Feb. 27, 2007 -- Human papillomavirus is common among U.S. women, especially those in their early 20s, says the CDC.
Human papillomavirus (HPV) is America's most common sexually transmitted infection. HPV infection typically clears within two years, and most infected people don't realize they have the virus.
However, some strains of HPV can cause cervical, anal, and other genital cancers, note the CDC's Eileen Dunne, MD, MPH, and colleagues.
Dunne's team calculated the total number of U.S. women aged 14-59 with HPV infection from 2003 to 2004.
More than one in four U.S. women in that age range -- nearly 27% -- had HPV infection.
That equals nearly 25 million U.S. women, according to the CDC.
About 3 million had any of the four HPV strains targeted by Gardasil, a vaccine designed to prevent cervical cancer and genital warts, the CDC estimates.
HPV Infection in Young Women
HPV infection was most common among women aged 20-24. Nearly half of the women in that age group (49%) had HPV infection.
A third of women aged 14-24 had HPV infection. That's nearly 7.5 million -- far more than previous estimates that 4.6 million women in that age range had HPV.
Older women were less likely to have HPV infection, the study shows.
Data came from 1,921 women who submitted self-collected vaginal swabs for a national health study conducted from 2003 to 2004.
The findings appear in The Journal of the American Medical Association.
The data was gathered before Gardasil became available.
Gardasil's debut may change HPV prevalence, note journal editorialists Susan Weller, PhD, and Lawrence Stanberry, MD, PhD, of the University of Texas Medical Branch at Galveston.
They recommend tracking HPV prevalence over time, in part, to see how Gardasil affects the number of women with HPV strains targeted by the vaccine.