I think between the 12 year time gap, her 'whims' of discovering a vaccine could have interfered with the global powers decisions on handling the outbreak. It is possible that, maybe, the higher ups of the government (if any) was deciding to eradicate ALL infected. She, however, probably insisted on making a vaccine that could grant immunity to non infected and maybe even cure the infected (revival drug?). Thats probably why she is both enemy and hope of humanity, because she is (maybe) delaying the eradication of the virus by not letting the infected get removed, and yet at the same time developing a cure-all drug that could save everyone.