Zika, Ebola, MERS coronavirus and yellow fever have shown that the world is not prepared to deal with the rapid spread of infectious diseases, the head of the World Health Organization (WHO) warned on Monday. Margaret Chan opened the 69th World Health Assembly with remarks that underscored the many gaps that exist as an unprecedented series of global health challenges continue to evolve.

“Let me give you a stern warning. What we are seeing now looks more and more like a dramatic resurgence of the threat from emerging and re-emerging infectious diseases,” said Chan in a speech delivered to open the event. “The world is not prepared to cope.”

Late last week,