If it is what I think it is, I saw a warning about it a while back.PDE?
It's something like 'protein/anti-body dependent enhancement'.
Antibody-dependent enhancement - Wikipedia
en.m.wikipedia.org
Basically the vaccine has the 'opposite' of the intended effect, and makes the regular virus's symptoms worse.
Supposedly rare, but has been noted in other types of vaccines, and seems to mostly happen in people who are vaccinated without running through the regular infection first.
Not sure how legit it is related to the Wu Flu vaccines, but I've heard rumblings about this concern for a few months now on parts of Twitter.