Sydney - The mystery illness which forced late changes to the Brumbies' line-up against the Highlanders last weekend was confirmed on Wednesday as mumps.
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Several players and staff from the Canberra-based Super Rugby team have been stricken with the illness, ruling them out for the trip to Hamilton ahead of the Chiefs clash (Saturday, February 22 at 08:05 SA time), according to Rugby Australia.
Darcy Swain and Irae Simone were swapped out of the squad on game day last Saturday due to an illness.
Further tests revealed that the virus had infected some staff and players.
"Any sort of virus you've got to be really careful in our environment because you spend so much time together," Brumbies coach Dan McKellar said after the match on Saturday.
Local health bodies and Super Rugby's governing body had been called into manage the outbreak, with only healthy players receiving the all clear to travel.
Rugby Australia said all teams in the competition had been contacted and no further cases have been detected.