July 2 (UPI) -- A large number of human papillomavirus cases could be wiped out in California -- and prevent thousands of cases of cancer -- if the state adopted widespread vaccination, a new study says.
A vaccination coverage rate of 99.5 percent would prevent more than 1,300 people in the state from developing cervical cancer because of the reduction in HPV infection rates, according to a new study published Monday in the journal Sexually Transmitted Diseases.
The new research follows studies in recent weeks that have shown HPV vaccination is contributing to significant decreases in the prevalence of HPV strains known to cause cervical and other cancers.
Up to 90 percent of sexually active people are likely to be infected by HPV at some point in their lives. The infection can lead to cervical cancer, as well as anal, vaginal, penile and throat cancers.
Researchers, experts and leaders are now suggesting an expansion of vaccination, including some women and men receiving it up to age 45 -- with the new California study suggesting there are benefits to wider vaccine coverage.
"An increase in California's HPV vaccination rate would reduce the number of preventable cancers and the financial burden that treatment for these cases would put on the health care system," the authors of the new study, among them researchers from the University of California Los Angeles, University of Texas and Cornell University, said in a press release.
For the study, researchers looked at 2017 vaccination coverage rates of boys and girls in California, and estimated the HPV-related cancer strains in the group. In California, nearly 61 percent of teen girls and more than 46 percent of teen boys received vaccinations in 2017.
The researchers compared the cancer cases from the 2017 group vaccination group with the optimal vaccination rate of 99.5 percent.
Not having the teens vaccinated would cost an estimated $52.2 million to the California health care system over time, the researchers say.
The HPV vaccine comes in two doses. The Centers for Disease Control and Prevention recommends children get the first dose between ages 11 and 12, and the second dose six months to a year after.
During the two-day annual meeting of the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices last month, experts discussed the potential of expanding vaccination, voting to recommend that people up to age 45 get an HPV shot.
The World Health Organization has also said that by ramping up vaccinations, screenings and treatment worldwide, HPV could be eradicated.
A Lancet study published in June examined the possibility and impact of increasing those efforts. It said older people who wouldn't benefit from the HPV vaccine would need to be screened and treated for cervical cancer, a result of HPV infection in women.
If the scaled-up vaccinations, examinations and treatments began in 2020, it could prevent up to 13.4 million global cases of cervical cancer by 2069. Otherwise, the researchers estimated that more than 44 million women worldwide will be diagnosed with cervical cancer in the next 50 years.
"Widespread coverage of both HPV vaccination and cervical screening from 2020 onwards has the potential to avert up to 12.5-13.4 million cervical cancer cases by 2069, and could achieve average cervical cancer incidence of around four per 100,000 women per year or less ... by the end of the century," authors wrote in the WHO-funded study.