KUALA LUMPUR, June 30 ― National Covid-19 Immunisation Programme coordinating minister Khairy Jamaluddin assured AstraZeneca vaccine recipients today they will get the same for their second dose, following claims that different vaccines could be mixed to try and boost efficacy.

Khairy said this amid rumours that those who received the AstraZeneca vaccine during the opt-in programme would be receiving the Pfizer-BioNtech vaccine for their second dose.

"For the AstraZeneca vaccine, the second dose will be AstraZeneca.

"Although the expert technical group have presented to the Covid-19 Vaccine Supply Access Guarantee Special Committee (JKJAV) on heterologous vaccination that is mixing vaccines, we are still studying and do think its still inconclusive for us to make a decision to mix vaccines here in Malaysia.

"We will continue to study that and once a conclusive decision can be made, then we will announce. For now you will be given the same second dose as your first dose,” he said during the weekly Covid-19 Immunisation Task Force press briefing here.

This after reports of early data from a German trial involving a small test group of only 26 young patients suggesting a combination of AstraZeneca and Pfizer vaccine doses may trigger immune responses up to four times stronger than if administered two doses of the same vaccine.

The test showed the heterologous vaccination methods to be more effective in neutralising antibodies to protect the recipients from new Covid-19 variants such as the Alpha and Beta variants.

It was also reported that repeated doses of either vaccine showed a tendency of it becoming less effective over time, or induced stronger side effects with repeated doses.