The authorities said there was no risk to athletes and spectators - except pregnant women - at the August event.

The World Health Organization declared the Zika virus a global public health emergency on Monday (01), following a recommendation by a committee of independent experts.

"I am now declaring that the recent cluster of microcephaly and other neurological abnormalities reported in Latin America following a similar cluster in French Polynesia in 2014 constitutes a public health emergency of international concern," WHO Director-General Margaret Chan said on Monday.

The infection has been linked to cases of microcephaly, in which babies are born with underdeveloped brains.

Experts are worried that the mosquito-borne virus in Latin America is spreading far and fast, with devastating consequences.

-BBC