Human Papillomavirus (HPV)
National Physicians Center for Family Resources
Human Papillomavirus infection is common, highly contagious, and spread through skin-to-skin contact as well as through sexual contact. An estimated 20 million people, including about one-third of all sexually active teenagers, have HPV. Those who have more than three or four sexual partners, means it is virtually impossible to avoid becoming infected. In addition, it is still possible to be contagious even when warts are not visible.
Some medical experts have suggested that the biggest toll HPV takes is probably psychological. However, they also acknowledge that, “in rare cases, these HPV types can cause cancer of the cervix, vulva or vagina.
Unfortunately, for our adolescents today, that is not the entire truth. We do know that over 99% of all cervical cancers are associated with HPV infections, and the rates of cervical cancers in women younger than 50 years of age are increasing dramatically. We also know that cancerous lesions of the cervix take at least 10 to 15 years to develop. Since there are over 120 types of HPV, each with a different virulence and cancer causing capability, the natural history of the virus is difficult to study. One longitudinal study of adolescents did demonstrate that 90% of low risk type HPV infections were spontaneously eradicated over a 30 month period of time, while only 70% of high-risk type HPV infections were eradicated. However, for those teens who have persistent infection, there is 14 fold increased risk for development of precancerous cervical lesions.
At this point in time, it is not known which factors contribute to persistence of HPV infection – BUT we do know that adolescents are at increased risk because of the cellular changes which are taking place on the cervix during puberty.
- La Vecchia, et al, showed that young age at first intercourse was “strongly associated with a risk for invasive cancer.” Women who reported having had their first intercourse before age 18 years were at a five-fold increased risk as compared with women who waited until after age 22 years. (Cancer 1986; 58: 935-941)
- Wright ad Roipelle demonstrated that for girls who had their first intercourse between 10 and 14 years of age, the mean age for developing HSIL (high grade squamous intra-epithelial lesions) was 25 years. In comparison, women who began sexual involvement after age 20 years did not develop HSIL until a mean age of 37 years. (Am J Obstet Gynecology 1984; 149: 824-830)
- In the study by Andersson-Ellstrom, et al, NONE of the sexually inexperienced girls was found to be seropositive for HPV infection. (Sexually Transmitted Diseases 1996; 23: 234—238)
HHPV infection has also been associated with development of cancers of the vagina, vulva, anus, male urethra and penis. Young men are less likely to have symptoms and are therefore more likely to transmit the virus without realizing it. Most physicians do not routinely screen partners of infected women, making the identification of the HPV infected male even less likely. Unfortunately, HPV has been associated with the much later development of cancer of the penis.
In a rare instance, an HPV infected mother can transmit the virus to her infant. The HPV virus in the infant may cause laryngeal papillomatosis, a disorder in which polyps develop on the vocal cords. This causes severe respiratory distress in the infant and must be treated by repeated surgical excision or laser therapy.
To summarize, HPV infection is a serious public health concern because the virus is:
- highly contagious, being transmitted through close skin-to-skin contact as well as sexual intercourse
- prevalent in our society, and present in most individuals who have had 3-4 sexual partners
- caused by numerous types, many if not most cause symptoms (Only 1-2% of these types cause genital warts, the remainder of infected individuals have no symptoms.)
- difficult to diagnose in the asymptomatic female as there is not one easy and accurate test to check for HPV infection
- difficult to diagnose in the asymptomatic male who is most likely to transmit the infection – but for whom there is no treatment
- the cause of over 99% of cervical cancers – the rates of which are increasing, especially in women less than 50 years of age
- implicated in the development of cancers of the vagina, vulva, anus, and male urethra and penis
- most often diagnosed in women by cellular changes in the Pap smear which is usually done just once a year (Adolescents again are at an increased risk since sexually active female teens do not always have annual Pap smears.)
- often undiagnosed on Pap smear – with some studies demonstrating a 20–40% false negative rate
- variable in its infectivity, with some studies demonstrating 70–90% of women becoming symptom free after 1–2 years
- persistent in some women, causing cellular changes on the cervix which represent precancerous lesions
- a more serious infection in adolescent females who are more likely to have a persistent infection, with a subsequently higher rate of precancerous and cancerous lesions
- often a cause of latent disease – with clinical disease not being evident for 10–15 years after initial infection
- rarely able to infect a newborn infant
- HPV is not reportable to the Centers for Disease Control and Prevention
- preventable – through sexual abstinence
In addition, the treatment of genital warts is often not simple and easy. Topical medications such as Podofilox and Imiquimod must be applied repeatedly. Podophyllin must be used weekly for up to six weeks, while Podofilox is used twice daily for three consecutive days, and then repeated weekly for up to 4 weeks. Both topical treatments have a cure rate of approximately 40% with a recurrence rate of 20-30%. In addition, patients often experience adverse reactions of burning and itching. Other treatments, such as Trichloroacetic acid (TCA) and cryotherapy can cause ulcerations and erosions, as well as burning and pain. Many of the more expensive treatments, such as laser therapy, may not be available to the patient or may not be covered by the patient's insurance.
The treatment of HPV when the cervix is infected may require only local topical treatment, or may require surgical excision of the affected area. This “conization: of the cervix may cause later difficulty with carrying a pregnancy to term.
These are all serious health concerns, which should be presented honestly and accurately when giving medical information to adolescents. It is important to note that there is now a vaccine against the two most common types of HPV that cause cervical cancer. The vaccine Gardicil, is currently offered to adolescent young women by pediatricians.
However, given the high rates of infection in our population, the highly contagious aspects of the HPV infection, the inability for condoms to provide adequate protection from this infection, and the increased risk of cervical cancer associated with some forms of HPV infection, it seems medically prudent to advise adolescents to delay sexual activity until they are married in a monogamous relationship. They will thus be able to live their lives free from the above concerns.
R. Bob Mullins, MD
Family Medicine, Valley, Alabama
Hal Wallis, MD
Obstetrics-Gynecology, Dallas, Texas
Jane E. Anderson, MD
Pediatrics, San Francisco, California
Glen C. Griffin, MD
Pediatrics, Mapleton, Utah