The Indiana Youth Institute's annual Kids Count Data Book takes a look at a number of health issues facing Hoosier kids.

An outspoken critic of the state's vaccination reminder letter seems to have sparked several changes in the language of those letters, and health experts worry fewer parents will now vaccinate their children against human papillomavirus (HPV).

Flu season occurs annually, typically starting around October and continuing through May. The health department says seasonal flu viruses can vary from year to year, so it is important to get a flu vaccine every year.

The state's Children and Hoosier Immunization Registry Program has been used in the past by state and county health departments. But its effectiveness was limited because only a handful of health care providers used the database.