Girls and boys nationwide have a new vaccination schedule to follow.
The American Academy of Pediatrics and the Centers for Disease Control are recommending vaccine changes, starting with a meningitis booster shot for 16 year olds.
Meningitis is a potentially deadly bacterial infection.
Doctors say children should get vaccinated at age 11.
The vaccine weakens over time, leaving as many as half of those kids by age 16.
Texas has already made the shot mandatory to attend college.
Another change: Doctors now say boys as well as girls can get the HPV shot as early as age 9.
Human Papilloma Virus is transmitted sexually and linked to cervical cancer in women, but certain HPV strains are also the cause of many head and neck cancers, particularly in men.
Doctors say the vaccine is most effective at creating HPV antibodies when kids reach age 11 or 12, often before they reach sexual maturity.
"If you wait until you think you they're sexually active, you may miss the opportunity to protect them," warns Dr. Michael Brady of Nationwide Children's Hospital.
Protecting them now gives them the best shot possible at a healthier life.
Kids aren't the only targets for the new vaccine schedule.
Babies too young for a flu shot and the Whooping Cough vaccine can be born with antibodies to both illnesses if their mothers had the shots while pregnant.