noun, Psychology. 1. Also called operant conditioning, instrumental conditioning. a process of changing behavior by rewarding or punishing a subject each time an action is performed until the subject associates the action with pleasure or distress.
Pertussis is caused by the bacterium Bordetella pertussis. It is an airborne disease which spreads easily through the coughs and sneezes of an infected person. People are infectious to others from the start of symptoms until about three weeks into the coughing fits.
Pertussis (Whooping Cough). Pertussis, also known as whooping cough, is a toxin-mediated disease caused by the bacteria Bordetella pertussis.ertussis vaccination reduces the frequency and severity of disease. However, the protective effects of natural pertussis infection and pertussis vaccine wane with time. Unrecognized infections in older children and adults are the most common source of pertussis transmission to infants in the community.