Study: Current HPV vaccine may not help immune-compromised women
There are more than 40 types of HPV that can infect the genital areas, at least 15 of which are considered high-risk for cancer. But some strains of the virus that are not high-risk may still lead to cancer in a compromised immune system.
"But if your immune system is compromised, such as in HIV, you will not be able to fight off the infection," Elizabeth Blackman, a research specialist at Fox Chase and the lead author of the study, said. "Over time, persistent infection with HPV can lead to cancer."
Blackman and her colleagues presented the research on Sunday at the American Association for Cancer Research Annual Meeting 2013. The researchers found the current HPV vaccines Gardasil and Cervarix may not protect women with HIV and other immune-compromising diseases.
"People with issues in their immune system such as HIV will be at risk of acquiring HPV, as well - and the current vaccine may not fully protect them," Blackman said.
The researchers tested 176 HIV-positive women living in the Bahamas for the presence of high-risk HPV forms. Approximately 75 percent of the women tested carried high-risk forms of HPV and approximately 30 percent had precancerous cervical cells. The women with precancerous cells carried HPV types 16 and 18, which are covered by current HPV vaccines, but also types 52 and 58, which are high-risk but not covered by Gardasil and Cervarix.
The Fox Chase researchers also found that women taking HIV medications for at least four years were less likely to carry cancer-causing forms of HPV. The results suggested that controlling the immune system could reduce additional infections.
"If women take medications for a long enough time, their immune system may prevent other diseases from developing," Blackman said.