Some 40,000 patients received notices that they might have been exposed to diseases through risky injection practices, but one expert said Friday that he doesn't expect many more hepatitis cases to be linked to the Endoscopy Center of Southern Nevada.
"I believe there will be a few more, but it is not going to be a huge number," said Dr. Robert Gish, a hepatologist and medical director at California Pacific Medical Center in San Francisco.
Thousands have been tested since the health alert. To date, the Southern Nevada Health District has definitively linked six acute hepatitis C cases to the Endoscopy Center of Southern Nevada, 700 Shadow Lane, because of unsafe injection practices. A seventh case has been linked to an affiliated clinic.
The problems arose, officials say, when a syringe would be reused on an infected patient and then used to draw anesthesia from a vial intended for just one patient. The vial would be used on other patients, potentially spreading disease.
Gish, who also treats hepatitis C patients at a part-time practice in Las Vegas, said statistics indicate only 4 percent of the endoscopy center's patients would have had the disease before arriving for treatment.
In addition, the virus is very fragile and has difficulty living outside the human body, he said.
"Most of the vials were not reused, and most of the patients did not have hepatitis C," Gish said. "So we have a fragile virus, only 4 percent of the clinic's population with it and good luck that has led to the small number of identified cases."
Gish will speak today at the health district's free public forum on hepatitis C.
However, Dr. Don Havins, chief executive officer of the Clark County Medical Society, indicated it was premature to draw conclusions.
Havins said he asked health district chief Dr. Lawrence Sands "just how many positive results they (health district) have received -- if it is higher than the 4 percent. They're not at that point yet. They have no answers. We don't even have a general idea."
State epidemiologist Dr. Ihsan Azzam and Southern Nevada Health District Senior Epidemiologist Brian Labus told the state Board of Health on Friday that to understand the difficulty with linking cases to the center, it's important to differentiate between acute and chronic cases of the disease.
Labus said health officials can identify the source of the virus in acute cases, which progress rapidly. But chronic cases, which progress at a slower pace, are a different story.
"The acute ones are pretty straightforward," Labus said. "The chronic cases aren't because they could have been exposed at the clinic, or 30 years ago."
He said the agency is receiving hundreds of positive hepatitis test results a day. Prior to the hepatitis C outbreak, the health district received about 30 reports of cases a day.
Labus said the new cases, however, may never be linked to the endoscopy center.
Contact reporter Annette Wells at firstname.lastname@example.org or 702-383-0283.