INDIANAPOLIS – At the epicenter of the largest outbreak of HIV in state history, one of the first barriers that health officials face is finding out who’s infected.

Testing for the virus that causes AIDS has emerged as a critical issue in Scott County. Local doctors say residents who need to be tested are afraid of the stigma associated with the disease, or of finding out the results.

Even if they are so inclined, those most in danger of contracting the virus find their options for testing are limited.

Health officials have confirmed 55 cases of HIV in Scott County since December. The number is expected to soon reach triple digits.

Dr. Shane Avery, a local physician, describes the outbreak that has spread rapidly among intravenous drug users and commercial sex workers since late December as a “raging fire spreading house to house.”

Public health experts have described it as the worst single outbreak of HIV in Indiana history.

But its spread is obscured by a lack of testing.

Of Indiana’s 92 counties, only 23 have centers where people enrolled in Medicaid or who have no insurance can be tested for HIV at little or no cost.

Scott County’s health department doesn’t offer state-funded tests for HIV.

Avery said one of his patients drove 60 miles round-trip last week to the nearest facility.

Travel wasn’t the only problem. As the patient sat in a crowded waiting room, her name was called. So was the reason for her visit, Avery said, in apparent violation of federal health privacy rules.

Avery said he worries that word of that encounter will spread and make people who’ve been exposed to the virus even more reluctant to be tested.

“The stigma of HIV is huge,” he said. “And in a small town, it’s even worse. Once you have it, you’re afraid that everybody knows it.”

Avery and other health officials say they fear these problems could confront any rural community with an IV drug problem and few public health resources.

Their problem is spreading fast. Last week, the county sheriff reported 10 inmates in his jail had tested positive for HIV. Other inmates who may have used contaminated needles refuse to be tested.

Avery said he had just one patient diagnosed with HIV in his 16 years of practice in Scott County – a poor, rural community with about 24,000 residents. This year alone, three of his patients have tested HIV-positive.

The lack of resources in rural communities reflects a larger issue, said Rep. Tim Brown, R-Crawfordsville, an emergency room physician and former chairman of the House Public Health Committee.

“It’s not a testing problem, it’s a cost problem,” said Brown. “County health departments have been coming to us for years, telling us they don’t have enough money.”

Each HIV test costs providers about $70 to administer the screening and verify the results. Many rural health departments don’t have the financial resources to offer the test for free.

Brown said state funding for county health departments hasn’t increased since the late 1990s. Larger counties with bigger budgets are forced to pick up the extra costs, he said.

Access to testing centers isn’t the only problem that worries public health experts trying to contain the HIV outbreak.

A 2011 study of HIV-testing centers, funded by the State Department of Health, uncovered problems with confidentiality and low confidence in the system.

In the study, researchers with the Rural Center for AIDS/STD Prevention at Indiana University sent people undercover into 33 testing centers, posing as potential HIV patients.

In 20 percent of their visits, HIV test kits weren’t available. In 42 percent of the visits, patients reported their confidential information was compromised by staff.

Almost half of the undercover investigators said they were so poorly treated, they’d never return to the centers.

Beth Meyerson, co-director of the Rural Center for AIDS/STD Prevention, who oversaw the study, said the results indicate an inadequate public health system that’s unprepared for the current HIV outbreak.

“Yes, we’ve got a raging fire,” said Meyerson, echoing Avery, “but we’ve had the heat underground for years.”

On Wednesday, Meyerson and Avery are expected to testify at a House Public Health Committee hearing on the HIV outbreak and a proposal to allow Scott County officials to launch an emergency needle-exchange program to stem the spread of the virus.

Rep. Ed Clere, R-New Albany, the committee’s chairman, said he expects the hearing to reveal larger public health issues in rural Indiana.

“The current crisis is bringing attention to the lack of HIV/AIDS infrastructure in Indiana,” he said. “There are many underserved areas and many needs, including better access to testing.”