A health worker has lifted the lid after a mysterious brain illness began striking down young people in the Canadian province of New Brunswick. 

According to The Guardian, a cluster has emerged in the region over the past two years, with victims experiencing a range of disturbing symptoms such as swift and significant weight loss, insomnia, hallucinations, problems thinking clearly and reduced mobility. 

Doctors remain stumped, with the illness seemingly affecting previously healthy young people, including those aged in their 20s and 30s. 

According to the New Brunswick Office of the chief medical officer of health, 48 cases are being investigated, but insiders claim that number could be as high as 150. 

Of those 48 official cases, 46 were reported by a single neurologist, while the two other cases were referred by two separate neurologists. 

The illness was originally thought to be a human prion disease, which occurs when proteins, known as prions, caused regular proteins to fold abnormally. However, tests have since ruled out that theory. 

Speaking to The Guardian, a whistle-blower from health authority Vitalité Health Network said they did not believe the illness was affecting New Brunswick alone. 

"We're probably the area that is raising the flag because we're mostly rural and, in an area, where people might have more exposure to environmental factors," the source said. 

"I'm truly concerned about these cases because they seem to evolve so fast. 

"I'm worried for them and we owe them some kind of explanation." 

The publication reports that at least nine cases involve people in close contact with a confirmed case, and that those cases were not genetically linked, indicating it could potentially be spreading from person to person. 

Alarm bells were first raised last March, after a leaked government memo urged doctors to be on alert for symptoms which resembled the rare, fatal Creutzfeldt-Jakob brain disease. 

The New Brunswick Office of the Chief Medical Officer of Health reports that "between early 2020 and the end of May, 2021, there were a total 48 individuals who were identified as having some clinical signs and symptoms that were similar to those associated with Creutzfeldt-Jakob disease (CJD) yet presented with atypical characteristics". 

"At the time of referral by their healthcare provider, most of the individuals under investigation were living in the southeastern and northeastern regions of New Brunswick, around the Acadian Peninsula and Moncton areas," the website states. 

"However, the investigation has not found any evidence suggesting that the residents of these regions are more at risk than those living elsewhere in the province. 

"It is also noted that locations could be a reflection of the catchment area of the referring physicians. No other cases have been identified in other provinces and territories." 

The organisation noted that while all test results have been negative for known forms of human prion disease, "due to some noted commonalities in signs and symptoms and the lack of a confirmed diagnosis among cases, the individuals were categorised as being part of a cluster of a potential neurological syndrome of unknown cause". 

A report is expected to be released this month which could reveal whether the 48 cases were genuine, or the result of misdiagnoses. 

- by Alexis Carey, news.com.au