Kuru with incubation periods exceeding two decades

Area of Science:

• Neurology
• Epidemiology
• Prion Diseases

Background:

• Kuru is a fatal prion disease historically prevalent in Papua New Guinea.
• Understanding kuru's clinical spectrum and transmission is crucial for public health.
• Previous studies documented kuru's neurological manifestations and association with cannibalism.

Observation:

• Fifteen kuru patients exhibited varying neurological dysfunction, from mild ataxia to severe rigidity, spasticity, and dementia.
• A consistent apprehensive facial expression was noted in all patients.
• Diminished or absent optokinetic nystagmus was observed in most patients, a novel finding in kuru.

Findings:

• The study identified prolonged incubation periods for kuru, exceeding two decades.
• Clinical features, including ataxia and dementia, remain consistent with earlier observations.
• Ritualistic cannibalism is strongly implicated as the transmission route, suggesting low-dose exposure.

Implications:

• The findings suggest that kuru can have exceptionally long incubation periods, challenging previous estimates.
• The novel clinical signs (apprehensive facies, impaired optokinetic nystagmus) may aid in earlier kuru diagnosis.
• Understanding the factors contributing to long incubation periods could inform strategies for managing other prion diseases.