18 July 2014: The Human Papillomavirus (HPV) can put the health of both men and women at risk, says Dr Trudy Smith, Johannesburg-based gynaecologist and obstetrician. Cervical, anal and penile cancers, along with genital warts are but some of the nasty diseases one can contract from the hardy and easily transmittable virus she says.
HPV is a very common virus with more than 130 strains1, 40 strains which affect the genital area2. While most people clear the virus naturally1, others are not able to and it can lead to genital warts; cancers of the cervix, vulva, vagina, anus, penis, and throat2,3.
“HPV is a particularly strong virus that can cause infections which lead to cancer in both men and women,” says Dr Smith. “There are often no symptoms of HPV infection and it can lie undetected for years. In that time, the infected person can pass it unknowingly onto others.”
The virus is easily spread by many forms of genital contact – sexual intercourse doesn’t need to take place4. Research shows that individuals aged 15 to 24 years are at highest risk for genital HPV infection2.
Men also at risk
There is little awareness that boys and men can also be infected with and transmit HPV. In recent studies conducted in men, the prevalence of genital HPV infection appears to be at least as high as that among women2. Genital warts are the best known HPV-related disease in boys and men, however HPV has also been linked to anal, and penile cancers in men1,3.
Cancers in Women
“Although screening programmes for HPV in boys and men are lacking, pap smears may detect certain cancer-causing strains of HPV in women,” says Professor Hennie Botha, Head of Gynaecological Oncology at the University of Stellenbosch.
In women, HPV causes most cases of cervical cancer – the number 1 ranked cancer in women aged 15 to 44 in Southern Africa5, and one of the leading causes of female cancer-related deaths in South Africa5.
Professor Botha says HPV can be a silent killer, because those with the infection often only seek help when a resultant cancer is at an advanced stage.
“Many women are diagnosed with cervical cancer in their mid to late thirties,” he adds. “Many of these women were most likely exposed to cervical cancer-causing HPV types during their teens and twenties.”
Cutting the Risk – Multi-strain Vaccines
“The most exciting development in the prevention of these diseases is the availability of HPV vaccines which help the body’s immune system learn how to protect itself against HPV infection,” says Professor Botha. “These vaccines mean it is now possible to prevent some of the nastiest cancers around.”
There is currently no one HPV vaccine that protects against all of the subtypes. There are currently two HPV vaccines in the market. One vaccine covers two HPV subtypes (subtypes 16 and 18), protecting against cervical cancer and related lesions. The other vaccine covers four HPV subtypes (HPV 6, 11, 16 and 18) which protect against both cervical cancer and related lesions as well as genital warts in both males and females. HPV subtypes 16 and 18 cause 70% of cervical cancers and HPV subtypes 6 and 11 cause 90% of genital warts6, 7 8.
“A multi-strain vaccine is highly effective in preventing HPV-related cervical cancers and genital warts,” says Professor Botha.
Best Time to Vaccinate
Research shows that individuals aged 15 to 24 years are at highest risk for genital HPV infection2.
“The best time to vaccinate both male and female children is between the ages of nine and 13 years, because the younger someone is, the better their body’s ability to mount an immune response against HPV,” explains Professor Botha.
The best protective results for vaccination are also seen in those who have not yet had contact with the virus9.
“Remember that a vaccination is not a treatment for an existing disease, such as cancer or genital warts, but can help prevent these conditions,” says Dr Smith.
Professor Botha hopes that if enough people in the population are vaccinated against the most dangerous strains of HPV, these may eventually be eradicated altogether. “If enough boys and girls are vaccinated, we could wipe out the worst cancer-causing HPV viruses in future,” says Professor Botha.
For more information on HPV-related diseases, please visit www.hpv.co.za. Your healthcare professional will be able to discuss the optimum vaccination schedule with you in more detail.
1 Hathaway JK. HPV: Diagnosis, prevention and treatment. Clinical Obstetrics and Gynaecology. 2012; 55(3):671-680.
2 Weaver BA. Epidemiology and natural history of genital human papillomavirus infection. JAOA. 2006; 6(3):S1-S8.
3 Jin XW, Lipold L, Sikon A, Rome E. Human papillomavirus vaccine: safe, effective, underused. Cleveland Clin J Med 2013; 80(1):49-60.
4 Winer RL, Lee S-K, Hughes JP, et al. Genital human papillomavirus infection: Incidence and risk factors in a cohort of female university students. Am J Epidemiol 2003; 157: 218–226.
5 ICO information centre on HPV and cancer. South Africa human papillomavirus and related cancers, fact sheet 2013 (January 31, 2014). Accessed on: 30th of June 2014. Available on http://www.hpvcentre.net/statistics/reports/ZAF_FS.pdf .
6 Arima Y, Winer RL, Feng Q, et al. Development of genital warts after incident detection of human papillomavirus infection in young men. The Journal of Infectious Diseases 2010; 202(8):1181–1184.
7 Cervarix approved package insert. MIMS Desk Reference. 2013. Volume 48. Pg. 471- 479.
8 Gardasil approved package insert. 10 April 2014. MSD South Africa.
9 The FUTURE II Study Group. Quadrivalent vaccine against human papillomavirus to prevent high-grade cervical lesions. New England Journal of Medicine 2007; 356(19): 1915-1927.