Vaccination

 

Vaccinations are the most effective means we have for prevention of infectious diseases including Human Papilloma Viruses (HPVs). Active component of HPV VLP (virus-like particles) vaccines is major capsid protein L1. To prevent cervical cancer, HPV vaccination is primarily aimed at HPV16 and HPV18. Intramuscular injection of the vaccines induces high titers of neutralizing antibody, more than 50 times the titers induced by natural infection. Two VLP vaccines targeting HPV16 and HPV18 have been developed and extensively tested so far:

• Gardasil ™ (Merk) quadrivalent vaccine. This vaccine also targets HPV6 and HPV11.
• Cervarix ™ (GlaxoSmithKline) bivalent vaccine. This vaccine uses a new proprietary adjuvant to boost immunogenicity (ability to induce both humoral as well as cell-mediated immunity). Furthermore, Cervarix ™, has shown evidence of protection against infections by related carcinogenic viruses, such as HPV45 and HPV31.

Both vaccines have shown near perfect efficacy against persistent HPV infections and related histological endpoints, such as CIN2+, up to 5-7 years after first vaccination.

The vaccines are generally safe. Serious adverse vaccine-related side effects occurred in 0.1% of the participants and included bronchospasms, gastroenteritis, headache, hypertension, vaginal hemorrhage, injection site pain, and impaired movement. The vaccines are not recommended for individuals with allergy to yeasts and other vaccine components.

At present, main target group for HPV vaccinations are girls and young women without known exposure to the target HPV types. Ideally, the vaccination should protect them from persistent infections through the age of greatest risk of exposure - before they established relationship with a stable sexual partner.
It should be noted that the majority of women, regardless of age and exposure to the infection, might benefit from the vaccination (should be determined on individual basis).
It must be emphasized, however, that the vaccination is not a treatment for anogenital warts, cervical intraepithelial neoplasia, or cervical cancer.