* McIlroy "unwilling to take the risk" * Joins growing list of golfers pulling out of Rio Games * "It does strike me as being a bit extreme" says medical expert (Adds IGF statement) By Adrian Warner LONDON, June 22 (Reuters) - Northern Ireland's four-times major winner Rory McIlroy has decided to pull out of the historic golf tournament at the Rio Olympic Games in August because of health fears over the Zika virus. "After speaking with those closest to me, I've come to realise that my health and my family's health comes before anything else," the world number four said in a statement on Wednesday. "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." The International Golf Federation (IGF) said it was disappointed with McIlroy's decision. More...