Los Angeles, CALIFORNIA - In the halls of the VA West Los Angeles Medical Center, what may look like decorative lights are really flytraps known as flylights.  CBS Los Angeles reports that more than 200 traps had to be installed because of an outbreak of flies that's gone on for years.

Behind some of the lights, CBS Los Angeles' hidden camera found what appeared to be insects caught on glueboards.

One picture shows the traps are even inside the operating rooms.  And for good reason.

"The flies have flown into the operating room at times, requiring cancellation of surgeries," said Dr. Christian Head, associate director and chief of staff for quality assurance at the West LA facility.

"I don't believe there's any hospital in this country that would find it acceptable to have flies on a routine basis," said Head, who is also a head and neck surgeon at the hospital.

CBS Los Angeles obtained emails and memos showing the infestation goes back as far as November 2016.

One titled "Phorid Flies in the Operating Rooms" said, "When spot treatments became ineffective, the ORs closed for terminal extermination and cleaning."

CBS Los Angeles learned the operating rooms at the facility were closed a total of 22 days from November 2016 through February of this year because of fly infestations that could jeopardize surgeries.

"They're predators, parasites, scavengers," said Brian Brown, curator of entomology at the Natural History Museum in downtown LA, where over a million types of dead insects are studied.

The phorid flies are so tiny they're kept on pins.

Under a microscope, one can see how they can carry bacteria and endanger the sterile environment of an operating room.

"They're attracted to open wounds for the fluids that they need to sustain themselves and also to keep from drying out," Brown said.

"They can transmit the bacteria?" CBS Los Angeles investigative reporter David Goldstein asked.

"Correct," Brown said.  "They could also lay eggs on the open wounds."

The Department of Veterans Affairs said 83 surgeries had to be postponed from November 2016 through February of this year because of the fly infestation, leaving some of America's veterans having to wait even longer to get the care they need.

"When a surgery is scheduled, they may have been waiting four to five weeks or sometimes longer, and to tell them that the case was canceled ... it's a big deal," Head said.

Eric Hannel, who was an investigator for the House Veterans Affairs Committee, said, "The fact that VA has waited for more than two years to properly address this, I think, underscores a leadership failure at the highest levels."

Head said he and others reported the fly problem, but he said instead of addressing it, the VA suspended one doctor, and he said they retaliated against him as well.

"I think there's a culture that exists within the Veterans Administration that punishes people who are willing to be honest and come forward," he said.

In a statement, the VA said, "We found zero evidence of patient harm" but closed the operating rooms "out of an abundance of caution."

The statement also said that "currently all operation rooms are open," and the VA is "working closely with national subject matter experts to ensure this does not occur again."

But the flytraps are still in place, and doctors who CBS Los Angeles spoke with said they have no doubt the flies will remain a problem affecting the care of veterans in West LA.

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