HYANNIS, Mass. (WHDH) — A dangerous diagnosis is causing a lot of concern on the cape. A rare brain disease linked to a New Hampshire hospital may have spread.

The Massachusetts Department of Health announced five patients may have been exposed to Creutzfeldt-Jakob disease, a degenerative brain disease, after surgery with a potentially contaminated instrument at Cape Cod Hospital.

"We have six to seven cases of Creutzfeldt-Jakob Disease every year in Massachusetts. That’s just what the expected rate is, because this disease does occur,” Dr. Al DeMaria, state epidemiologist, said.

The fatal brain disease is rare; it affects one in a million worldwide.

It cannot be transmitted through the air or casual contact, only through contact with brain or spinal fluid.

It's also very difficult to disinfect standard cleaning doesn't work.

It is believed to have killed an elderly patient in New Hampshire. That same instrument was used on five patients in Massachusetts.

"The instruments are basically loaned to the hospital. Essentially, they're renting them for a period of time. They're at a hospital for a period of time, and then they may be rented to another hospital for a period of time,” DeMaria said. “Everything was done appropriately in terms of disinfection for routine purposes.

The disease has been described as being like a sped-up Alzheimer’s disease. Robert Blodgett, from Epsom, New Hampshire, knows that first-hand; his wife’s sister died from CJD.

"I wouldn't want anybody to go through this. She went from 120 pounds down to 60 and the heaviest part of her body was her head. It's not pretty, it's fast moving, it’s debilitating,” Blodgett said.

The chief medical officer from Cape Cod Hospital said there are risks in surgery but this disease is incredibly rare and should not be a source of worry for patients.

"The relative risk to these people is probably greater on their drive to the office than it is from this disease,” Dr. Donald Guadagnoli, Chief Medical Officer at Cape Cod Hospital, said.

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