I know we don't give either of these vaccines in the UK but this is quite a big story which highlights the worrying issue of vaccine contamination.
This happened before with a simian virus in polio vaccines.
Don't know about anyone else but when I gaily trotted along to my doctor to have DD1 vaccinated it didn't occur to me that this sort of thing could happen. I naively assumed that vaccines contained a tiny bit of virus or bacteria and nothing else.
Anyway here is Barbara Loe Fisher (campaigner for vaccine safety and the right to informed consent in the US) on the subject.
vaccineawakening.blogspot.com/
I wonder what Dr Offit has to say about this.