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Which HPV types are included in tetravalent HPV vaccines?

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Infographic showing estimated lives saved by childhood vaccinations worldwide from 1974 to 2024, with syringe-shaped bars for each disease. Measles tops the list at 93.71 million lives saved, followed by tetanus, whooping cough, and others, for a total of 153.84 million lives saved. — vaccine Vaccines and the estimates of lives saved over the period 1974–2024.

Tetravalent (or quadrivalent) HPV vaccines, such as the original Gardasil, are designed to protect against four specific types of human papillomavirus: HPV-6, HPV-11, HPV-16, and HPV-18.12

These types are categorized based on their associated health risks:
* HPV-6 and HPV-11: These are considered low-risk strains and are responsible for approximately 90 percent of sexually transmitted genital warts.23
* HPV-16 and HPV-18: These are high-risk strains linked to the majority of cervical cancers, as well as other cancers of the genital tract.23

While newer vaccines like Gardasil 9 have been developed to provide broader protection against nine HPV types, the original tetravalent formulation specifically targets these four strains to reduce the incidence of both benign warts and malignant disease.12