A boy with pertussis The classic symptoms of pertussis are a paroxysmal cough, inspiratory whoop, and fainting, or vomiting after coughing. The cough from pertussis has been documented to cause subconjunctival hemorrhages, rib fractures, urinary incontinence, hernias, and vertebral artery dissection. Violent coughing can cause the pleura to rupture, leading to a pneumothorax. Vomiting after a coughing spell or an inspiratory<unk>  sound on coughing, almost doubles the likelihood that the illness is pertussis. The absence of a paroxysmal cough or posttussive emesis, though, makes it almost half as likely. The illness usually starts with mild respiratory symptoms include mild coughing, sneezing, or a runny nose (known as the catarrhal stage). After one or two weeks, the coughing classically develops into uncontrollable fits, sometimes followed by a high-pitched "whoop" sound, as the person tries to inhale. About 50% of children and adults "whoop" at some point in diagnosed pertussis cases during the paroxysmal stage. This stage usually lasts two to eight weeks, or sometimes longer. A gradual transition then occurs to the convalescent stage, which usually lasts one to four weeks. This stage is marked by a decrease in paroxysms of coughing, although paroxysms may occur with subsequent respiratory infection for many months after the onset of pertussis. Symptoms of pertussis can be variable, especially between immunized and non-immunized people. Those that are immunized can present with a more mild infection; they may only have the paroxysmal cough for a couple of weeks, and it may lack the<unk> " characteristic. Although immunized people have a milder form of the infection, they can spread the disease to others who are not immune. Incubation period The time between exposure and the development of symptoms is on average 7–14 days (range 6–20 days), rarely as long as 42 days.
Whooping cough
Common cold
Croup
Post-viral cough
Bronchorrhea
Katrina cough
Dust pneumonia
Allergic rhinitis