A team at Chulalongkorn University is studying whether a combination of vaccines can increase Covid immunity.

Researchers at the university’s Centre of Excellence in Clinical Virology are looking into whether Covid-19 shots from different vaccine makers can better boost immunity and maximise safeguards against infection from the rapidly spreading Delta (Indian) variant.

Study results are expected in a few months, according to the head of the centre, Dr Yong Poovorawan.

His research team is working with partners to study administering the vaccine using a combination of Sinovac and AstraZeneca.

The study might show that combining vaccines could lift immunity and guard against infections more effectively than relying on a single brand.

According to Dr Yong, the study involves using Sinovac vaccine as the first dose, followed by the AstraZeneca vaccine as a second dose administered four weeks later.

"In laboratory tests, we have seen very satisfying results. But we are still very concerned about side-effects," he said.

The results of the study will be forwarded to the government, he added.

Dr Yong also stressed the need to slow rapid transmission of the Delta strain of the virus. He said some people have shown low immunity after receiving two shots of either Sinovac or AstraZeneca and that they could benefit from a third shot which, if administered at a proper time, might spur immunity tenfold.

Dr Yong insisted it would be unnecessary for people to go for a test to gauge their levels of immunity after receiving vaccine shots. Moreover, different hospitals employ different methods to run such tests and this could put accuracy in doubt.

On combining vaccines, the professor said the practice is done in many European countries. However, he noted that Thailand is different because the vaccines made available locally are either inactivated or viral vector types. Combining them may not be as easy as in Europe.