Whooping cough, also called pertussis, is a highly contagious respiratory tract infection. Whooping cough primarily affects young children who have not completed the full course of vaccinations. Symptoms appear mild at first including runny nose, sneezing, mild fever, and dry cough. After one to two weeks, the symptoms worsen. More severe symptoms include prolonged coughing attacks that provoke vomitting, result in red or blue face, and cause extreme fatigue. During coughing attacks the coughs may end with a high-pitched "whoop" sound during an inhale.