Phoenix Coyotes captain Shane Doan, who hasn't played since Dec. 4 due to what was an unidentified illness, has symptoms of Rocky Mountain spotted fever, general manager Don Maloney said Friday.

"Our medical team is on top of it," Maloney told Azcentral.com. "Every day he seems like he's getting a little better and a little more energy and has started to exercise a little more. We're encouraged. He's trending in a positive manner and for us. It's just going to take time."

Doan has been out of the lineup due to headache and fever, among other things. Those are symptoms of Rocky Mountain spotted fever, according to the Mayo Clinic.

Mayoclinic.com says, "Rocky Mountain spotted fever is a tick-borne bacterial disease that affects the cells in the lining of your blood vessels, making the vessels leak. This can eventually cause serious damage to internal organs, particularly your kidneys."

Maloney said Doan is taking medication and is considered week-to-week. It's not expected he'll return before the turn of the calendar year.

"It's certainly not to the point that we're worried that he'll never return," Maloney said. "But it is my understanding that it's an illness that responds to medication. Everybody's different."

Doan skated at Jobing.com Arena on Friday. The Coyotes are on a four-game road trip.

"He's disappointed but he’s in good spirits," Maloney told the team website. "The good thing is he’s feeling better every day. If he was stuck in neutral that's different, but he isn't. He's getting more energy each day and becoming more active. Hopefully that trend continues."

In his 18th season with the franchise, Doan has 12 goals and 23 points in 27 games. The Coyotes are 2-2-2 without him.

"We miss him on and off the ice," Maloney said. "He's still our leading goal-scorer, and we've scored only three goals in the last three games. So, there you go. With Shane, he can play the inside heavy game, and what I've found lately is that the majority of chances we're getting are from the outside. To me that's where we miss him more than anything on the ice.

"Off the ice, he keeps people honest and focused on the job at hand and prevents our players from getting too far ahead of themselves. We really miss his presence in these tight games where we need somebody beside the coach telling people that we've got a period here to win a game or tie a game. So, the sooner we get him back the better."