Rory McIlroy, ranked No. 4 in the overall world standings, has decided not to compete in the Olympic Games because of concerns over the Zika virus.
McIlroy said in a statement, "Even though the risk of infection from the Zika virus is considered low, it is a risk nonetheless and a risk I am unwilling to take."
McIlroy's decision is bad news for the sport of golf, which is making its return to the Olympics after a 112-year absence, and for Ireland, the country for which McIlroy had pledged to play.
The Zika virus is spread through mosquito bites and is known to cause birth defects. Brazil has been facing a Zika outbreak since May 2015.
It's unclear how risky it is to visit Rio de Janeiro this August. More than 100 distinguished physicians and scientists have called for the Olympic Games to be moved.
Just four months ago, the World Health Organization said Zika was "spreading explosively." But the organization has also maintained the risk for the Olympics is very low. A Brazilian official cited a University of Cambridge study that found of the 500,000 foreign tourists traveling to the games, one will get infected.
McIlroy may have company. Rickie Fowler, the world's No. 6-ranked golfer, is reportedly also questioning if he'll play in the games.
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