Federal health officials have identified 137 cases of fungal meningitis in 10 states, with 12 deaths. Officials stress that the investigation is ongoing, but they have linked the outbreak to contaminated steroids compounded and distributed by a single company, New England Compounding Center in Framingham, Massachusetts. Most of the infections are linked to spinal epidural injections. Only one clinic in Georgia is involved: the Forsyth Street Ambulatory Surgery Center in Macon. It has identified 184 patients who may have been exposed to the contaminated drug. All have been contacted, and none has yet developed meningitis.

The emergency operations center is bustling at the Centers for Disease Control in Atlanta, where scientists recently learned that the fungus linked to a multistate outbreak of lethal meningitis is actually two fungi.

That means the CDC must revise the treatment protocol and advise doctors in the 23 states with potential victims to switch to a broader spectrum of drugs.

“We’re still discovering what we’re up against,” said Dr. Benjamin Park, who is leading the CDC investigation.

The scene recalls images of NASA’s mission control center. Workers sitting at long long tables look up at an array of large screens with maps pinpointing confirmed cases and deaths.

Dr. John Jernigan, a CDC epidemiologist, has assembled a team of the world’s leading experts in fungal infections. They spent Tuesday clarifying which patients are in the gravest danger. Many of those afflicted with the disease are elderly, he said.

As of Wednesday afternoon, there were 137 cases and 12 deaths across 10 states. Tuesday’s tally was 119 cases and 11 deaths.

“This is a rapidly evolving situation,” Jernigan said.

This isn’t your garden variety meningitis. Fungal meningitis is rare; there isn’t much scientific research or treatment guidance to fall back on.

Health officials have traced the outbreak to a steroid used in pain injections. It was formulated by one company in Massachusetts and delivered to 75 clinics in 23 states nationwide.

That includes just one facility in Georgia, in Macon. That clinic, the Forsyth Street Ambulatory Surgery Center, has identified and alerted 184 patients who may have been infected. As of yet, none of them has been diagnosed with meningitis.

The CDC complex off Clifton Road is coordinating the national effort to make sure affected patients get timely treatment that can save their lives. The emergency operations center has marshaled over 100 workers to that end.

They are gathering information from health agencies in the affected states, honing treatment options and helping local health workers contact the 13,000 people who may have been infected. In the CDC’s labs, workers are extracting DNA from samples of spinal fluid and running tests to determine who is infected.

Meningitis attacks the spinal cord and brain, potentially causing brain damage, stroke and even death.

Despite the severity of the disease, Park said there’s some good news thus far: The great majority of potential victims have been contacted, and most of those who have been tested were not infected. Also, this form of meningitis is not contagious.

The bad news is that new cases are emerging virtually every day. Patients may not feel symptoms for up to a month after the steroid injections, which officials believe were administered between May and September. So more cases may show up in coming weeks.

“We expect to hear about more deaths,” Park said.

On Tuesday, Carla Mercado had set aside her regular research into heart disease. She was helping contact potential victims in Maryland, asking questions from a prepared script: Have you had fever? A stiff neck? Has your speech been slurred? Do you have swelling at the site of the injection?

When she breaks the news that the steroid shot the patient received to alleviate chronic pain may now be making them sick, some people get real quiet.

“They listen and they want more information,” she said.

The state’s Department of Public Health is also reaching out to Georgians who received the potentially contaminated shots, asking them about symptoms and recommending testings when necessary, said Dr. Patrick O’Neal, the agency’s director of health protection.

At the clinic in Macon, Dr. Frank Kelly said all of the 184 people who received the potentially contaminated medication have been contacted. Eight of the patients have possible symptoms, mostly headaches, which could be caused by other maladies. Those people have been advised to get tested. Two people have undergone spinal taps for further testing; both samples came back negative.

“We’ve been working night and day to contact our patients,” Kelly said.

The center performs about 10 epidural spinal injections a week. Kelly said he has ordered drugs from the implicated company, the New England Compounding Center, since 2009, with no problems.

The CDC, the nation’s chief disease-fighting agency, ramped up its investigation last week when the meningitis cases, first isolated to Tennessee, emerged in other states.

Since then, boxes containing samples of spinal fluid from various states have been piling up at the CDC lab. That's where researchers discovered that the original suspect fungus, Aspergillus fumigatus, was accompanied by a second organism, Exserohilum rostratum.

The CDC is not involved in regulating drug manufacturers; that’s the role of the federal Food and Drug Administration. The FDA is performing a separate investigation into what went wrong at the Massachusetts company, which has ceased production and recalled the potentially contaminated steroids.

The episode has led to widespread calls for congressional investigations and tighter controls on pharmacies such as the one in Massachusetts that mix their own drug compounds.

Meanwhile, the CDC is racing against time in a situation that continues to evolve. For instance, the agency just recently learned that some people may have received the contaminated steroid shots in their joints, not their spines. Now it’s informing officials in the affected states that, in addition to meningitis, the possible repercussions may include septic arthritis, a painful swelling of the joints.

“Time is of the essence,” said Park of the CDC. “We know if patients with infection are identified soon and put on appropriate antifungal therapy, lives may be saved.”