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COSTA RICA
HPV
Vaccine Provides Little Benefit for Older
Women
Researchers from Costa Rica have reported
that women over the age of 40 are not likely
to benefit from vaccination to prevent human
papillomavirus (HPV). The details of this
study were published in the March 3, 2010
issue of the Journal of the National Cancer
Institute.
Human papillomaviruses consist of more than
100 different viruses. Some types of HPV
cause warts on the hands or feet; others
cause genital warts; and some have been
linked with cancer, most notably cervical
cancer. The types of HPV most commonly
linked with cervical cancer are HPV16 and
HPV18, but several other high-risk types
contribute to cancer as well.
The types of HPV that cause cervical cancer
or genital warts are transmitted sexually.
HPV infection is extremely common and
generally occurs soon after an individual
becomes sexually active. Although most
infections resolve on their own, some
persist and can lead to precancerous or
cancerous changes to the cervix, vulva,
vagina, penis, and anus. HPV infection has
also been linked to certain cancers of the
head and neck.
Recognition of the link between HPV and
cervical cancer led to the development of
vaccines designed to prevent infection with
certain high-risk types of HPV.
Currently, there are two vaccines approved
for the prevention of HPV 16 and 18:
Gardasil® and Cervarix®. Gardasil also
protects against HPV 6 and 11, which are
associated with most types of genital warts.
The vaccines are recommended for girls as
young as age 9 and up to age 26. It is
generally agreed that vaccination of older
women would be of little benefit. A previous
study conducted by the Researchers from the
Harvard School of Public Health reported
that HPV vaccination for prevention of
cervical cancer is not cost-effective in
women between the ages of 35 and 45 years.
A study of more than 9,000 Costa Rican women
ages 19 to 97 evaluated the patterns of HPV
infection as women age. These researchers
found that the rate of newly detected
infections declined with age—from 35% in
women ages 18-25 to 13.5% in women over the
age of 42. In both younger and older women,
new infections typically cleared up without
treatment within two years. They found that
new infections typically did not progress to
worse disease in older women.
Based on their findings, the researchers
concluded that HPV vaccination was not
likely to be beneficial for older women. The
vaccinations are used to prevent new
infections, and older women are not getting
many new infections.
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