Pertussis is a contagious, bacterial respiratory disease.
Although pertussis may be a mild disease in older children and adults, in younger children this disease can be complicated by pneumonia and occasionally inflammation of the brain. The symptoms of pertussis usually occur in stages. The first stage usually begins like a cold, with a runny nose, sneezing, low-grade fever and cough. The cough lasts one to two weeks and then becomes worse. The second stage of pertussis includes uncontrolled coughing spells followed by a whooping noise when a person breathes in.