Scientific Publications by FDA Staff

Infect Immun 2018 Oct 25;86(11):e00511-18

Histopathology of Bordetella pertussis in the baboon model.

Zimmerman LI, Papin JF, Warfel J, Wolf RF, Kosanke SD, Merkel TJ

Pertussis is a severe respiratory disease caused by Bordetella pertussis The classic symptoms of pertussis include paroxysmal coughing with an inspiratory whoop, post-tussive vomiting, cyanosis, and persistent coryzal symptoms. Infants under two months of age experience more severe disease with most deaths occurring in this age group. Most of what is known about the pathology of pertussis in humans is from the evaluation of fatal human infant cases. The baboon model of pertussis provides the opportunity to evaluate the histopathology of severe, but non-fatal pertussis. The baboon model recapitulates the characteristic clinical signs of pertussis observed in humans including leukocytosis, paroxysmal coughing, mucus production, heavy colonization of the airway, and transmission of the bacteria between hosts. As in humans, the baboons demonstrate age-related differences in clinical presentation with younger animals experiencing more severe disease. We examined the histopathology of five to six-week old baboons with findings similar to those reported for fatal human infant cases. In juvenile baboons, we found that the disease is highly inflammatory and concentrated to the lungs with signs of disease that would typically be diagnosed as acute respiratory distress syndrome (ARDS) and bronchopneumonia. In contrast, no significant pathology was observed in the trachea. Histopathological changes in the trachea were limited to cellular infiltrates and mucus production. Immuno-histostaining revealed the bacteria localized to the surface of the ciliated epithelium in the conducting airways. Our observations provide important insights into the pathology of pertussis in typical, severe, but non-fatal pertussis cases in a very relevant animal model.