A 46-year-old woman is in a serious condition with “significant” injuries to her thigh and torso after being attacked by a shark in the Whitsundays off the north Queensland coast.

It is believed she was swimming from a charter yacht in Cid Harbour – a popular spot for bareboat charters and private boats – near Whitsunday Island about 5pm on Wednesday when the incident occurred.

She was taken on board a larger vessel that happened to have a doctor on board.

The RACQ CQ Rescue helicopter winched the woman off the boat in Sawmill Bay and transferred her to Mackay Hospital.

She was expected to arrive at the hospital about 8pm.

It is understood a doctor was on board who helped treat the patient, with other boats also responding after hearing a mayday.

QAS Critical Care Flight Paramedic onboard Rescue Heli 412 currently responding to a reported Shark Attack approx 50kms off the Whitsunday Coast.Patient now reported to be on a boat.

— Queensland Ambulance (@QldAmbulance) September 19, 2018

The helicopter flew to Proserpine to refuel and while on the ground, extra blood will be supplied to the paramedics on board the chopper.

The Courier-Mail reports the crew was doing a beacon search in the  Bowen area when they were called to the shark attack incident.

An ambulance spokeswoman said the woman had suffered “significant leg and torso injuries”.

“The patient was swimming when she was bitten. She was pulled back on to the (yacht) with significant injuries,” the spokeswoman said.

“She was then treated by a doctor who was on the yacht before crews arrived, where she was transferred to a smaller dinghy and then winched by the helicopter.”

–ABC