NEW YORK (AP) — Is Ebola the world’s worst infectious disease threat since AIDS?

Comparisons between the two deadly diseases have surfaced in the last few months as the Ebola outbreak has escalated.

Both emerged from Africa and erupted into an international health crisis. And both have been a shocking reminder that mankind’s battle against infectious diseases can take a sudden, terrible turn for the worse.

The head of the Centers for Disease Control and Prevention, Dr. Tom Frieden, says the only thing like Ebola he’s seen in his three decades in public health has been the AIDs epidemic.

But Dr. Anthony Fauci says Ebola is not expected to be in the same league as AIDS in terms of infections and deaths. Fauci is director of the National Institute of Allergy and Infectious Diseases.