Israel Study: Our results show that there is an increased incidence of VOC B.1.351 (SA variant) in vaccine breakthrough infections in fully vaccinated individuals with BNT162b2, (Pfizer) and increased incidence of VOC B.1.1.7 (UK) in partially vaccinated individuals.

(I)n vitro neutralization assays that have shown a large reduction in neutralization against B.1.351

So it's not just AZ that fails against the SA variant.

(A) significantly higher proportion of B.1.351 was observed in FE (vaccinated) cases vs. unvaccinated controls.

The study does say it was a small sample size and the results can't be taken as definitive.

But then you have to ask, where are the big sample-size studies that we can take as definitive? Why are they not being published?