LAS VEGAS – Seventy-seven more people have been diagnosed with hepatitis C that they may have contracted during treatment at a Las Vegas outpatient clinic, public health administrators said Thursday.
The 77 people are among about 400 former patients of the Endoscopy Center of Southern Nevada who tested positive for the potentially deadly virus since the outbreak was made public Feb. 27, and who provided no other risk factors during follow-up interviews, said Brian Labus, senior epidemiologist with the Southern Nevada Health District.
The 77 cases of hepatitis C combined with those confirmed earlier bring the number of cases linked to clinics run by the same group of doctors to 85.
Authorities can't say for sure how the 77 people were infected, Labus said, but they know each was treated from March 2004 to Jan. 11 this year at the clinic.
"We know they didn't have a positive test before they went to the clinic, and now they're positive," Labus said.
"They have the obvious risk factor, but we can't say for certain," Labus added. "This is as far as we can go with these cases."
Gov. Jim Gibbons said word of the additional cases "is both heartbreaking and disturbing." He added he expects the state Board of Medical Examiners to move quickly to "ensure that the physicians who played a role in these infections aren't practicing medicine while these investigations are ongoing."
Officials determined the more than 300 other patients who also tested positive and were interviewed could have contracted the virus through other means, including intravenous drug use, blood transfusions, organ transplants or kidney dialysis, receiving blood clotting agents before 1987, or sexual contact with a person with hepatitis C.
Many more people who have tested positive for hepatitis C have yet to be interviewed, Labus said.
"This is the first of many of these types of reports that will come out when we have data," Labus said. "There is no way to project how many people will test positive."
Labus and Jennifer Sizemore, spokeswoman for the Las Vegas-based health district, said local labs have reported handling about 50,000 hepatitis virus tests in the 10 weeks since officials issued a call for former patients at the clinic to get tested for hepatitis strains C, B, and HIV, the virus that causes AIDS.
Labus said no cases of hepatitis strain B or HIV have been linked to the outbreak.
Investigators found no obvious new exposure clusters like those found with the original seven acute hepatitis C cases linked to the Endoscopy Center of Southern Nevada, Labus said. They were linked by DNA testing to several treatment dates last year. The eighth case of hepatitis C was traced to a sister clinic, Desert Shadow Endoscopy Center.
The clinics were headed by doctors Dipak Desai and Eladio Carrera, whose Nevada medical licenses have been suspended pending state Board of Medical Examiners hearings.
Authorities have said at least 50,000 patients may have been exposed to unsafe injection practices by clinic staff who reused syringes and single-use vials of medication during anesthesia.
"Because the patient list we received was not complete, we cannot say for certain if all of the affected patients have been tested," Dr. Lawrence Sands, chief district health officer, said in a statement.
"The health district continues to receive a higher number of positive test results than we did before the notification in February," he said.
Sands said patients who underwent procedures at the clinic in late 2007 or early 2008 will need to be tested in coming months because it can take up to six months for a positive test result to occur.
Las Vegas police have seized medical records from the clinic, and the FBI, the Nevada state attorney general and the Clark County district attorney are involved in a criminal investigation.
The owners of the clinics have surrendered business licenses and paid $500,000 in fines.