NASHVILLE (AP) — A cluster of meningitis cases that left two people dead in Nashville is under investigation by the Tennessee Department of Health and the Centers for Disease Control and Prevention.

According to the Department of Health, 11 patients who had lumbar epidural steroid injections at Nashville's Saint Thomas Outpatient Neurosurgery Center have come down with the disease.

CDC spokesman Curtis Allen said there also has been a case in North Carolina in someone who received the same type of injection. He declined to identify the facility where that injection was administered.

Allen said the type of meningitis is fungal and is not transmitted from person to person. The cause for the cluster is not yet known.

Although the 12 patients who came down with meningitis all received the pain injections, Allen said they could have other things in common as well and it is too early to single out the source of the infections.

Meningitis is a general term for an infection or inflammation of the lining of the brain and the central nervous system.

According to the Tennessee Health Department, the approximately 730 patients who received the injections in Nashville between July 30 and Sept. 20 of this year have been notified of the outbreak.

The Saint Thomas Outpatient Neurosurgery Center closed voluntarily on Sept. 20 with plans to remain closed "until the source of the adverse reactions is known," according to a news release from the center.

"We reported the cases involving meningeal symptoms to the TDH and have been working closely with the TDH and the CDC in their research," the statement reads.

The CDC's Allen said the agency has sent two people to Tennessee to assist with the investigation. It also is coordinating with other state health departments to determine whether there are additional cases. And it is providing guidance to the clinicians who are treating the infected patients.

The CDC is evaluating the products and medications used at the clinic, including the epidural injections, but has not yet found sufficient evidence to identify the cause or source of the outbreak, Allen said.