Let's be clear: Vaccines work and have been proven to be safe for the vast majority of people.
Public health officials want vaccines to be mandatory because of a concept called herd immunity. Vaccines are most effective when everyone receives a vaccination. As shown by the graph below, herd immunity prevents the spread of contagions by giving the sick fewer chances to spread the disease. If enough people are immune, the disease won't affect most people. If not, it's easy to see how quickly and widely the sickness can spread.
Vaccinations should not be a matter of choice, because it is in the child's best interest—and everyone's best interest—to receive vaccinations. Without vaccinations, children can fall dangerously ill and spread diseases to others. Since vaccines have been proven to be safe and effective, and real harm can occur if an unvaccinated child causes an outbreak, medical professionals say vaccinations are actually a public health decision—not a person decision.
As a society, we have decided that parents are the best default surrogate decision-makers for their children. But we have also decided there is a limit to what parents can choose. Parents must use correct car seats and seat belts for their children; they must care for them in safe homes and provide sufficient food; they must also follow basic medical standards for their children’s health. Thus, there is ample precedent for removing the decision-making capacity from parents who are determined not to act in their child’s best interest. Take, for instance, the 2009 case of this child with leukemia who was successfully treated with chemotherapy on court order against her parents’ wishes, because they believed in “natural” treatment for cancer.
Parents who choose not to vaccinate their child say it is well within their right to decide how to raise their child. It's not the government's place to force medical treatment on anyone—especially in a non-life or death situation.
There is tremendous evidence showing vaccinations prevent childhood diseases. Should public health officials do everything they can to encourage, inform and facilitate childhood vaccinations? Yes. Do they have the right to force parents to vaccinate their children? Absolutely not.