Jolted by the possibility of a syphilis outbreak among its ranks, a Los Angeles-based trade group that represents the adult film industry announced a nationwide moratorium on X-rated productions while more than 1,000 porn performers are tested.

The Free Speech Coalition issued the call on its website after reporting that one performer tested positive for syphilis, a sexually transmitted disease, and had begun notifying sexual partners of that information.

The moratorium was announced Saturday, a day after Los Angeles County’s Public Health Department said it was investigating a cluster of possible syphilis cases within the porn industry. The agency said it had received reports of at least five cases involving adult performers within a week.

The head of the coalition would not agree to an interview, but on its website, the group said that it was calling for a temporary halt to film shoots while the “entire population” of performers is examined by doctors.

“A determination will be made by the doctors on the appropriate time to lift the moratorium as more information is revealed,” the group said.

Michael Weinstein, president of the AIDS Healthcare Foundation, said Monday the developments show that adult film companies are incapable of policing themselves. His group said the syphilis incident would be used as part of the campaign for Measure B, a proposal on the Nov. 6 countywide ballot mandating the use condoms during professional X-rated shoots. And it accused adult film productions of being “bad corporate citizens,” saying that no other business would tolerate transmission of any diseases, sexual or otherwise.

“We don’t settle for that in food preparation. We don’t settle for that in factories,” said Tom Myers, general counsel for the group. “I can’t think of any other [workplace] where there’s an acceptable level of transmissible diseases as a normal course of business “

The number of syphilis cases in California jumped 18% from 2010 to 2011, according to state health officials. If left untreated, the bacterial disease can cause permanent damage to the heart, brain, and other organs. In Los Angeles, officials are trying to map out a strategy for inspecting adult film shoots, part of an ordinance passed by the City Council this year.

City officials are hoping voters will approve Measure B, which would allow the city to rely on the county’s health department to conduct spot inspections.

Weinstein said city officials had overcome the “ick factor” surrounding the condom issue and are making progress developing an enforcement strategy. But Diane Duke, executive director of the Free Speech Coalition, criticized them for devoting taxpayer resources on the matter.

“In a time when multiple California cities are going bankrupt, L.A. itself has a significant budgetary problem, and city services are being cut drastically, I find it unconscionable that the city would create a new bureaucracy to monitor condoms on adult film performers,” she said in a statement.

Duke also said in an email that Measure B would ultimately endanger porn performers by pushing adult film shoots “underground” or out of the county. She also accused Weinstein’s group of waging “a relentless attack on the adult industry” since 2009.

Weinstein, in turn, accused the adult film industry of doing too little to stop the spread of sexually transmitted diseases. He said producers make performers pay for their own testing and require that syphilis screening be done only twice a year.

“If we look at the fact that syphilis has up to a 90-day incubation period and the fact that the industry only tests these employees every six months … a person could go as long as nine months without being diagnosed” with syphilis, he said.

david.zahniser@latimes.com