Study: 'Opt-out' option key to support of mandatory HPV vaccination
- Sexually-transmitted disease human papillomavirus (HPV) is one of the causes behind the majority of cases of cervical cancer, as well as genital warts and a whole collection of other cancers. The two available vaccines, market leader Gardasil from Merck and GlaxoSmithKline’s Cervarix, can protect against the most important types of the virus.
- Requiring vaccination on school entry could prevent many of these cases of cancer, but most parents only support this idea if an opt-out option is provided, according to a new study.
- Gardasil is one of Merck's top-selling products, pulling in nearly $2 billion dollars in sales last year. But the vaccines have seen some opposition, partly driven by moral and religious beliefs.
HPV can increase the risk of a number of cancers, most notably cervical cancer. Market leader Merck & Co’s Gardasil vaccine (also known as Gardisil or Silgard) prevents infection with HPV types 6, 11, 16 and 18.
These strains are behind about 70% of the cases of cervical cancer, most cases of genital warts, and the majority of anal, vulvar, vaginal and penile HPV-induced cancers. They are also linked with more than half of the cases of oropharyngeal cancers in the US. Cervarix, from GlaxoSmithKline, protects against HPV types 16 and 18.
So, it would seem like a clear case for a vaccine. Vaccinate children before they are sexually active, prevent infection and therefore cut the risk of a collection of different cancers.
Merck has been successful in selling Gardasil in the U.S. and other countries. But HPV vaccinations have also run into some of the same opposition faced by other vaccines, partly as a result of opposition from anti-vaccine politicians and from those who oppose the vaccine on moral or religious grounds.
Still, coverage is growing. The Centers for Disease Control and Prevention (CDC) reported that around 40% of adolescent girls in the U.S. had all three doses of the HPV vaccine in 2014, compared with 38% in 2013. The figures for adolescent boys were 22% in 2014, rising from 13% in 2013.
Higher levels could be achieved by requiring vaccination for school entry. In a national study carried out by researchers at the University of North Carolina at Chapel Hill, 21% of parents of children aged 11 to 17 agreed a law requiring HPV vaccination for school attendance would be a good idea. Perhaps counter-intuitively, the number of parents thinking the law would be a good idea almost tripled to 57% if there was an opt-out option included.
"School entry requirements are highly acceptable to parents, but only when implemented in a way that makes them ineffective," said senior study author Noel Brewer. "Opt-outs lead to a large number of parents choosing not to vaccinate their children, and that makes requirements ineffective in raising vaccination rates."
Given these results, the researchers suggest only considering requirements for vaccines following implementation of other approaches, such as physician training and vaccination reminder programs.
- ABC News Parents Want 'Opt-Out' Option for HPV Vaccine, Study Finds
- American Association of Cancer Research Study
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