A Consumer Health Interactive Radio piece by Laurie Udesky

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In June 2006, the Food and Drug Administration approved a new vaccine that protects against the sexually transmitted germ known as human papilloma virus, or HPV. (Certain strains of HPV can cause cervical cancer.) To provide the most protection, the Advisory Committee on Immunization Practices recommends that girls be inoculated with the HPV vaccine before they are sexually active. Dr. Dean Blumberg* is a pediatric infectious disease specialist at the University of California at Davis Medical Center. I spoke with him about HPV, the safety of the vaccine, and what parents need to know in order to make an informed choice about vaccinating their daughters. I'm Laurie Udesky.

Udesky: The human papilloma virus, or HPV, is the most common sexually transmitted disease in the United States. According to the Centers for Disease Control and Prevention, there are 40 strains of HPV that are spread by genital contact, usually during vaginal or anal sex. Most HPV infections are harmless and go away on their own. But some types of HPV cause genital warts, and about 14 strains of HPV are associated with cervical cancer.

Half of all sexually active Americans will have HPV at some point in their life, but most of them won't even know it. That's because HPV is usually asymptomatic -- that is, there are no symptoms of the infection.

Dr. Dean Blumberg: Most infections with HPV are asymptomatic, and yet asymptomatic people can transmit the virus. During normal sexual activity it's common for micro-abrasions to occur and these micro-abrasions are basically small scratches. No bleeding occurs and they're not associated with pain, but they are small scratches due to friction during normal sexual activity. This allows the virus to gain access to the lower layers of the skin where infection then occurs.

Udesky: As in other sexually transmitted diseases, condoms may provide some protection against HPV. However, they don't prevent HPV transmission completely, explains Blumberg, because the virus can live in the genital area not protected by a condom. There are few realistic ways to protect against it.

Blumberg: One way to protect yourself against exposure to HPV is abstinence. Another possibility is mutual monogamy with somebody that has had no previous sexual partner.

Udesky: The HPV vaccine protects against four types of HPV.

Dr. Dean Blumberg: Two of these types are the most common causes of cervical cancer, and the other two types are the most common causes of genital warts.

Udesky: According to the CDC, the vaccine protects against the four strains of HPV that cause 70 percent of cervical cancers and 90 percent of genital warts.

The vaccine is recommended by the CDC for girls and women from ages 9 to 26, the age groups in which the vaccine was studied. The American Cancer Society has recommended that women in the 18- to 26-year old group consider the vaccine on a case by case basis because if they've already been exposed to the viruses, the benefits of the vaccine may be greatly diminished. Many states are considering making the HPV vaccine part of the inoculation schedule for 11- and 12-year-old girls. I asked Blumberg why it's recommended for girls that young.

Blumberg: This is a virus that is transmitted sexually, and the vaccine works only if it's given before someone's infected. So the most protection will be achieved if the vaccine is given before onset of sexual activity.

Udesky: Cervical cancer is rare in the United States due to regular screening for it through Pap tests. Early detection almost always leads to a good outcome, but the treatment can be painful. Getting inoculated, according to Blumberg, reduces the need for painful or invasive treatments.

Blumberg: With HPV, the treatment tends to be more physical, with lesions being burned away or surgically removed. It's a lot more involved [than treatments for many other sexually transmitted diseases].

Udesky: One significant concern is the vaccine's safety record. Blumberg says that studies done before the vaccine was approved show it to be safe:

Blumberg: The safety of the vaccine has been well studied in over 20,000 women, and several thousand of those [women] were in the 9- to 15-year-old age group. And increased reactions were not noted in the younger age group…There's nothing in the vaccine that would be [of concern], either in terms of theoretical reasons that would cause special reactions. So there have been no red flags out there in terms of the safety of the vaccine.

Udesky: Blumberg says that minor reactions, such as redness around the area where the shot was given and a slight fever that went away in a day or two, have been reported. Women who are pregnant should not get vaccinated. Blumberg also described two other possible scenarios in which someone should not get the vaccine:

Blumberg: If somebody has a dose of this vaccine and has a very severe reaction for some reason, then they should not receive another dose. It hasn't been reported, but if someone has been allergic to this vaccine -- the specific vaccine material -- then they shouldn't receive another dose. And then there's a very small amount of yeast product in the vaccine. So people who are exquisitely allergic to yeast should not receive the vaccine.

Udesky: Regardless of whether girls or women get the HPV vaccine, they still need to have regular Pap tests -- the procedure used to check for cervical cancer and pre-cancerous signs. This is because the vaccine does not protect against all cervical cancers. Also, while studies show that the vaccine provides protection for five years, it's not yet known how much longer than that it lasts.

Blumberg: I think we should do both, and make sure that everybody gets vaccinated. We make our screening programs more available and reliable and robust -- that's where we [can] have the biggest impact against this disease.

Udesky: The push for mandatory HPV vaccinations of pre-adolescent and teenage girls has caused a backlash among parents, many of whom do not want to vaccinate their daughters. Others are worried about safety issues. To be sure, some parents may hold off on vaccinating their daughters until wider use reinforces the safety suggested by the vaccine's pre-approval studies. Some states may require the vaccine for school entry, but most have "opt-out" clauses. As with all medical decisions, you should discuss the HPV vaccine with your doctor.

For Consumer Health Interactive, I'm Laurie Udesky

*Dr. Dean Blumberg is an uncompensated volunteer consultant to the California Medical Association Foundation’s expert panel on Cervical Cancer and HPV, which is funded by an unrestricted educational grant by Merck, the maker of the HPV vaccine Gardasil.

Copyright © 2007 Consumer Health Interactive