HPV Vaccination: Selling the Future When the Future is Unknown
What is known and what is as yet unknown about the current human papilloma virus (HPV) vaccination program, to prevent sexually acquired HPV stimulated cervical cancer, approved by the FDA in the United States, promoted by policymakers world wide and the couple of pharmaceutical companies who make the vaccine represents a scientific and ethical challenge. The program is for 12 year old pre-adolescent girls prior to becoming sexually active to be vaccinated and a catch up program for girls and women ages 13 through 18 up to 26 years of age. Unfortunately the effect of the vaccination program, because of the slow development of HVP stimulated cancer of the cervix will not be known for decades. The editorial written in the August 21, 2008 issue of the "New England Journal of Medicine" by C.J. Haug, discussing a research article in the same journal issue, sets the questions which I have provided as an extract below. Some of my visitors may not be familiar with all the terms but I think most will be understanding of the concern expressed.
The vaccine was highly successful in reducing the incidence of precancerous cervical lesions caused by HPV-16 and HPV-18, but a number of critical questions remained unanswered.5,6 For instance, will the vaccine ultimately prevent not only cervical lesions, but also cervical cancer and death? How long will protection conferred by the vaccine last? Since most HPV infections are easily cleared by the immune system, how will vaccination affect natural immunity against HPV, and with what implications? How will the vaccine affect preadolescent girls, given that the only trials conducted in this cohort have been on the immune response? The studies with clinical end points (i.e., CIN 2/3) involved 16- to 24-year-old women. How will vaccination affect screening practices? Since the vaccines protect against only two of the oncogenic strains of HPV, women must continue to be screened for cervical lesions. Vaccinated women may feel protected from cervical cancer and may be less likely than unvaccinated women to pursue screening. How will the vaccine affect other oncogenic strains of HPV? If HPV-16 and HPV-18 are effectively suppressed, will there be selective pressure on the remaining strains of HPV? Other strains may emerge as significant oncogenic serotypes.
Read the free full text at the link above and then return and perhaps write about your concerns, if any, regarding a large scale vaccination program where the answers regarding the overall benefit to countries where pap smear detection of pre-cancerous abnormalities with their early removal is commonplace. Does this vaccination program really promote benefit or will it simply encourage early sexual activity or in later years avoidance of necessary pap smear screening? ..Maurice.