Children are supposed to receive their first of 5 vaccinations against the disease at 2 months of age, and they also need a booster shot by age 11.  Whooping cough is highly contagious and usually is spread by coughing or sneezing while in close contact with others.  While it's life-threatening in newborns and infants who are too young to be fully vaccinated, it can be serious at any age.