Over a quarter million women die each year in Uganda from cervical cancer. The primary cause is the human papillomavirus, or HPV. In 2010, vaccines were developed and introduction to the community has commenced. Recent randomised trials have also shown that when men are circumcised it provides protection against transmission of HPV to women.
Approximately 55% to 65% of all newborn boys are circumcised in the United States each year, though this rate varies by region (western states have the lowest rates and the north central region has the highest). The procedure is much more widespread in the United States, Canada, and the Middle East than in Africa, Asia, South America, Central America, and most of Europe, where it's uncommon.
Dr. Anna R. Giuliano, Department of Cancer Epidemiology and Genetics, H. Lee Moffitt Cancer Center explains:
"Recent findings add important evidence for the promotion of male circumcision in countries without well-established programmes for cervical screening. Additional interventions to reduce HPV infection, such as provision of vaccines for HPV prevention, will be essential to reduce invasive cervical cancer worldwide. Male circumcision is associated with slight reductions in high-risk HPV, while licensed HPV vaccines protect with high effectiveness against only a limited number of HPV types. Therefore, the two interventions are likely to have important synergistic effects."
Developed for the Rakai Health Sciences Program in Uganda, and reported by Drs. Aaron Tobian and Maria Wawer, Johns Hopkins University, randomised trials showed that male circumcision reduces the prevalence and incidence of high-risk HPV infection in men. In this study, the authors assessed the effectiveness of male circumcision to prevent high-risk HPV infection in HIV-negative female partners of HIV-negative men who were enrolled in two randomised controlled trials of male circumcision in Uganda.
These controlled trials of male circumcision measured incidence, prevalence, and clearance of high-risk HPV infection in female partners of men randomly assigned to male circumcision immediately or after a delay.
With a computer-generated random number sequence in blocks of 20, men were assigned to undergo circumcision immediately (intervention) or after 24 months (control). Female partners, 648 of men from the intervention group, and 597 of men in the control group, were simultaneously enrolled and provided interview information and self-collected vaginal swabs at baseline, 12 months, and 24 months. Vaginal swabs were then tested for high-risk HPV.
At 24-month follow-up, 28% of women in the intervention group and 39% in the control group had high-risk HPV infection. This means those not circumcised had a 28% higher risk of being infected with HPV.
The study's authors conclude:
"Circumcision of adolescent and adult men in a rural Ugandan population significantly reduced the prevalence and incidence of both low-risk and high-risk HPV infections and increased clearance of high-risk HPV infections in their female partners. Along with previous trial results in men, these findings indicate that male circumcision should now be accepted as an efficacious intervention for reducing heterosexually acquired high-risk and low-risk HPV infections in men who do not have HIV and in their female partners. However, our results indicate that protection is only partial; the promotion of safe sex practices is also important."
Dr Aaron Tobian, Johns Hopkins University, Baltimore, MD, USA.
Dr Anna R Giuliano, Department of Cancer Epidemiology and Genetics, H Lee Moffitt Cancer Center, Tampa, FL, USA.
Written by Sy Kraft, B.A.