the MIA IS an incentive payment. there are parents out there that make the conscious decision to not vaccinate (as is the case with Leash contemplating the CP vax) - but there are others who simply "forget" that immunisations are due at a certain time. by having an incentive to get them done and on time, this has decreased massively. the MIA used to be paid in one lump sum between 18 and 24 months - but the same thing started happening with the later immunisations - so it was split in two - with the other half paid between 4 and 5 when those vax have happened

the CP vax isn't compulsory for the earliest installment of MIA as it is not NATIONALLY scheduled. the federal government can't discriminate against someone in queensland (for instance) and not pay them the MIA for not having the CP as scheduled, when other states don't have that vax on the schedule and get the payment (hope that makes sense)

the childcare side of things is as Loula said - if your child is not up to date with their immunisations, you will be contacted and your child may not be able to attend care if their is an outbreak of something they are not immunised again. child care benefit payments are again based on your child being up to date with immunisations (incentive wise) - if your child is behind in immunisations by longer than a certain time, you get a letter reminding you to get these done or your child will not receive child care benefit (or child care rebate) - meaning you have to pay full fees. if you don't arrange to have imms done, you do end up paying full fees - and child care benefit will not be back dated to cover any time between when max rate fees start and when you get your child immunised. if you are unsure about whether to have your child immunised, i would suggest speaking to your GP/care provider and getting the conscientious objection form lodged