The main culprit in the meningitis outbreak

Kathie Hodge is an associate professor of mycology, the study of fungi, at Cornell University. She teaches medical and veterinary mycology, and is an expert on the biodiversity of fungi. Hodge comments on the fungus Exserohilum, the main culprit in the ongoing meningitis outbreak linked to contaminated steroid medication that has claimed 42 lives and sickened almost 250 people in the United States.

Hodge says:

"The Centers for Disease Control have identified the culprits from a handful of fungal meningitis cases, and most often they've found a fungus called Exserohilum. This is a genus of molds. Its 19 species usually cause leaf diseases of grasses, including crops like corn and millet, and are not a danger to people or animals. But a few Exserohilum species can also infect us, though they do so very rarely.

"The human body is usually good at defeating fungi. Most fungi, even when we are exposed to them in high concentrations, aren't able to grow in our bodies. But, very tragically, some vials of the recalled steroid medications appear to have been infested with a fungus that can do so. Fungal meningitis is a rare disease that usually arises only when other conditions impair immunity. This outbreak affects otherwise healthy people who received apparently contaminated injections in the spinal column or joints.

"This is a terrible, terrible situation."