirmed TFDA Deputy Secretary-General Surachok Tangwiwat today (Tuesday).

The gel is likely formed either because the vaccine is too cold, or its pH level has changed, said Dr. Surachok.

“The lumpy vaccine is not dangerous, but its efficacy would be reduced. There is no need for people getting this vaccine batch to be alarmed as the problematic ones were not in use,” he said.

The TFDA has sent a letter, dated yesterday, informing all provincial health offices and hospitals across the country, administering Sinovac vaccine, to beware of the C202105079 batch, produced on May 10^th and which expires on November 9^th, and that it may contain a gel-like substance.

The recommended storage temperature for CoronaVac is 2-8^oC, according to the TFDA which has recommended storage of the Sinovac vaccine in the middle section of the refrigerator, away from the evaporator fan.

10.5 million doses of the Sinovac vaccine have been delivered from China to Thailand to date, with millions more expected to be received this and next year. It remains the most widely administered vaccine in the country.

A total of 4.7 million doses of the AstraZeneca vaccine have been delivered so far, as well as 1 million doses of Sinopharm from China.