@Marco_Piani If you're not sure, you cast a wide net. As I recall, trials were planned on short notice in particular local areas that were having large outbreaks. That could have been done in Australia when large outbreaks happened if anyone wanted to. Wasn't a need.
@Marco_Piani如果你不确定，你就撒网了。我记得，试验计划是在短时间内进行的，特别是在发生大规模疫情的局部地区。如果有人愿意的话，当大规模疫情发生时，这本可以在澳大利亚实现。不需要。