There is confidence in the Group 4 vaccination rollout.

People aged 60 plus can now book an appointment to get jabbed, despite many in Group 3 who are yet to receive theirs.

Invitations open to those over 45 from mid to late August, and mid to late September for people 35 plus.

Otago University infectious diseases expert David Murdoch told Mike Hosking he's optimistic health officials will be able to rise to the task.

“This is always going to be a complex programme; there are always things that can be done better. The key thing is that we’re working on it.”

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