Submitted by Linda Schoene, Congregational Nurse
HPV (human papillomavirus) is receiving much media attention, especially with the announcement of the vaccine Gardasil. The messages conveyed are: (1) Cervical cancer is caused by HPV. (2) There is a vaccine to prevent HPV and therefore prevent cervical cancer. In reality, it is not quite that clear cut.
According to the CDC, approximately 20 million people in the US are infected with HPV. At least 50% of sexually active men and women will acquire genital HPV infection at some point in their lifetime. For most people, the infection clears on its own and causes no further problems.
Genital HPV is a sexually transmitted disease caused by the human papillomavirus.
HPV is actually a group of more than 100 strains or types of virus; 30+ of these
strains are sexually transmitted and can infect the genital area of both men
and women. Of these strains, some are high-risk and some are low-risk. High
risk strains can cause abnormal Pap tests and may also lead to genital cancers
in both men and women. The low-risk strains may cause mild Pap test abnormalities
and genital warts.
Most women are diagnosed with HPV on the basis of an abnormal Pap test, the
primary screening tool for cervical cancer. With proper follow-up, 90% of cervical
HPV infections become undetectable within 2 years. A small portion of women,
however, will have a persistent infection from a high-risk strain. This persistent
infection is the main risk factor for cevical cancer. No HPV tests are available
for men.
Regular Pap tests remain the best defense against HPV infection. The Pap test is a proven cancer screening test that has greatly reduced deaths from cervical cancer.
So what about the vaccine?
The FDA approved vaccine, Gardasil, offers protection against the 4 types of HPV that are responsible for 70% of cervical cancers and 90% of genital warts. The federal Advisory Committee on Immunization Practices recommends the vaccine for girls ages 11-12 and for girls/women 13-26 who have not received the complete vaccine series (3 injections over 6 months). The vaccine was studied in young women who were not exposed to any of the four HPV types and was found to be almost 100% effective in preventing precancers and genital warts caused by the 4 HPV strains. The vaccine was less effective in young women already exposed to the HPV strains and does not provide treatment for existing HPV infection, cervical cancer or genital warts.
In summary:
1. HPV has been identified as a significant risk factor for cervical cancer, but does not cause all cervical cancers.
2. With proper follow-up, most HPV infections clear on their own.
3. The vaccine Gardasil is effective in women never exposed to the four high risk HPV strains targeted by the vaccine.
4. Regular (generally once/year) Pap tests remain the best defense against cervical cancer. The majority of women diagnosed with cervical cancer have either never had a pap test or have not had one in the past five years.
Visit: www.cdc.gov/std/HPV/STDFact-HPV.htm for more information.