Four more cases of meningitis have been reported at St. Joseph Mercy Hospital in Ann Arbor.
Local 4 has learned that there are now 22 patients being treated for the disease at the hospital, up from 18 on Wednesday.
The outbreak is linked to contaminated steroid injections, and as many as 13,000 people may have received the medicine between May 21 and September 24, the CDC said.
The Centers for Disease Control and Prevention says at least 120 people nationwide have been sickened and there have been 12 fatalities.
Tennessee is the hardest-hit state, with 39 infections and six deaths, according to the CDC.
Of the remaining deaths, three occurred in Michigan and one each in Maryland and Virginia, the CDC said.
Patients contracted the deadly fungal meningitis after being injected in their spines with a preservative-free steroid called methylprednisolone acetate that was contaminated by a fungus. The steroid is used to treat pain and inflammation.
The New England Compounding Center (NECC), the Massachusetts-based pharmacy that made the contaminated injections, voluntarily recalled three lots of the injected steroid last week.
The Food and Drug Administration has already asked doctors, clinics and consumers to stop using any of the pharmacy's products. Last week, the pharmacy voluntarily surrendered its license to operate until the FDA investigation into the contamination is complete.
Health officials say 75 medical facilities in 23 states received the contaminated steroid injections from NECC.
Federal health inspectors began inspecting the NECC plant October 1. Inspectors found foreign particles in unopened vials, and after testing one of them, they determined the substance was a fungus.