On Monday, federal researchers revealed that a vaccine introduced ten years back to fight the sexually transmitted virus that leads to cervical cancer has already decreased the virus’ prevalence in teenage girls by nearly two-thirds.

In fact for women in their early 20s, a group with lower vaccination rates, the most unsafe strains of human papillomavirus, or HPV has still got decreased by over a third.

Dr. Amy B. Middleman, the chief of adolescent medicine at the University of Oklahoma Health Sciences Center, said, “We’re seeing the impact of the vaccine as it marches down the line for age groups, and that’s incredibly exciting. A minority of females in this country has been immunized, but we’re seeing a public health impact that is quite expansive”. Dr. Amy wasn’t involved in the study.

The news could serve as a welcome boost in the tumultuous effort of encouraging HPV vaccination in the United States. In spite of the proven effectiveness of the vaccine, immunization rates are low in nearly 40% of girls and 20% of boys of the age group 13 to 17 years.

It is partially due to the vaccine’s implicit link with adolescent sexual activity, rather than with its clear intention: cancer prevention. The HPV vaccine is required just in Virginia, Rhode Island and the District of Columbia.

The focus of the recent efforts has been on recommending the vaccine for children of ages 11 and 12 years, when their immune response is healthier in comparison to that of teenagers and when most of states need two other vaccines, including tetanus, diphtheria and pertussis, vaccine and other one for meningococcal disease. These vaccines’ immunization rates are 80% and higher.