Pertussis, also known as whooping cough, is a respiratory infectious disease primarily caused by the Bordetella pertussis or Corynebacterium diphtheriae bacteria. It is contagious and has a prolonged course, often leading to paroxysmal spasmodic coughing. It is commonly seen in infants and spreads through airborne droplets and close contact. The disease is generally prevented through vaccination. It has been included in the national free vaccination program, with babies receiving injections at three, four, and five months of age as part of their basic immunization, followed by a booster shot after the age of two. Once antibodies are produced, they can effectively prevent the disease.