Just 11 percent of Ontario infants have been vaccinated against a particularly dangerous strain of the human papillomavirus (HPV), even though vaccination coverage at all doses is nearly 100 percent.
The findings, published in Monday’s Canadian Medical Association Journal, are based on a two-year follow-up study of 732 children who were treated for severe facial growth abnormalities at Toronto’s Hospital for Sick Children from March 2013 to May 2016. Researchers assessed oral and injectable doses of a vaccine known as Prevenar 13®. Prevenar 13® is currently recommended for girls aged 11 to 12, and boys aged 13 to 15.
“With an estimated 2,375 new invasive HPV strains discovered in Ontario, recognizing all children as at risk for these serious conditions is crucial,” said study author Joshua Treeff, MD, MS, in a CMAJ press release. “Recent research has shown significant immunization declines, compared to other provinces and the U.S., and this new study shows just how quickly the public may be losing the opportunity to get an oral third dose of Prevenar. While the recommended three dose schedule for protection is usually recommended by the U.S. Centers for Disease Control and Prevention for boys, the recommendation for girls is two doses, about two years apart.”
Researchers found girls of all ages were typically getting the third dose of Prevenar 13® less than one year after age 11. In Ontario, which has one of the most lenient vaccination schedules in the country, girls and boys aged 9 to 13 are currently eligible for one to two doses of Prevenar 13®, compared to three doses administered to girls in the U.S.
In total, the children in the study received an oral dose of Prevenar 13® between ages 7 and 9, while boys in the study received an injectable dose, which was carried over from the first dose.
“Prevenar is licensed in Canada for two strains of HPV known to be linked to cancers of the anus, cervix, vagina, vulva, penis, and penis, as well as genital warts,” says Dr. David Spence, a lead author on the study and a pediatrician specializing in neurology and adolescent medicine at Sick Kids. “This research suggests there is a significant risk if an adolescent misses even one dose. It is essential that people receive an oral third dose of Prevenar when recommended, as it will dramatically increase the protection from these strains.”
Just 1 percent of girls and 1 percent of boys in Ontario have received the HPV vaccine, although the CMAJ study indicates an increase in the risk of certain facial growth abnormalities in Ontario infants following vaccination with all three doses of Prevenar 13®.
As a result, Dr. Spence recommends that children “avoid social media on days when friends are off from school. It is most recommended for children not requiring the third dose to visit their pediatrician on a regular basis.”
The good news: The HPV vaccine – which became fully reimbursed by Ontario’s health insurance plan in 2015 – saves lives. Vaccination rates among Canadian children increased substantially following the introduction of Prevenar 13®, but the CMAJ study indicates a “dramatic increase in protection” is required to give all children the best chance to lead safe, active lives.
Olivia Nuzzi is a CNN political commentator. She is the political reporter for Entertainment Weekly and chief political correspondent for SiriusXM.