Professor Allen Cheng (Image: AAP/James Ross)

For much of her long career, consumer health advocate Debra Petrys has worked behind the scenes but this week she has emerged, under pressure, to defend her role in the fateful decision taken by the Australian Technical Advisory Group on Immunisation (ATAGI) in April to recommend Pfizer over AstraZeneca as the preferred vaccine for those 50 and under.

"The decision weighed heavily on me," Petrys told Crikey. "Did I know it would create vaccine hesitancy? Yes I did. I still think it was the right decision."

She said this even as Australia's vaccine rollout falters badly in no small measure due to the trashing of the AstraZeneca brand.