1984 Tapanui & West Otago Outbreak

In 1984, an epidemic outbreak occurred in the small, rural town of Tapanui, in West Otago in New Zealand's South Island, close to the boundary with Southland region. Dr. Peter Grahame Snow was a General Practitioner in Tapanui, New Zealand when the outbreak occurred. He is considered the first doctor in New Zealand to diagnosis and treat CFS patients. His obituary states: "It was that farmer’s wisdom, that ability to see phenomena clearly, and to perceive the connections among them, that led Peter to describe an epidemic of chronic fatigue syndrome (CFS) in West Otago, a syndrome that was then recognized elsewhere in New Zealand, and that the media soon dubbed Tapanui flu."

The outbreak was characterized by flu-like malaise and prolonged unexplained fatigue. Levine, P.H., et al., stated: "This outbreak resembled other reported outbreaks of epidemic neuromyasthenia in that affected individuals presented with a spectrum of complaints ranging from transient diarrhea and upper respiratory disorders to chronic fatigue syndrome."

Two other physicians studied the illness outbreak with Dr. Snow: Dr. Marion Poore and Dr. Charlotte Paul. Together they wrote a piece in 1984 for The New Zealand Medical Journal: "An apparent epidemic of undiagnosed illness in a rural general practice was investigated. The aims were to describe the illness, the characteristics of the people affected, and to look for possible causes. The patients were questioned about their symptoms, and both patients and controls matched for age and sex, were questioned about possible aetiological factors. Twenty-eight cases were identified; all but three were less than 45 years of age; there were equal numbers of females and males. The most commonly experienced symptoms were tiredness, mood and sleep disturbances, headache, and joint or muscle pains. Results of the case-control study suggested that pollution of the water supply, zoonotic infections, contact with agricultural chemicals, and self-dosing with selenium were unlikely to be causes of this illness. An unidentified virus was regarded as the most likely cause."

A ten-year follow-up concluded that: "A return to premorbid activity was seen in most (n=16) patients, although some reported the need to modify their lifestyle to prevent relapses. A female predominance was noted in those meeting the Centers for Disease Control and Prevention (CDC) case definition for CFS, whereas males predominated in patients diagnosed as having prolonged or idiopathic fatigue." It is unknown if the difference in diagnoses between males and females was because the presentation of the disease differed in the sexes or whether physician bias lead one sex to be diagnosed differently that the other.

Eighteen years later, in 2002, Dr. Peter Snow wrote a reminiscing piece for New Zealand Family Physician journal, in which he discussed the dismissive nature in which patients of the outbreak were treated. "I can recall poems, cartoons (NZ Herald) and songs – I have got those old Tapanui flu blues... [where] the press made light, dumbing down if you wish, of the subject, which I considered an important cause of distress in our community." Later, after the medical and research fields began the view the illness seriously, the pendulum began to swing the other way. "What I find disturbing now is the exact opposite to the problem we started in 1985. Then it was getting physicians to accept that there was a chronic fatiguing condition, whereas today I fear that the diagnosis is being applied before adequate investigation has taken place often leaving the patient’s real disorder undiagnosed and untreated. Unfortunately chronic fatigue syndrome has become a convenient dumping ground for the difficult to diagnose."

To illustrate this phenomenon, Dr. Snow and Dr. Mike Holmes, of the Microbiology Department of the University of Otago, further studied the present local population with diagnoses of CFS and found that 65% were actually suffering from a bowel disorder caused by Giardia Lamblia which responded to the antibiotic, nitroimidazole. Initially left untreated, the giardia had moved into a chronic phrase, presenting as "diaorrhoea, constipation, frequent mushy bowel motions, rotten egg flatus, post prandial bloating, abdominal distention, food intolerances particularly to milk products, alcohol, fatty foods, spicy foods, along with the multiplicity of signs such as headache, lymphadenopathy and others." This symptom cluster is atypical for CFS. He cautioned other physicians that only 5% of patients with a fatiguing illness "probably is [of] the group that would fulfill the criteria of the Centre of Disease Control USA [sic] for the chronic fatigue syndrome."

Learn more

 * Medical description of Tapanui Flu
 * Dr. Peter Snow
 * "Reminiscences of the chronic fatigue syndrome" by Dr. Peter Snow
 * ANZMES - The Associated New Zealand ME Society
 * Epidemic neuromyasthenia and chronic fatigue syndrome in west Otago, New Zealand. A 10-year follow-up.