02/09/2012 08:52 pm ET Updated Feb 10, 2012

Marin Mad Cow-Related Illnesses: Two Reported Cases, One Fatal, Rattle Bay Area County (Video)

Two residents of bucolic Marin County, just across the Golden Gate Bridge from San Francisco, have been diagnosed with Creutzfeldt-Jakob disease, a rare brain disease often associated with mad cow disease.

Aline Shaw, one of the two Marin residents who contracted the disease, has since died.

Two cases of the same extremely rare and incredibly dangerous disease in a short amount of time has led some to worry about a mass contamination of meat in the area.

However, local health officials have urged caution. "There is no information suggesting a causal link between the two cases," Marin interim public health officer Dr. Craig Lindquist told the Marin Independent Journal, "nor is there any information that suggests a risk to the public."

Creutzfeldt-Jakob disease afflicts one out every million people around the world each year and can come from one of two sources. The vast majority of those stricken with the disease either have it spring up for an unknown reason or inherit the trait from a parent. A small fraction of all cases, about one percent, stem from people eating contaminated beef--which is called variant Creutzfeldt-Jakob.

Both forms of Creutzfeldt-Jakob disease result in rapid onset dementia and ultimately death.

After running a number of tests, one of the two cases has been determined to be the non-beef-related form of Creutzfeldt-Jakob; the source of the other has yet to be determined.

If the second case is determined to have come from eating contaminated beef, it would be the first ever reported case of someone in the United States contracting the the disease from eating American beef.

ABC-7 notes that Shaw lived in England in the 1990s during an outbreak of the variant form of the disease there. Creutzfeldt-Jakob can lie dormant for years after ingestion before manifesting symptoms.

Check out this video on the risks associated with Creutzfeldt-Jakob disease: