An outbreak of rare fungal meningitis in the US has now affected 47 people in seven states, Center for Disease Control (DCD) officials say.
Doctors at about 75 medical clinics are being warned to alert patients who received suspect steroid injections.
Five people have died from the illness, which the CDC has linked to products from a Massachusetts-based pharmacy firm.
Officials say they found contamination in a sealed steroid vial at the New England Compounding Center.
The firm recalled the steroid doses and has since shut down operations, but the vials have already been shipped to 23 states.
Meningitis is an inflammation of the lining of the brain and spinal cord. Symptoms include severe headache, nausea, and fever as well as slurred speech and difficulty walking.
The fungal meningitis causing concern in the US is not infectious, the CDC says.
Confirming that 47 people were now affected – an increase of 12 in the space of 24 hours, the CDC said new cases were reported for the first time in Michigan.
In Tennessee, which has the majority of the cases, a total of 29 people have now fallen ill. There were six cases in Virginia, three in Indiana Indiana, two each in Maryland and Florida and one in North Carolina, the CDC said.
It is not yet clear how many patients may have been exposed to any contamination, and fungal meningitis can have a lengthy incubation period.
A briefing by the CDC and the Food and Drug Administration (FDA) on Thursday said a fungus linked to the steroid medication had been identified in tests of five patients.
“Out of an abundance of caution, we advise all health care practitioners not to use any product” from the company, said Ilisa Bernstein, director of compliance for the FDA’s Center for Drug Evaluation and Research.
New England Compounding Center is a type of pharmacy that mixes ingredients for customized medicines. The steroid in question was three lots of methylprednisolone acetate from the firm.
On Friday, the CDC listed about 75 clinics and medical centres that received the suspected lots, and told doctors to immediately contact patients who have had an injection.
Tests are under way to confirm if the contamination is the same fungus blamed in the outbreak. The disease cannot be passed from person to person.
Three people have died in Tennessee, with one death in Virginia and one in Maryland, reports say.