The vaccinations also help the community around her. The teen won't come down with a life-threatening disease and the whole community is protected from outbreaks -- if enough people are vaccinated.

The Mecklenburg County department, with "Protecting and Promoting the Public's Health" emblazoned on its van, is similar to other U.S. health departments. They run programs to reduce suicides and drug overdoses, improve prenatal health and help people stop smoking. They educate people about health and test for and treat diseases such as HIV and tuberculosis. Some, including Mecklenburg, operate medical and dental clinics too.