diseases. so just what is a vaccine? in a weakened form that doesn t make you sick. into producing antibodies to give you immunity to a disease without ever having it in the first place. preventing disease before it occurs as showing it in the fight against polio. vaccines are effective, safe and incredibly important. and a list of vaccine preventable diseases is long. hepatitis b, measles, mumps, pneumonia, polio, rue bell la, tetanus and more. vaccines that have prevented deaths worldwide. this is house to house, polio campaign. but science often loses the argument to ideology. and that was the case in nigeria.