The Exserohilum fungus is the source of the current fungal meningitis outbreak in the U.S. The common mold is found in soil and on plants. (CDC/Associated Press)

U.S. health officials have raised the death toll from a fungal meningitis outbreak to 15 with almost 200 people infected.

A second person has died in Indiana after receiving a tainted steroid injection for back pain, state and federal health officials said Saturday.

The Centers for Disease Control and Prevention (CDC) reported the second death on its website and said three additional cases of the rare disease had been reported in Indiana, raising the state's total to 27. The outbreak has affected 13 states.

Indiana's cases involve patients at six health facilities that received a steroid recalled by a Massachusetts specialty pharmacy. Those clinics are in Elkhart, Evansville, Fort Wayne, South Bend, Terre Haute and Columbus.

Officials at the clinics in Elkhart and Terre Haute told The Associated Press that the second death was not linked to their facilities.

A spokeswoman for the clinic in Fort Wayne said earlier this week she did not believe any of the reported meningitis cases were contracted at her clinic because the current outbreak was spread through spinal injections, which her facility does not administer.

A spokeswoman at the Evansville clinic said she didn't know if the new death was one of its patients, and the clinics in South Bend and Columbus did not respond to phone calls Saturday.

Lisa Ann Durbin of Decatur, Mich., said Saturday her family was still awaiting results from her grandmother's autopsy. Pauline Burema, 89, of Cassopolis, Mich., died Wednesday at a daughter's home in Bristol, Ind.

Doctors told the family they think Burema contracted fungal meningitis from shots she received Aug. 22 and Sept. 8 at OSMC Outpatient Surgery Center in Elkhart.

As of mid-week, health authorities said they had tracked down 12,000 of the roughly 14,000 people who may have received contaminated steroid shots in a growing meningitis outbreak.

They warned that patients will need to keep watch for symptoms of the deadly infection for months.

Meningitis is an inflammation of the lining of the brain and spinal cord. Symptoms include severe headache, nausea, dizziness and fever. Fungal meningitis is not contagious like the more common forms.

Fungus has been found in at least 50 vials of an injectable steroid medication made at a specialty compounding pharmacy in Massachusetts, investigators said. Health authorities haven't yet said how they think the medication was contaminated, but they have ruled out other suspects — other products used in administering the shots — and the focus continues to be on that pharmacy, the New England Compounding Center.

Last month, after illnesses began coming to light, the company recalled three lots of the steroid medicine — known as preservative-free methylprednisolone acetate— that were made in May, June and August. The recall involved about 17,700 single-dose vials of the steroid sent to clinics in 23 states.