NASHVILLE (AP) - The state's death toll from an outbreak of rare fungal meningitis has risen to six, Tennessee Department of Health officials said Tuesday.

Health commissioner Dr. John Dreyzhener said the number of cases in the state has increased by four and stands at 39. State officials would not release many details about the additional deaths, but said that they occurred earlier in September and October.

The cases all stem from epidural steroid injections for back pain. Evidence points to contaminated medicine that investigators say was made by New England Compounding Center, a specialty pharmacy in Massachusetts.

About 17,700 single-dose vials of the steroid sent to 23 states have been recalled. Inspectors found at least one sealed vial contaminated with fungus, and tests were being done on other vials as the cause of the rare disease.

The outbreak involves 10 states, but Tennessee so far has reported the greatest number of cases. The Centers for Disease Control and Prevention said Tuesday that there have been 119 infections and 11 deaths across the nation.

Dreyzhner said that the ongoing investigation has found that the main pathogen found in the patients in Tennessee is a fungus called exserohilum, which is a common mold or fungus found in the environment, but that is exceptionally rare as a human pathogen.

But he noted that the anti-fungal treatment being used is effective. This form of meningitis is not contagious.

The state also expanded the possible incubation period for patients who have received injections from the potentially contaminated lot. Previously, the state said people could start to show symptoms between two and 28 days after the injections.

"Based on the analysis of additional case studies, the more accurate range appears to be six to 42 days for our patients in Tennessee," he said.

He said the average time between injection and symptoms appearin g in patients in Tennessee has been 16 days.

"It would not be unreasonable to consider that we may be discovering newly identified as late as the end of this month and into November," he said.

Dr. David Reagan, chief medical officer with the Tennessee health department, said most people who were exposed to the possibly contaminated injections will not develop fungal meningitis.