– Two UnitedHealth Group Inc. units must pay $500 million in punitive damages for failing to oversee a doctor blamed for giving colonoscopy patients hepatitis C through shoddy medical practices, a Nevada jury found.

Jurors in state court deliberated more than six hours Tuesday before handing down the punitive award against Health Plan of Nevada and Sierra Health Services for turning a blind eye to Dipak Desai’s actions. The gastroenterologist has been blamed for infecting patients with hepatitis C by reusing anesthetic vials and failing to sterilize equipment.

The punitive award comes less than a week after the same jury ordered the UnitedHealth units to pay a total of $24 million in compensatory damages to Bonnie Brunson and Helen Meyer, two of Desai’s former patients who contracted hepatitis after receiving colonoscopies performed by the doctor.

The trial is the first against units of Minnetonka-based UnitedHealth over the 2007 hepatitis C outbreak. Nevada officials were forced to notify 50,000 patients they might have contracted the potentially fatal blood disease from Desai’s actions.

“The number announced today has no grounding whatsoever in reality,” Tyler Mason, a UnitedHealth spokesman, said in an e-mailed statement. “It represents fantasy damages, not punitive damages.”

Health Plan of Nevada officials said on a website created to provide information about the trial that Brunson’s and Meyer’s cases were “driven only by attorney greed.”

Nevada juries already have handed down multimillion-dollar punitive awards against Teva Pharmaceutical Industries Ltd., maker of the anesthetic Propofol that Desai reused in his procedures. Three juries awarded colonoscopy patients more than $750 million in punitive damages over the drugmaker’s decision to sell the anesthetic in oversized vials that invited such reuse.

Teva, based in Petach Tikva, Israel, agreed last year to pay $250 million to settle more than 80 lawsuits over Propofol sales.

Desai, 62, and two nurse anesthetists face second-degree murder charges over the death of a colonoscopy patient.

The former doctor also faces federal fraud charges. Desai is set to go to trial April 22 on charges filed by state prosecutors.

Last week, jurors found the UnitedHealth units were negligent for failing to properly monitor Desai’s performance and “acted in bad faith.” That left the companies open to a punitive-damage award.