This topic sort of falls between health, money and kids so wasn't sure the best place for it, but think the Education section suits it best.
Anyways, about the topic.
We recently started using OSCH for after school care and vacation care for our child. All good there and it turns out can get a rebate on the child care costs, a fair chunk in fact, for up to 50 hours of childcare a week.
Anyways, this is where that little red book, your childs health record from the UK can come in handy. To gain the rebate our child has to be up to date on the Australian Childhood Immunisation Register with all the immunisations given in Australia. The UK currently doesn't vaccinate for two of the things and so we have had to get our child vaccinated for chicken pox (varicella) and Hep B (which is a 3 part course over a few months). Neither is standard in the UK but standard here. It turns out the varicella is included with the MMR here in Australia so we either had to have another couorse of MMR or buy the varicella vaccine on its own for $59. I opted for the latter. The MMR would have been free. The Hep B was/is also free I should add. Just the single dose varicella cost us.
Now the vaccinations are up to date they have been faxed to the register to be updated onto the Aus system and we can then finalise our child care rebate. Without those vaccinations, we had to either go through the immunisation exemption for medical reasons via a GP or fill out the conscientious objection form. Neither of which I wanted to do as I don't object and there is no medical reason to not have them done (for us).
Anyways, point of this post is really to say to bring your childs little red book with you from the UK when/if you migrate. And keep them. If you ever then make use of child care in the future after arrving in Aus and can claim a rebate, it can be used to prove what vaccinations your children have had. We'd been here 15 months before I had to dig the red book out but I am very glad I had it to hand as its helped save us a heap of money on childcare. I'd have been a bit miffed if we'd had all those vaccinations done in the UK and I'd lost the proof of them all.