Primary pneumonic plague in the African Green monkey as a model for treatment efficacy evaluation

R Colby Layton1, Trevor Brasel, Andrew Gigliotti

  • 1Lovelace Respiratory Research Institute, Albuquerque, NM, USA.

Abstract

Insights

African Green monkeys exposed to aerosolized Yersinia pestis developed rapidly fatal pneumonic plague. Fever onset reliably signals disease progression, establishing this model for testing antibiotic treatments.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Veterinary Medicine

Background:

  • Primary pneumonic plague is a rare but severe human disease.
  • The FDA 'Animal Rule' permits testing treatment efficacy in animal models.
  • Developing a suitable animal model is crucial for plague research.

Purpose of the Study:

  • To establish and validate a Yersinia pestis-induced pneumonic plague model in African Green monkeys (AGMs).
  • To identify reliable indicators of disease onset and progression for treatment efficacy studies.

Main Methods:

  • Ten AGMs inhaled aerosolized Yersinia pestis strain CO92 at doses of 44-255 LD(50).
  • Disease progression was monitored using continuous telemetry, arterial blood gases, chest radiography, blood cultures, and clinical pathology.

Main Results:

  • Fever onset (>39°C), detected by telemetry 52-80 hours post-exposure, was the earliest sign of systemic disease.
  • Secondary indicators of severity included tachypnea, bacteremia, pneumonia extent on radiography, and elevated lactate dehydrogenase.

Conclusions:

  • Inhaled Yersinia pestis infection in AGMs causes rapidly progressive, uniformly fatal pneumonic plague.
  • This model, characterized by fever and multifocal pneumonia, is suitable for rigorous antibiotic efficacy testing.