Rio authorities announced how to prevent Zika in upcoming Olympics

Brazil has the largest-known outbreak of the virus which has been linked to a spike in birth defects in new-born babies whose mothers were bitten by the mosquito during pregnancy. The US, Canada and EU health agencies have issued warnings saying pregnant women should avoid travelling to Brazil and other countries in the Americas which have registered cases of Zika. The Brazilian authorities have announced plans to prevent the spread of the Zika virus during the Rio de Janeiro Olympic Games later this year.
Inspections of Olympic facilities will begin four months before the Games to get rid of mosquito breeding grounds.
Daily sweeps will also take place during the Games. But fumigation would only be an option on a case-by-case basis because of concerns for the health of the athletes and visitors.

The Brazilian health ministry says it is also banking on the fact that the Games are taking place in the cooler, drier month of August when mosquitoes are far less evident and there are considerably fewer cases of mosquito-borne viruses.