What about Tdap (白百破-白喉,百日咳和破傷風)乙肝 HBV,甲肝HAV 和流感 Flu? I am not sure if they are reqiured or recommended? If required, I will have them get the shots in China which are much cheaper.
-The Dr. in US know what items are needed. I do not suggest your parents do it in China because you do not know whether the US Dr. will accept the results or not. Also, the fee is not expensive that much in US than that in China.