Development of an acute model of inhalational melioidosis in the common marmoset (Callithrix jacchus)

• Published in: International journal of experimental pathology Vol. 92; no. 6; pp. 428 - 435
• Main Authors: Nelson, Michelle, Dean, Rachel E., Salguero, Francisco J., Taylor, Christopher, Pearce, Peter C., Simpson, Andrew J. H., Lever, Mark S.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.12.2011
• Subjects: Acute Disease; Administration, Inhalation; animal model; Animal models; Animals; Bacteremia; Body temperature; Body Temperature - physiology; Burkholderia pseudomallei; Burkholderia pseudomallei - isolation & purification; Callithrix; Callithrix jacchus; Culling; Disease Models, Animal; Disease Progression; Female; Infection; Lethality; Liver; Liver - microbiology; Liver - pathology; Lung; Lung - microbiology; Lung - pathology; Male; marmoset; Melioidosis; Melioidosis - microbiology; Melioidosis - pathology; Melioidosis - physiopathology; non-human primate; Original; pathology; Spleen; Spleen - microbiology; Spleen - pathology; Time Factors
• DOI: 10.1111/j.1365-2613.2011.00791.x
• ISSN: 0959-9673

Summary Studies of inhalational melioidosis were undertaken in the common marmoset (Callithrix jacchus). Following exposure to an inhaled challenge with aerosolized Burkholderia pseudomallei, lethal infection was observed in marmosets challenged with doses below 10 cfu; a precise LD50 determination was not possible. The model was further characterized using a target challenge dose of approximately 102 cfu. A separate pathogenesis time‐course experiment was also conducted. All animals succumbed, between 27 and 78 h postchallenge. The challenge dose received and the time to the humane endpoint (1 °C below normal body temperature postfever) were correlated. The first indicator of disease was an increased core body temperature (Tc), at 22 h postchallenge. This coincided with bacteraemia and bacterial dissemination. Overt clinical signs were first observed 3–5 h later. A sharp decrease (typically within 3–6 h) in the Tc was observed prior to humanely culling the animals in the lethality study. Pathology was noted in the lung, liver and spleen. Disease progression in the common marmoset appears to be consistent with human infection in terms of bacterial spread, pathology and physiology. The common marmoset can therefore be considered a suitable animal model for further studies of inhalational melioidosis.