A new study reveals that the vaccine for cervical cancer has reduced the virus's prevalence in teenage girls by almost two-thirds, New York Times reports. 

The federal researchers said that even for women in their early 20s, the most dangerous strains of human papillomavirus or HPV have been reduced by more than a third.

"We're seeing the impact of the vaccine as it marches down the line for age groups, and that's incredibly exciting," said Dr. Amy B. Middleman, the chief of adolescent medicine at the University of Oklahoma Health Sciences Center, who was not involved in the study.

"A minority of females in this country have been immunized, but we're seeing a public health impact that is quite expansive."

The latest research, published in Pediatrics examined HPV immunization and infection rates through 2012 in girls.

However, despite the effectiveness of the vaccine, only about 40 percent of girls and 20 percent of boys between the ages of 13 and 17 get immunized. This is because the vaccine is associated more with adolescent sexual activity, than with cancer prevention.   

For the study, the researchers used data from a survey by the Centers for Disease Control and Prevention. The study examined the prevalence of the virus in women and girls of different age groups during the pre-vaccine years of 2003 through 2006.

The study found that by the later years, the prevalence of the four strains of HPV covered by the vaccine had decreased by 64 percent in girls ages 14 to 19. Among women ages 20 to 24, the prevalence of those strains had declined 34 percent.

The study also found that the rates of HPV in women 25 and older had not fallen.

"The vaccine is more effective than we thought," said Debbie Saslow, a public health expert in HPV vaccination and cervical cancer at the American Cancer Society.

 Many doctors now recommend primary care providers to strongly recommend the HPV vaccine along with the other two vaccines that preteen children now typically receive.

"The infection is sexually transmitted, but that doesn't need to be part of the conversation," said Dr. Joseph A. Bocchini Jr, a pediatric infectious disease specialist at Louisiana State University in Shreveport.

"Multiple studies have shown the importance of a strong provider recommendation for increasing vaccination coverage," said Dr. Lauri E. Markowitz, a medical epidemiologist at the National Center for Immunizations and Respiratory Diseases, a division of the C.D.C., who led the research for the latest study.