Pertussis in an infant.

This paper reports a one-month-old female with a one-week history of low grade fever and rhinorrhea, and one day of intermittent cough and cyanosis. The signs and symptoms are typical for pertussis in an infant less than six months old. The incidence of pertussis in the neonate and infant appears to be increasing. The disease still carries significant morbidity and mortality, especially in this age group. Pertussis should be included in the differential diagnosis of protracted cough with cyanosis or vomiting, persistent rhinorrhea, and marked lymphocytosis in children under six months of age.