(ATLANTA) -- Health officials estimate that 13,000 people may have been exposed to contaminated lots of an epidural steroid that has been linked to a rare fungal meningitis that has infected 105 people across nine states, killing eight of them. Fourteen new cases and one new death have been reported since Sunday.
Although the number of cases has increased, the outbreak does not include any new states. The number of people with fungal meningitis, which is not spread person-to-person, has grown by 64 percent since Friday.
The outbreak of aspergillus meningitis has been linked to spinal steroid injections, a common treatment for back pain. A sealed vial of the steroid, called methylprednisolone acetate, was found to contain fungus, according to the U.S. Food and Drug Administration.
The states with reported cases include Florida, Indiana, Maryland, Michigan, Minnesota, North Carolina, Ohio, Tennessee and Virginia. Tennessee has the most cases, with 35, including four deaths.
"FDA is in the process of further identifying the fungal contaminate," said Dr. Ilisa Bernstein, acting director of the FDA's Center for Drug Evaluation and Research Office of Compliance. "Our investigation into the source of this outbreak is still ongoing."
The steroid came from the New England Compounding Center in Framingham, Mass., a specialty pharmacy that has recalled three lots of the drug and shut down operations. Calls to the pharmacy were not immediately returned and its website is down.
Roughly 75 clinics in 23 states that received the recalled lots have been instructed to notify all affected patients.
"If patients are concerned, they should contact their physician to find out if they received a medicine from one of these lots," said Dr. Benjamin Park of the U.S. Centers for Disease Control and Prevention, adding that most of the cases occurred in older adults who were healthy aside from back pain.
Meningitis affects the membranous lining of the brain and spinal cord. Early symptoms of fungal meningitis, such as headache, fever, dizziness, nausea and slurred speech, are subtler than those of bacterial meningitis and can take nearly a month to appear. Left untreated, the inflammatory disease can cause permanent neurological damage and death.
"Fungal meningitis in general is rare. But aspergillus meningitis -- the kind we're talking about here -- is super rare and very serious," said Dr. William Schaffner, president of the National Foundation for Infectious Diseases and chairman of preventive medicine at Vanderbilt University Medical Center in Nashville. "There's no such thing as mild aspergillus meningitis."
The disease is diagnosed with a lumbar puncture, which draws cerebrospinal fluid from the spine that can be inspected for signs of the disease. Once detected, it can be treated with high doses of intravenous antifungal medications.
"Treatment could be prolonged, possibly on the order of months," said Park, adding that the IV treatment would require a hospital stay.
Unlike bacterial and viral meningitis, fungal meningitis is not transmitted from person to person and only people who received the steroid injections are thought to be at risk.
The FDA has, however, advised health providers to stop using any product made by the New England Compounding Center during the investigation.
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