(CNN) -- Thirteen patients who underwent surgery this summer may have been exposed to a fatal brain disease after their surgeries were performed using the same potentially contaminated medical equipment, according to health officials in two states.
The specialized equipment was originally used to operate on a patient now suspected of having Creutzfeldt-Jakob disease, the New Hampshire Department of Health and Human Services announced Wednesday. The now-deceased patient had neurosurgery at Catholic Medical Center in Manchester, New Hampshire. The only way to confirm the illness is with an autopsy.
The New Hampshire Department of Health and Human Services announced Wednesday that it is monitoring eight patients who were operated on with the same equipment for signs of the fatal brain disease.
On Thursday, the Massachusetts Department of Public Health followed with its own statement, saying five additional patients who underwent surgery at a Cape Cod Hospital may also have been exposed.
The surgical equipment used at both hospitals was from Medtronic Inc. according to the Massachusetts Department of Public Health.
Normal sterilization procedures don't get rid of Creutzfeldt-Jakob disease proteins, known as prions, according to the Department of Health and Human Services. Most medical devices are sterilized by heat, but the World Health Organization recommends the use of a caustic chemical like sodium hydroxide to disinfect equipment that may have come in contact with tissues that could cause Creutzfeldt-Jakob disease.
It's common for hospitals to share this kind of specialized medical equipment, said Dr. Donald Guadagnoli, chief medical officer for Cape Cod Healthcare.
"People apparently are unaware, at least in some specialties, that it is regularly common for instruments to be moved around, to be rented and loaned," he said. "We are comfortable with our sterilization process."
The five patients in Massachusetts each had spinal cord surgery at Cape Cod Hospital between July and August, and all the potentially affected patients have been notified of the risk, the Massachusetts Department of Public Health said.
The department added that the risk to the potentially affected patients is very low because they underwent spinal cord surgery instead of brain surgery. There is no danger to hospital staff or members of the public, according to the statement.
"Our concern is with the health and well-being of the eight patients who may have been exposed to CJD," Dr. Joseph Pepe, Catholic Medical Center's CEO, said in a statement Wednesday. "We will work closely with these families to help them in any way possible, even though the risk of infection is extremely low."
An autopsy of the original patient to confirm the illness -- which differs from a variant of Creutzfeldt-Jakob disease commonly known as "mad cow disease" -- is being conducted at the National Prion Disease Pathology Surveillance Center, Catholic Medical Center said Wednesday (PDF).
The Centers for Disease Control and Prevention says that no cases of the disease have been linked to the use of contaminated medical equipment since 1976.
Creutzfeldt-Jakob disease strikes fewer than 400 people a year in the United States, according to the CDC. Victims show signs of memory loss and cognitive difficulty early on; the ailment is "rapidly progressive and always fatal," the CDC says.
CNN's Jacque Wilson, Matt Smith, Miriam Falco and Jennifer Bixler contributed to this report.