My only worry is that existing methods may just allow a de facto increase of the incubation period. HIV is hard to transmit--but people develop many attachments over the years. That long incubation period is what makes it deadly.
Politics is the number one hold up.
Rightists hate embryonic stem-cell research. Lefties hate animal testing.
Libertarians will allow both but would federally fund neither.
We need gov't money and researchers with no handcuffs either way.