Pertussis

(per-tus'-is). Whooping-cough, a contagious disease, confined usually to childhood and youth, and marked by spasmodic coughing ended by a " whoop, " and sometimes by vomiting. Its course lasts usually for a period of six or seven weeks. It is rarely fatal. It is divided into a catarrhal or prodromal stage, and a paroxysmal stage. The period of incubation is about two weeks. During the height of the disease, hemorrhages may occur from the nose, mouth, or ears, or into the sub conjunctival ti ues, even into the brain or its meninges. Bronchopneumonia isa frequent complication. Affanasiew has found a small bacillus in the expectoration, which he considers the etiologic factor. The presence of this bacillus has been confirmed by others. See Bacillus tu is convulsive? under Bacteria, Synonymatic Table of.