Protection from HPV (Human Papillomavirus)

The human papillomaviruses (HPV) are a group of more than 100 related viruses, 40 of which infect the anal and genital areas. 15-20 types of these viruses are carcinogenic. Some types of HPV are referred to as “low-risk” viruses because they rarely cause lesions that develop into cancer. HPV types that are more likely to lead to the development of cancer are referred to as “high-risk.” Both high-risk and low-risk types of HPV can cause the growth of abnormal cells, but only the high-risk types of HPV lead to cancer. Sexually transmitted, high-risk HPVs include types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, and 73 (4). These high-risk types of HPV cause growths on the cervix that are usually flat and nearly invisible, as compared with the external warts caused by low-risk types HPV–6 and HPV–11. HPV types 16 and 18 together cause about 70 percent of cervical cancers (4, 5). It is important to note, however, that the great majority of high-risk HPV infections go away on their own and do not cause cancer.

HPV has been implicated in cancer of the cervix, vulva, vagina, anus, penis and oropharynx (tonsils and tongue). One hundred percent (100%) of cervical cancer cases worldwide (with almost 500,000 new cases and 270,000 deaths each year); 40% of vulvar and vaginal cases; 90% of anal cancer cases; 40% of penile cancer cases; 12% of oropharynx cancer cases; and 3% of mouth cancer cases can be attributed to cancer-causing HPV types.

HPV causes low-grade dysplasia (abnormal cell changes in cells lining the cervix), genital warts and recurrent respiratory papillomatosis (warty growths in the larynx of children and young adults which is caused by transmission of the HPV from a pregnant mother during childbirth). HPV is the most common sexually transmitted disease in the world right now.

The surest way to eliminate risk for genital HPV infection is abstinence or to refrain from any sexual contact with another individual. Note that sexual contact is not limited to penetrative sex alone but also includes any direct skin-to-skin contact such as oral sex, anal sex, or any other contact involving the genital area, including hand-to-genital contact. Avoid sharing of sex toys.


For those who choose to be sexually active, a long-term, mutually monogamous relationship with an uninfected partner is the strategy most likely to prevent genital HPV infection. However, it is difficult to determine whether a partner who has been sexually active in the past is currently infected.

HPV infection can occur in both male and female genital areas that are covered or protected by a latex condom, as well as in areas that are not covered. Although the degree of protection provided by condoms in preventing HPV infection is unknown, condom use has been associated with a lower rate of cervical cancer.

For women, it is advisable to undergo regular Pap tests. According to the American College of Obstetricians and Gynecologists (ACOG):

• Women should undergo a Pap test approximately 3 years after initiation of sexual intercourse (sexual debut) or at 21 years of age—whichever comes first.

• Women less than 30 years of age should undergo an annual Pap test.

• Women 30 years of age and older should undergo a Pap test every year. Those who have had 3 consecutive negative Pap tests may go for subsequent Pap tests every 2-3 years.

• Women who have had negative results in both Pap and HPV DNA tests should be re-screened no more frequently than every 3 years.

Having regular Pap test is one of the best ways to help protect against cervical cancer in the future. A Pap test can't diagnose HPV. But it can look for abnormal cells (that are caused by HPV) in the lining of the cervix before the cells become pre-cancers or cancer. For girls who are not old enough for a Pap test, regular wellness visits are a good way to start lifelong, healthy habits.

HPV vaccines are now available for both males and females to protect against the types of HPV that most commonly cause health problems. The HPV vaccine is a prophylactic vaccine which stimulates the body’s immune system to produce neutralizing antibodies that kill HPV in the skin cells of a man or woman’s genital area. That’s why it’s best to get vaccinated at a young age when the immune system is at its strongest and therefore will mount a robust antibody response to the vaccine. Early vaccination is also ideal because sexual debut is unlikely at this age. As early as age 9 for both girls and boys. Catch-up vaccination is for any woman who was vaccinated after she has had sex, regardless of age.

What about women who are already sexually active? “They may still benefit from vaccination because even if a woman has been exposed to HPV, it's unlikely that she has been exposed to all virus types covered by the HPV vaccine. So the vaccine could still help protect against HPV types the woman hasn't been exposed to,” a PGH OB-GYN specialist explains.

There are currently two available HPV vaccines. The bivalent vaccine (Cervarix) helps protect against two HPV types 16 and 18, while the quadrivalent type (Gardasil)helps protect against four HPV types 6, 11, 16 and 18. HPV 16 and 18 cause 70% of cervical cancer cases while HPV 6 and 11 cause 90% of genital warts cases. “The bivalent vaccine protects against cervical cancer whereas the quadrivalent vaccine protects against cervical cancer, plus genital warts (which is one of the most prevalent sexually-transmitted infections in the world), vaginal cancer, and vulvar cancer,” Dr. Domingo notes. Recently, Gardasil has been approved by the FDA for use in males aged 9 to 26 years of age to prevent genital warts caused by certain types of HPV.

Both HPV vaccines have excellent safety and tolerability profiles. Minor adverse reactions, such as pain, redness and swelling, are limited to the injection site. No major adverse events have been reported. The vaccination schedule for both vaccines involves three doses administered intramuscularly within 6 months. For the bivalent vaccine, the schedule is day 1, month 1 and month 6. For the quadrivalent vaccine, the schedule is day 1, month 2 and month 6.

Please consult your physician for further medical information about HPV and HPV vaccines.