host: alexandra phelan.t: on the liability of the olympic committee, the olympic committee said if individual competitors do not wish to go. i'm not a lawyer with transnational law around the olympic committee, but my assessment is that there would be communities in place -- immunities in place for them provided they are communicating with athletes. in terms of cruise ships, the warnings have been two women traveling to those areas, pregnant women in particular or women who may get pregnant. it is a much narrower series of warnings. in healthy people and the majority who do get infection, it is not serious. host: can you talk about who is leading the response and what the role is of the c.d.c. versus the w.h.o.? guest: the w.h.o., world health organization, is the global united nations agency tasked with feeling of matters of global health, including public health emergencies like this. the w.h.o. will provide technical advice to countries about what the zika virus involves, all the clavicle -- clinical side