What do I do if I had the first AZ jab and I don't want to get the second one? I assume you can't mix and match? If I got the first jab and didn't have nasty side effects does that mean I won't get clots from the second one?
Of course you can mix n match. It is almost completely untested, but hell taking two doses of any of the same coronavirus vaccines are not exactly thoroughly tested either. Alternatively just don't bother with dose 2.
Maybe mix n match vaccine has been tested more than we think? Emergent Biosolutions in Baltimore have been busy doing their own mix and match lucky dip contract vaccine manufacture, randomly contaminating J&J with AZ virus so maybe this combo has already been widely tested?
The reason for dose 2 is to get the antibody titers in vaccinated individuals above those seen in recovered naturally infected people also (during the trials it was handy and used to disappear those people in the vaccine arm who got corona after the first dose making the vaccine look more efficacious). Higher antibody levels than recovered people is an important marketing tool so the vaccine sellers can claim the vaccine gives 'better' immunity than natural infection.
When this shakes out the first dose of vaccine is likely to have done most of the work. However all the currently claimed numbers for effectiveness and efficacy are implausible.
Perhaps it does but only for antibodies against spike and it is a huge mistake to say higher circulating antibody levels correlate with higher immunity and higher protection. In this situation the obsession with quantity and quantifiable numbers is obscuring quality.
So far clots appear to have been from dose 1. Obviously dose 2 is not given to people who had detected clots from dose 1. If the mechanism is what I think it is the first dose is more dangerous than the second.
Relatively few people have had 2 doses of AZ.
Weak post deployment surveillance and clear burying of bad news by the medical profession and media clouds the situation.
no guarantee dose 2 won't cause problems but you are in Australia/NZ so why does being vaccinated right now matter at all? you can be pragmatic and can afford to wait and see what happens to the other lab rats at zero cost.