Improved HPV vaccine protects against 9 types of the virus


Andrea Cannon

HPV Vaccine

By Associate Editor

In an effort to reduce sexually transmitted infections among young people, scientists in London have developed a new human papilloma virus vaccine that inoculates people against nine strains of the virus.

HPV is a sexually transmitted infection that can lead to cancer, and although there are two HPV vaccines available, Gardasil and Cervarix, they only protect individuals from 70 percent of all cervical cancers—types 16 and 18. Like prior vaccines, the new vaccine Gardasil 9 is administered by three injections during a period of six months. Trials suggest that the vaccine protects individuals against 90 percent of cervical cancers, according to a study published in the Feb. 19 New England Journal of Medicine.

In the study, which took place at the Queen Mary University of London, more than 14,200 young women ages 16–26 from North America, South America, Europe and Asia were given either Gardasil or Gardasil 9, said Elmar Joura, lead author of the study and an associate professor at the Medical University of Vienna in Austria.     

The results showed that patients who received the Gardasil 9 vaccine were diagnosed with fewer cases of cervical, vulvar or vaginal disease related to HPV types 31, 33, 45, 52 and 58. The efficacy rate of the new vaccine was 96.7 percent, according to the study.

Joura said Gardasil 9 may have positive repercussions for women at risk of developing cancer from HPV infections, resulting in a reduction in routine cervical cancer screenings. 

“It will definitely have an impact on cervical cancer screening because you will see less and less cancers and also less pre-cancerous lesions,” Joura said. “The age to start screening might change, and also the number of examinations during someone’s lifetime may substantially be decreased.”

According to the Illinois Department of Public Health, 6.38 percent of Chicago women ages nine to 26 have received HPV vaccinations and only 4.35 percent of men of the same age bracket have also received the full course of vaccinations.

Nita Lee, an OB-GYN who specializes in cervical oncology and an assistant professor of Obstetrics and Gynecology at the University of Chicago, said since the creation of Gardasil, HPV in young people is now easily preventable, and the new more effective vaccine will help reduce more instances of HPV-related cancers. 

“The newer vaccine is actually exciting because of the fact that it does have additional viral strands that it protects against, versus just doing 16 and 18, in terms of what the cancer-causing strains were,” Lee said. “Gardasil 9 tries to get a better population estimate about which viral strains are going to be the most effective and target the clinical problem.”

Lee said the majority of women who have an HPV infection will never develop cervical cancer. STD, STI and HPV testing and pap smears are the best methods to detect which cells are pre-cancer or cancer cells and which are merely infectious, she said. 

There are more than 140 types of HPV that are known to infect the genital tract and 13–14 high-risk strains that are known to cause cancer, said Sylvia Ranjeva, a Ph.D. student at the University of Chicago. Two of those high-risk strains, 16 and 18, are known to cause 80 percent of all cervical cancers and are rendered harmless by the existing vaccines. Low-risk strains, such as types 6 and 11, do not cause cancer but result in other types of STI symptoms such as genital warts, she said.

“The high-risk types are not typically associated with the development of warts that people notice right away, and they come up as cervical abnormalities in pap smears later on,” Ranjeva said. “But [types six and 11] are not known to cause cancer, and that’s the major clinical distinction between the high-risk and low-risk types.”

Besides genital warts, Lee said women may experience other noticeable symptoms, including pain, abnormal discharge and fever.However, some symptoms are never present even though the person may have contracted HPV infections, which is why it is important for women to be screened regularly, Lee said.

“HPV is a very prevalent sexually transmitted disease, so anybody who ever had sex once is at risk for developing HPV,” Lee said. “Gardasil 9 is a vaccine that could stop a significant amount of women from developing cervical cancer, anal cancer and head and neck cancers.”