A 3-month-old infant is brought to the emergency department…

A 3-month-old infant is brought to the emergency department by the parents who report episodes of prolonged, uncontrollable coughing episodes that include brief periods of apnea. The infant appears exhausted following the coughing episodes. On assessment, the nurse notes nasal congestion, mild cyanosis during coughing, and a low-grade temperature. What respiratory illness is the infant most likely experiencing?