Muchas madres están preocupadas por la posible vacunación de sus hijas para prevenir el cáncer de cuello uterino. Pero no tienen claro las ventajas e inconvenientes. La mayoría de profesionales recomiendan su aplicación a las niñas de 11 ó 12 años.
Merck ha lanzado una campaña promocionando su vacuna Gardasil, señalando a una mujer jóven y diciendo que puede ser una menos en sufrir el citado cáncer. Esta propaganda ha captado la atención de los padres. En menos de dos años más de 8 millones de jovenes han recibido la vacuna. El Dr. Nathan Litman, Director de Pediatría en el Montefiore Medical Center de New York, considera que Gardasil es un notable avance médico. Sin embargo, un editorial de la revista New England Journal of Medicine's Editorial realiza varias cautelas sobre la misma. En primer lugar, no está claro su beneficio a largo plazo dado que el cáncer tarda años en desarrollarse, y la información disponible no determina si la vacuna funciona. En segundo lugar, el efecto global de la vacuna sobre el cáncer cervical sigue siendo desconocido. Además, el impacto de la vacunación no se detectará hasta dentro de unas décadas. El precio de Gardasil es muy alto y no se sabe si serán necesarias otras dosis posteriores.
No se puede dejar de mencionar que Gardasil protege solo frente a ciertos tipos de virus del papiloma, será necesario continuar con el screening citológico, y algunos médicos consideran que la citología es más segura que la vacunación.
Jane J. Kim, Ph.D., and Sue J. Goldie, M.D.
Health and Economic Implications of HPV Vaccination in the United States
ABSTRACT
Background The cost-effectiveness of prophylactic vaccination against human papillomavirus types 16 (HPV-16) and 18 (HPV-18) is an important consideration for guidelines for immunization in the United States.
Methods We synthesized epidemiologic and demographic data using models of HPV-16 and HPV-18 transmission and cervical carcinogenesis to compare the health and economic outcomes of vaccinating preadolescent girls (at 12 years of age) and vaccinating older girls and women in catch-up programs (to 18, 21, or 26 years of age). We examined the health benefits of averting other HPV-16–related and HPV-18–related cancers, the prevention of HPV-6–related and HPV-11–related genital warts and juvenile-onset recurrent respiratory papillomatosis by means of the quadrivalent vaccine, the duration of immunity, and future screening practices.
Results On the assumption that the vaccine provided lifelong immunity, the cost-effectiveness ratio of vaccination of 12-year-old girls was $43,600 per quality-adjusted life-year (QALY) gained, as compared with the current screening practice. Under baseline assumptions, the cost-effectiveness ratio for extending a temporary catch-up program for girls to 18 years of age was $97,300 per QALY; the cost of extending vaccination of girls and women to the age of 21 years was $120,400 per QALY, and the cost for extension to the age of 26 years was $152,700 per QALY. The results were sensitive to the duration of vaccine-induced immunity; if immunity waned after 10 years, the cost of vaccination of preadolescent girls exceeded $140,000 per QALY, and catch-up strategies were less cost-effective than screening alone. The cost-effectiveness ratios for vaccination strategies were more favorable if the benefits of averting other health conditions were included or if screening was delayed and performed at less frequent intervals and with more sensitive tests; they were less favorable if vaccinated girls were preferentially screened more frequently in adulthood.
Conclusions The cost-effectiveness of HPV vaccination will depend on the duration of vaccine immunity and will be optimized by achieving high coverage in preadolescent girls, targeting initial catch-up efforts to women up to 18 or 21 years of age, and revising screening policies.
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Sanofi-Pasteur MSD ha anunciado que se están realizando ensayos clínicos para valorar la eficacia en hombres de la vacuna tetravalente contra VPH. Con ello se pretende reducir los cánceres genitales masculinos y el riesgo de contagiar el VPH a las mujeres heterosexuales y a otros varones homosexuales. ...
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El cáncer de cuello uterino es el resultado de una infección prolongada por VPH de alto riesgo para desarrollar cáncer, en el varón y en la mujer, en la región genital externa e interna.
El Dr. Bosch, un lider de opinión mundal, del Instituto Catalán de Oncología ha analizado la epidemiología de la infección por el VPH en un reciente artículo. La enfermedad cancerosas solo aparece tras una infección causada por algunos de los tipos de VPH. El virus se ha demostrado en el cáncer escamoso y en el adenocarcinoma, y en las lesiones precursoras del cáncer (SIL/CIN). Los cofactores que modifican la evolución incluyen los contraceptivos hormonales, tener muchos hijos, y haber sufrido otras enfermedades infecciosas de transmisión sexual como clamidia tracomatis, herpes simple tipo 2, y fumar intensamente.
Dis Markers. 2007;23(4):213-27. Related Articles
The epidemiology of human papillomavirus infection and cervical cancer.
Bosch FX, de Sanjosé S.
Institut Català d'Oncologia, Epidemiology and Cancer Registration Unit, E-08907 L'Hospitalet de Llobregat, Barcelona, Spain.
Cervical cancer has been recognized as a rare outcome of a common Sexually Transmitted Infection (STI). The etiologic association is restricted to a limited number of viral types of the family of the Human Papillomaviruses (HPVs). The association is causal in nature and under optimal testing systems, HPV DNA can be identified in all specimens of invasive cervical cancer. As a consequence, it has been claimed that HPV infection is a necessary cause of cervical cancer. The evidence is consistent worldwide and implies both the Squamous Cell Carcinomas (SCC), the adenocarcinomas and the vast majority (i.e. > 95%) of the immediate precursors, namely High Grade Squamous Intraepithelial Lesions (HSIL)/Cervical Intraepithelial Neoplasia 3 (CIN3)/Carcinoma in situ. Co-factors that modify the risk among HPV DNA positive women include the use of oral contraceptives (OC) for five or more years, smoking, high parity (five or more full term pregnancies) and previous exposure to other sexually transmitted diseases such as Chlamydia Trachomatis (CT) and Herpes Simplex Virus type 2 (HSV-2). Women exposed to the Human Immunodeficiency Virus (HIV) are at high risk for HPV infection, HPV DNA persistency and progression of HPV lesions to cervical cancer.
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Una de cada 4 mujeres norteamericanas de 14 a 59 está infectada por el virus del papiloma humano (VPH), según una encuesta recintemente publicada. La Dra. Eileen Dunne coordinadora del estudio ha llamado la atención sobre el problema. Muchas de esas mujeres van a desarrollar alteraciones celulares (incluso cáncer de cuello uterino o de vulva) y condilomas genitales. El VPH también produce cáncer de pene y de ano.
Partículas de VPH (Izquierda), condilomas vulvares (centro) y condilomas de pene (derecha).
¿Cual es la situación en España? No hay datos fidedignos, pero es alarmante por el alto grado de promiscuidad sexual entre la juventud y, sobre todo, por no hacer uso correcto del condón. El tiempo que tarda en aparecer el cáncer es muy variable, llegando a tardar hasta 10 años. En la encuesta norteamericana la mayor tasa de infecciones corresponde a la edad 20-24 años.
Dr. P
| JAMA. 2007 Feb 28;297(8):813-9. |
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Prevalence of HPV infection among females in the United States.
Dunne EF, Unger ER, Sternberg M, McQuillan G, Swan DC, Patel SS, Markowitz LE.
Centers for Disease Control and Prevention, Atlanta, Ga 30333, USA. dde9@cdc.gov
CONTEXT: Human papillomavirus (HPV) infection is estimated to be the most common sexually transmitted infection. Baseline population prevalence data for HPV infection in the United States before widespread availability of a prophylactic HPV vaccine would be useful. OBJECTIVE: To determine the prevalence of HPV among females in the United States. DESIGN, SETTING, AND PARTICIPANTS: The National Health and Nutrition Examination Survey (NHANES) uses a representative sample of the US noninstitutionalized civilian population. Females aged 14 to 59 years who were interviewed at home for NHANES 2003-2004 were examined in a mobile examination center and provided a self-collected vaginal swab specimen. Swabs were analyzed for HPV DNA by L1 consensus polymerase chain reaction followed by type-specific hybridization. Demographic and sexual behavior information was obtained from all participants. MAIN OUTCOME MEASURES: HPV prevalence by polymerase chain reaction. RESULTS: The overall HPV prevalence was 26.8% (95% confidence interval [CI], 23.3%-30.9%) among US females aged 14 to 59 years (n = 1921). HPV prevalence was 24.5% (95% CI, 19.6%-30.5%) among females aged 14 to 19 years, 44.8% (95% CI, 36.3%-55.3%) among women aged 20 to 24 years, 27.4% (95% CI, 21.9%-34.2%) among women aged 25 to 29 years, 27.5% (95% CI, 20.8%-36.4%) among women aged 30 to 39 years, 25.2% (95% CI, 19.7%-32.2%) among women aged 40 to 49 years, and 19.6% (95% CI, 14.3%-26.8%) among women aged 50 to 59 years. There was a statistically significant trend for increasing HPV prevalence with each year of age from 14 to 24 years (P<.001), followed by a gradual decline in prevalence through 59 years (P = .06). HPV vaccine types 6 and 11 (low-risk types) and 16 and 18 (high-risk types) were detected in 3.4% of female participants; HPV-6 was detected in 1.3% (95% CI, 0.8%-2.3%), HPV-11 in 0.1% (95% CI, 0.03%-0.3%), HPV-16 in 1.5% (95% CI, 0.9%-2.6%), and HPV-18 in 0.8% (95% CI, 0.4%-1.5%) of female participants. Independent risk factors for HPV detection were age, marital status, and increasing numbers of lifetime and recent sex partners. CONCLUSIONS: HPV is common among females in the United States. Our data indicate that the burden of prevalent HPV infection among females was greater than previous estimates and was highest among those aged 20 to 24 years. However, the prevalence of HPV vaccine types was relatively low.
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La salud de la mujer / Woman's Health
menopausia climaterio
salud de la mujer
women's health
ginecologia
health
