Now a new study in Britain of an early version of the vaccine found that within 13 years of vaccine administration, there were 87 percent fewer cases of cervical cancer among young women immunized between ages 12 and 13, compared to unvaccinated women. Significantly lower cancer rates were also found among women immunized between ages 14 and 16 and between 16 and 18, although the greatest benefit occurred among those vaccinated at the youngest ages, before most girls were likely exposed to the virus through sexual contact.
The British study involved a vaccine called Cervarix, that protects against two variants of the virus. The current American version of the HPV vaccine, called Gardasil-9, is even more effective: It protects against nine variants of the virus and is expected to prevent more than 90 percent of HPV-related cancers, Dr. Aragones said. A recent analysis in JAMA Pediatrics found a similar decrease in cervical cancer incidence and mortality in young women since the vaccine was introduced.
Based on a steadily declining incidence of cervical cancer and a high rate of vaccine coverage in Australia, researchers there predicted that the country would have fewer than four new cases of cervical cancer per 100,000 women by 2028 and virtually none by 2066.
To be sure, regular Pap smears that detect precancerous cervical lesions have helped greatly to prevent the development of invasive cancer, but early detection efforts do not fully eliminate the risk of cervical cancer. This year, the American Cancer Society estimates that 14,480 new cases of invasive cervical cancer will be diagnosed in the United States and about 4,290 women will die from it. And there is no screening test like the Pap smear for the other five HPV-caused cancers.
Parents’ buy-in remains the biggest obstacle
Once the real cancer culprit was identified as the human papillomavirus and a vaccine to prevent it finally developed, convincing parents to have their young daughters immunized has been an uphill battle for practitioners. Few have the time and factual ammunition to counter parental fears and misinformation about this vaccine.
Getting parents to agree to immunizing boys has faced an additional obstacle. The original approval of the vaccine to prevent cervical cancer prompted many parents to question its value for boys, for whom the vaccine was approved three years later. Parental resistance to immunizing their sons rose to 59.2 percent in 2018, up from 44.4 percent just six years earlier
“Parents and providers don’t necessarily appreciate the burden of HPV-caused cancers among men,” said Dr. Dean A. Blumberg, chief of pediatrics at UC Davis Children’s Hospital. “Oral-pharyngeal cancer rates are almost five times higher in men than in women, and they’ve increased in recent years with the rise in oral sex. The vaccine is important for the boys to protect their own health and the health of their future partners.”
