Concerns raised as Health Ministry appears to ignore WHO warning on mixing vaccines

The public is questioning the Thai government’s proposal to combine Covid-19 vaccines from different manufacturers despite a warning from the World Health Organisation. The WHO’s chief scientist, Soumya Swaminathan, has warned against the practice, saying there is not enough information on the potential risks.

However, the Pattaya News reports that Thailand’s National Communicable Disease Committee has just approved the proposal to provide a booster dose of AstraZeneca to healthcare workers who’ve received 2 doses of Sinovac. In addition, people who have only received 1 dose of Sinovac will receive AstraZeneca as their second dose. This represents a significant deviation from standard practice to date, amid concerns over Sinovac’s efficacy against the highly-contagious Delta variant.

The variant is rapidly spreading, having been most recently found in construction workers’ camps in Bangkok, with prominent health experts saying it is set to become the dominant strain in the Kingdom. The Public Health Ministry has not responded to online comments from concerned citizens, nor has it given a statement in response to the WHO warning.

According to the Pattaya News report, if the practice of combining both AstraZeneca and Sinovac vaccines goes ahead, Thailand will become the first country in the world to adopt the procedure as official policy as opposed to a limited test. However, the public has questioned the decision, given the warning issued by the WHO.

Prominent virologist Yong Poovorawan has defended the government’s stance, pointing out that administering an inactivated vaccine like Sinovac as the first dose, followed by a viral vector vaccine like AstraZeneca as the second dose, has proven highly effective according to a recent study.

“Our recent studies found that injecting an inactivated virus vaccine, which in this case is Sinovac, as the first dose and a viral vector vaccine, which is AstraZeneca, as the second dose will boost the effectiveness of the vaccine against Delta variant without harmful side-effects.”

However, the study in question has not been peer-reviewed and was only carried out in Thailand, a fact Yong acknowledges.

“This recent study, of course, cannot be found anywhere else because most western countries do not use inactivated virus vaccines while the viral vector vaccine is not commonly used in China.”

SOURCE: The Pattaya News