A married couple presents requesting vaccination in anticipation of the birth of their first grandchild. The most important vaccine for infant contacts, given to prevent the highly contagious respiratory tract infection that produces fever, cold symptoms, and rapid coughing episodes in a child, is the ________.
1) influenza vaccine
2) pneumococcal vaccine
3) tetanus, diphtheria and acellular pertussis (Tdap) vaccine
4) H1N1 Flu vaccine