The recommendation that all 11-12 year old girls (as well as women up to 26
years of age) be immunized with HPV vaccine was an important public health
milestone. However, mandating this vaccine for school attendance raises a number
of unique social, ethical and moral questions. Before addressing these
questions, let’s consider some issues about
HPV infections and
vaccines as well as about
immunization mandates for school attendance.
1. Infection with HPV types that cause cancer. While some
HPV types are spread by casual contact, other types are acquired by intimate
sexual contact. These are known as genital HPV infections.
Genital HPVs cause cervical cancer—as well as other cancers and genital
warts.
- By 50 years of age, 70-80% of women will have acquired genital HPV
infection—often with more than one type of HPV. - Adolescents and young adults are very likely to acquire genital HPV
infection within a few months after beginning sexual activity. - A woman can also be infected with HPV by involuntary sexual
exposure—such as date rape—as well as by her husband (or partner) if he was
infected from a prior sexual partner, even if she were abstinent until
marriage. - Although the vast majority of women recover uneventfully from high-risk
(cancer causing) genital HPV infections, some of these infections may lead
to persistent infection, cause abnormal Pap tests, and progress to cervical
cancer. Regular Pap screening and then the treatment of any abnormalities
that are detected prevent many HPV infections from causing cervical cancer.
2. Vaccines against HPV. Two HPV vaccines have been under
development in the United States and
one of these was licensed in June 2006.
The new vaccines target HPV types 16 and 18, which cause about 70% of the
cases of cervical cancer. However:
- The vaccines do not protect a woman who is infected withe vaccine strain
of HPV infection before she is vaccinated—that is, vaccine needs to be
administered prior to exposure to the virus. - They do not protect against other high risk (cancer causing) strains not
in the vaccine—therefore, they will not eliminate all HPV-caused cancers.
Thus, screening and treatment programs will still be needed to reduce
cervical cancer deaths.
Because these vaccines prevent persistent genital HPV infections, they also
may have the potential to reduce the transmission of these particular
strains from person to person.
The vaccines appear to be very safe. Nevertheless, unexpected rare adverse
events may not be detected until after many more people have been immunized.
3. Vaccine recommendations and school mandates. The
individual states determine which vaccines should be required for school and
daycare entry based on the public health needs of the state, usually based upon
the Centers for Disease Control and Prevention (CDC) recommendations. States
require that school children be immunized against certain diseases to protect
bothe the vaccine recipient and his/her schoolmates from contagious illnesses.
State requirements differ.
- School mandates have increased immunization levels and have reduced
disease outbreaks, including among those who cannot receive the vaccine
because of medical reasons. - Most states permit religious and/or philosophical exemptions, in
addition to exemptions for medical contraindications. - Children who have been exempted from compulsory immunization for
religious or philosophical reasons are many times more likely to both
acquire and spread vaccine-preventable diseases.
4. Universal HPV immunization of school girls. The CDC has
made a
universal recommendation for girls 11-12 years of age to receive the HPV
vaccine (as well as older girls and women):
- A universal recommendation helps remove the social stigma associated
with receiving the HPV vaccine; that is, girls or women who receive the
vaccine should not be considered to be “more likely to engage in risky
sexual behavior” than their peers. - A universal recommendation makes the vaccine eligible for funding
through the
Vaccines For Children (VFC) program. In addition, any serious adverse
events associated with the vaccine can be addressed under the
Vaccine Injury Compensation Program.
Prevention of genital HPV infections
Avoiding HPV exposure. HPV infections are usually without
symptoms and can last for decades. For that reason, it is not possible to
accurately assess the risk of acquiring a genital HPV infection from any
specific sexual partner.
- Total sexual abstinence is logically the best protection against
acquiring all sexually transmitted infections, including genital HPVs.
However, it will not protect a woman against involuntary exposure such as
date rape and is not a very practical long term strategy. - Abstinence until marriage does not protect a woman if her husband is
infected from a prior sexual partner. - Monogamy by both sexual partners could possibly assure a woman’s
protection—but only if both partners have been abstinent and they remain
strictly monogamous.
Limiting HPV exposures.
Sexual behaviors are the most important risk factors for acquiring genital
HPV infection. Delaying sexual intercourse and limiting the number of sexual
partners could reduce the risk of HPV infection. But:
- More than 7% of high school students have their first sexual intercourse
before 13 years of age and 62% of girls and 70% of boys have had sexual
intercourse by the end of 12th grade. By ninth grade, almost 11% have had
more than four sex partners. - Consistent condom use may or may not provide some protection against
acquiring HPV—but condoms do protect against other sexually transmitted
infections, some of which may relate to whether her HPV infection progresses
to cervical cancer or not.
Preventive HPV Vaccines. The most effective strategy to
prevent HPV infection with the strains in the vaccine (which cause 70% of the
cases of cervical cancer) is to immunize women before they become infected. That
is why immunization is recommended for all girls at 11-12 years of age. However:
- The current HPV vaccines will not protect against other strains of HPV.
Thirty percent of cervical cancers are due to infection with strains not
included in the vaccine. - It is not yet known how long vaccine-induced immunity will last.
Compulsory HPV immunization. Mandating HPV immunization for
school entry would increase the proportion of girls and women who are
immunized—and therefore immune to the HPV types in the vaccine—before most of
them will be exposed. This is the most compelling argument in favor of mandating
this vaccine.
immunization laws are intended to control outbreaks of contagious diseases—such
as measles, diphtheria and others—that can spread easily to other school
children in the classroom. HPV is spread only by intimate sexual contact.
Costs of the vaccine. The vaccine is expensive (about $120 per
dose for the three shot series). To be most effective, a girl needs to
receive the entire 3 dose series, which requires three healthcare visits
(two more than is usual). The VFC and some health insurance plans cover the
costs of the 3 HPV vaccine doses and clinic visits. But not all families
have insurance, not all insurance plans cover HPV vaccine, and most children
are not VFC eligible.- Possible vaccine-associated disparities. Poorer women
are more likely to develop HPV infection and develop cervical cancer. If
poor women can not afford to get the vaccine, this disparity could become
greater. However, compulsory HPV vaccination could reduce the disease burden
disparity by assuring all socioeconomic groups of women obtain the vaccine.
Whether HPV immunization is compulsory or not, the cost of the vaccine will
keep some girls and women from receiving the vaccine.
Exemptions to compulsory immunization. Many parents and young
women who feel that laws requiring HPV immunization would conflict with
their beliefs and their personal liberties—or cost too much—would have a
means of opting out of compulsory HPV immunization. A possible, unintended,
adverse consequence then could be that people who opt out of HPV vaccine
might also opt out of other vaccines intended for this age group.
Could other mandates provide insight?
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Other Issues
Parental Concerns
Parental acceptance of HPV vaccines for their 11-12 year old daughters will
affect whether the vaccine is widely used in this age group. Most (75%) parents
in a recent
California study indicated that they would likely give their daughters the
HPV vaccine before the age of 13 years in order to keep their daughters safe.
However, 25% of parents have reservations about having their daughters immunized
at that age. The reasons they gave were their concern that vaccination might
influence their daughter’s sexual behaviors, their uneasiness about the morality
of immunizing to prevent sexually transmitted infections, and worries about the
safety of the vaccine.
- Will girls and women who receive the HPV vaccine be more likely
to engage in risky behavior? Preventing other sexually transmitted
infections such as HIV (the cause of AIDS), gonorrhea, genital herpes etc.
through abstinence and safe sex practices remains important for girls to
understand. It seems unlikely that a vaccine that prevents a small number
sexually transmitted infections which have no symptoms would cause girls to
be promiscuous or have unsafe sex, as some have suggested. However, there is
no evidence to support or refute this concern. - Potential adverse events from the HPV vaccine. Since
our experience with this new vaccine is limited and not all women are
exposed to high risk HPVs, some girls could experience rare vaccine adverse
events not yet identified without a corresponding benefit.
Will immunized women stop seeking cervical cancer screening programs?
Some have speculated that HPV-immunized women might not participate in cervical
cancer screening programs, thinking that they are not at risk anymore. The truth
is that they remain at risk for other high risk HPV infections and any
pre-existing HPV infection that they may have acquired prior to HPV
immunization. There is no evidence to support or refute this concern either.
Will universal HPV immunization reduce transmission of vaccine-strain
HPVs?
Although universal HPV vaccination may well reduce the transmission of the
vaccine type strains, there is no data that addresses this issue. However, it
seems unlikely that universal immunization of girls and young women would reduce
transmission, in the absence of an intervention to prevent transmission by and
to men. Data concerning the safety and effectiveness of the vaccine for boys and
men is being collected but is not available yet.
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