U.S. health officials say the death toll from a multi-state fungal meningitis outbreak has risen to seven.

New data posted Saturday by the U.S. Centers for Disease Control and Prevention say the outbreak has spread to more than 60 people in nine states who have received steroid shots for back pain since July. Authorities say the rare form of meningitis, which has caused strokes in several patients, is not contagious.

Medical detectives have narrowed their search for the source of the contamination to a specialty pharmacy in Massachusetts. A fungus was found this week in at least one sealed vial of the customized steroid solution at the company's manufacturing facility.

More than 17,000 vials were immediately recalled, as investigators race to notify hundreds, if not thousands, of arthritis patients who may have received injections.

Minnesota and Ohio are the latest states to report confirmed cases linked to suspect batches of the steroid (methyl-prednisolone acetate).