Observation on the remarkable stability of transmissible mink encephalopathy virus

Area of Science:

• Veterinary Pathology
• Prion Disease Research
• Infectious Disease Surveillance

Background:

• Transmissible mink encephalopathy (TME) is a fatal prion disease affecting mink.
• Understanding the stability of the TME agent is crucial for disease control and laboratory safety.
• Prion diseases are known for their resistance to conventional inactivation methods.

Purpose of the Study:

• To determine the long-term biological activity of the Transmissible mink encephalopathy (TME) virus.
• To assess the viability of TME virus stored in common laboratory preservation methods.
• To provide guidance on handling potentially contaminated TME tissues.

Main Methods:

• Storage of TME-infected tissues in formalin for approximately 3.5 years.
• Storage of TME-infected tissues in paraffin blocks for approximately 6.5 years.
• Biological assays to confirm the infectivity of the stored TME virus (details not provided in abstract).

Main Results:

• The TME virus retained biological activity after prolonged storage in formalin.
• The TME virus remained infectious even after extended storage in paraffin-embedded tissue blocks.
• These findings indicate significant stability of the TME agent under these conditions.

Conclusions:

• TME virus can remain infectious for extended periods in formalin and paraffin-embedded tissues.
• Formalin-fixed and paraffin-embedded TME tissues must be treated as potentially infectious.
• Strict handling protocols are necessary for TME-contaminated materials to prevent laboratory-acquired infections and environmental contamination.