ST. PAUL, Minn. (AP) — About 25 people in Minnesota who were injected with a steroid from a Massachusetts specialty pharmacy are being evaluated for fungal meningitis in a widening national outbreak, Minnesota’s top disease investigator said Friday.

State epidemiologist Ruth Lynfield said the number of those being evaluated is likely to fluctuate as health officials and a group of Minnesota pain clinics track down about 700 patients who received spinal injections of the steroid linked to the outbreak.

Lynfield said it’s difficult to know how many could be affected because the form of meningitis is rare and the outbreak is still developing.

“We’re having a very low threshold to have people evaluated,” Lynfield said.

Two Minnesota clinic chains used the now-recalled product. They are Medical Advanced Pain Specialists, or MAPS, in Edina, Fridley, Shakopee and Maple Grove; and the Minnesota Surgery Center in Edina and Maple Grove. MAPS owns the Minnesota Surgery Center clinics.

“There’s a massive effort to contact all the patients,” said Marsha Thiel, MAPS’ chief executive officer. “If there’s any question at all, they’re being directed to go to their physician.”

Thiel said the Minnesota clinics received the steroid from the New England Compounding Center on July 3, and stopped using it Sept. 26. She said the clinics got two batches of the product, and used the first on 100 patients and the second on approximately 600.

“This just happened to be our supplier and we happened to get the lots that are in question,” Thiel said.

The meningitis in question cannot be spread from person to person. The Minnesota Health Department said symptoms of infection typically show up within one to four weeks of an injection, but could start sooner or develop later.

Lynfield said symptoms can include a worsening headache, stiff neck, fever, numbness or difficulty speaking. She said the patients who received the steroid already have chronic pain that can include headaches, which makes it more difficult to identify meningitis symptoms.

A spinal tap is needed to test for this kind of meningitis, and the treatment is antifungal medicine that typically would be given in a hospital.

“There’s a lot about this we don’t know, but what seems to be happening in the cases we have information on is that sometimes they can have mild symptoms for a period of time and then they get sicker,” Lynfield said.

State health officials are also contacting patients who got the steroid injected into joints or other body parts instead of their spines.

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