Human Papillomavirus

"High-risk HPV types are detected in 99 percent of cervical cancers, and 
worldwide approximately 70 percent of cervical cancers are due to HPV 
types 16 and 18....."

Science News

Human papillomavirus is estimated to be the most common sexually transmitted 
infection in the United States. However, there have been no data on the 
prevalence of HPV among women across a broad age range and representative of 
the U.S. population. High-risk HPV types can cause cervical, anal, and other 
genital cancers. High-risk HPV types are detected in 99 percent of cervical 
cancers, and worldwide approximately 70 percent of cervical cancers are due to 
HPV types 16 and 18, according to background information in the article. A 
highly effective vaccine against HPV types 6, 11, 16, and 18 was licensed in 
June 2006 and recommended for routine use in females age 11 to 12 years in the 
United States. Data on type-specific prevalence of HPV in the United States 
could help measure the effectiveness of the vaccine for reducing infection and 
could help evaluate its impact and cost effectiveness.

Eileen F. Dunne, M.D., M.P.H., of the Centers for Disease Control and 
Prevention (CDC), Atlanta, and colleagues estimated the prevaccine prevalence 
of HPV in the U.S. by performing HPV DNA testing on 2,026 self-collected 
vaginal swabs among females age 14 to 59 years participating in the National 
Health and Nutrition Examination Survey (NHANES) 2003-2004.

Of the 1,921 adequate specimens, 26.8 percent were positive for any HPV DNA. 
Using January 2004 population estimates and extrapolating this prevalence rate 
to the population, the authors estimate that approximately 24.9 million females 
in this age range have prevalent HPV infection. Prevalence of any HPV infection 
was highest among females age 20 to 24 years (44.8 percent); overall HPV 
prevalence among females age 14 to 24 years was 33.8 percent. This prevalence 
corresponds with 7.5 million females with HPV infection, which is higher than 
the previous estimate of 4.6 million HPV infections among females in this same 
age group in the United States.

There was a significant trend for increasing HPV prevalence with each year of 
age from 14 to 24 years, followed by a gradual decline in HPV prevalence 
through 59 years. Independent risk factors for HPV detection were age, marital 
status and increasing numbers of lifetime and recent sex partners.

Overall, HPV types 6, 11, 16, or 18 were detected in 3.4 percent of the study 
participants, corresponding with 3.1 million females with prevalent infection 
with HPV types included in the quadrivalent HPV vaccine.

"Our study provides the first national estimate of prevalent HPV infection 
among females aged 14 to 59 years in the United States," the authors write. 
"Our data indicate that the burden of prevalent HPV infection among women was 
higher than previous estimates."



http://www.sciencedaily.com/releases/2007/02/070227171051.htm