What condition is primarily caused by Bordetella pertussis?

Bordetella pertussis is the causative agent of whooping cough, also known as pertussis. This highly contagious respiratory disease is characterized by severe coughing fits that can result in a distinctive "whooping" sound when the person breathes in after a coughing fit. The bacterium adheres to the ciliated cells of the respiratory epithelium, leading to inflammation and increased mucus production, which disrupts the normal respiratory function and contributes to the unique cough reflex associated with the disease.

While pneumonia, lung cancer, and bronchitis are respiratory conditions, they are not directly caused by Bordetella pertussis. Pneumonia can be caused by various pathogens, including bacteria and viruses, whereas bronchitis generally refers to the inflammation of the bronchi, often as a result of viral infections or irritants. Lung cancer is a neoplastic condition primarily associated with long-term risk factors such as smoking and does not have a direct link to infections caused by Bordetella pertussis. Thus, whooping cough is specifically associated with this pathogen and stands out as the primary condition it causes.