Pertussis, or whooping cough, is an upper respiratory infection caused by the Bordetella pertussis or B. parapertussis bacteria. It is a serious disease that can cause permanent disability in infants, and even death. When an infected person sneezes or coughs, tiny droplets containing the bacteria move through the air, and the disease is easily spread from person to person. Initial symptoms, similiar to the common cold, usually develop about a week after exposure to the bacteria. Severe episodes of coughing start about 10 to 12 days later. In children, the coughing often ends with a "whoop" noise. The sound is produced when the patient tries to take a breathe. The whoop is rare in patients under 6 months of age and in adults. Coughing spells may lead to vomiting. Pertussis should always be considered when vomiting occurs with coughing. In infants, choking spells are common. The infection usually lasts 6 weeks. Whooping cough can affect people of any age. Before vaccines were widely available, the disease was most common in infants and young children. Now that most children are immunized before entering school, the higher percentage of cases is seen among adolescents and adults.
| 
