For many years now, we have been fortunate to live in an environment where vaccine-preventable diseases are mostly a thing of the past. So why are vaccines still important? Marion patiently explained each disease contained in the vaccines. I now have a better understanding of what diphtheria, tetanus, rotavirus and poliomyelitis are and I learned more about whooping cough, haemophilus influenzae type B and pneumococcus, which can cause severe illness in infants and children. Vaccines protecting against meningitis, measles, mumps and rubella are also a part of the schedule because these viruses can cause serious brain damage and developmental issues. Marion added that measles epidemics are starting to appear all over the world and, because of the virus’s highly contagious nature, 95 percent of the population needs to be immunized to achieve herd immunity, which is far from the percentage currently vaccinated, even in Canada.