MELBOURNE defender Christian Salem is still at least a month away from returning to play but he received some positive news about his health during the week.

Salem has not played since last running out for the Casey Scorpions against Box Hill on May 21, after which his thyroid problem resurfaced and he was listed as an indefinite prospect on the Demons' injury list.

But in good news for the Demons, elite performance manager Dave Misson said Salem, pick No.9 in the 2013 NAB AFL Draft, is on the road to recovery.

"Christian Salem got some good medical results in the last couple of days so we're hoping he'll only be three or four weeks after the bye," Misson told the club's website.

Salem's return to the field relied on a series of tests to check whether his blood levels had returned to a healthy figure.

The young Demon will also be placed on the medication he took when the illness first flared in 2014, causing him to lose six kilograms prior to that year's Christmas break.

The thyroid is a gland in the neck that helps control the body's heart rate, blood pressure, body temperature and weight, and the Demons were worried after Salem looked lethargic in the game against Box Hill.

Salem, who has played seven matches in the seniors this season, has been on the training track in recent weeks but has only been able to train lightly.

In further good news on the injury front for the Demons, Heritier Lumumba (concussion), Sam Weideman (hip flexor), Lynden Dunn (hamstring) and Cameron Pedersen (illness) will all be available to play following Melbourne's bye.

Young forward Jay Kennedy-Harris, who injured his hamstring for the third time this season after tweaking it at training a fortnight ago, remains four weeks away from a return.

Rookie Joel Smith (groin) faces a similar timeframe for his recovery.

Melbourne's next game comes in round 15 when it takes on Adelaide at the MCG on July 3.