Wigan coach Mike Gregory has developed a chronic bacterial infection that requires hospital treatment in the USA.
Gregory is a former Warrington and Great Britain player
Gregory will remain in charge until the Challenge Cup Final against St Helens before receiving treatment in America.
Wigan Chairman Maurice Lindsay said: "Mike has been suffering from what has turned out to be a debilitating infection for some time.
"The infection is not contagious but needs treatment and the advice is that the best treatment is in America."
Lindsay added: "Tests have revealed that the infection almost certainly started with an insect bite when Mike was on tour with the Great Britain Academy side throughout Australasia and South Africa."
Denis Betts will take charge of the team in Gregory's absence.