Old enemies, still with us after all these years

Area of Science:

• Laboratory animal science
• Infectious disease in research animals
• Rodent health management

Background:

• Certain infectious agents remain prevalent in laboratory rodents despite advances in animal care.
• Common persistent infections include rodent parvoviruses, mouse rotavirus, Theilers murine encephalomyelitis virus (TMEV), mouse hepatitis virus (MHV), and pinworms.

Purpose of the Study:

• To identify persistent infectious agents in laboratory rodents.
• To understand the reasons for the continued prevalence of these agents.
• To propose strategies for the elimination of these infections.

Main Methods:

• Review of existing literature and surveillance data on common rodent pathogens.
• Analysis of agent-specific characteristics contributing to persistence (e.g., resistance, shedding, detection difficulty).
• Consideration of factors exacerbating disease spread (e.g., shipping, immunodeficient models, wild rodent incursions).

Main Results:

• Parvoviruses, rotavirus, TMEV, MHV, and pinworms remain significant challenges in research facilities.
• Persistence is attributed to factors like environmental resistance, prolonged shedding, and diagnostic limitations.
• Increased interinstitutional shipping and use of immunocompromised rodents may facilitate spread.

Conclusions:

• Eliminating persistent rodent infections necessitates enhanced detection methods.
• Strict adherence to biosecurity protocols is crucial for preventing pathogen spread.
• Comprehensive eradication programs are required to maintain pathogen-free research animal populations.