“A vaccine to prevent cervical cancer, triggered by the human papillomavirus (HPV), has helped reduce the number of teenage girls developing abnormalities in their cervix by as much as 50 percent in a study in Australia,” according to a report published Friday in the Lancet, Reuters reports. 

Australia implemented a national, publicly funded HPV vaccination program for all women ages 12 to 26 between 2007 and 2009. Researchers analyzed data from a regional cervical cancer registry, comparing pap smear test results prior to the immunization program and following its introduction (Lyn, 6/16). The proportion of women younger than 18 showing high-grade abnormalities (HGA) dropped from 0.80 percent to 0.42 percent, but there was no drop in the percentage of women 18 and older showing HGA, according to the Guardian.  

Writing in a Lancet commentary, Mona Saraiya and Susan Hariri of the CDC “said they wanted to know more about the vaccine status of the individuals (each woman is supposed to have three shots) and wanted more work to establish whether the reductions in potential cancers were really a result of vaccination or some other cause,” the Guardian writes (Boseley, 6/17).