Boys and young men who receive the human papillomavirus (HPV) vaccine appear to be at reduced risk of contracting the virus and developing the genital warts associated with the common sexually transmitted disease, according to a large international study published this week in the New England Journal of Medicine. In an effort to prevent cervical cancer, which can be caused by HPV, public health officials have been encouraging young women to get vaccinated since the Food and Drug Administration approved the first HPV vaccine, Gardasil, in 2006. The vaccine has been approved for boys and men since 2009, but health officials and doctors haven't pushed it with the same urgency.
"Because the story started with cervical cancer, the studies started with females," said the lead author of the study, Anna Giuliano, Ph D, of the H Lee Moffitt Cancer Center and Research Institute in Tampa, Florida. "The study of HPV in men is a late bloomer." Gardasil is given in a series of three injections. In the study, which included more than 4,000 sexually active males between the ages of 16 and 26, roughly 0.5 per cent of the boys and men who received all three shots developed genital warts during the subsequent two to three years. By contrast, about 2.8 per cent of the study participants who received a placebo vaccine developed warts.
The vaccine also reduced the risk of contracting an HPV that persists for at least six months, though not as dramatically. HPV can cause certain cancers of the anus and penis in men, although those diseases are far less common than cervical cancer in women. The study was designed and funded by Merck, the maker of Gardasil (also known as Silgard). The National Institutes of Health also provided funding.
An estimated 20 million Americans are currently infected with HPV. Symptoms are rare, however, so most people have the virus-and pass it on-without realising it.
"Men are such a vital component of the whole prevention cycle when looking at HPV or any sexually transmitted infection," said Demetrius Porche, a professor of nursing research and evaluation at the Louisiana State University School of Public Health in New Orleans. Vaccinating men provides a "double benefit" in that fewer men with HPV will also mean that fewer women are exposed, added Porche, who was not involved in the current study but has researched HPV in men. Earlier this week, for the first time, the American Academy of Paediatrics included the HPV vaccine on its list of recommended vaccines for boys. Porche and Giuliano also urge boys and men to get vaccinated.
HPV Facts
Human papillomaviruses (HPV) are a group of more than 100 viruses. They are called papillomaviruses because certain types may cause warts, or papillomas, which are benign (noncancerous) tumours. The HPVs that cause the common warts that grow on hands and feet are different from those that cause growths in the throat or genital area. Some "high-risk" types of HPV are associated with certain types of cancer, mostly commonly cervical cancer. Of the more than 100 types of HPV, over 30 types can be passed from one person to another through sexual contact. Although HPVs are usually transmitted sexually, doctors cannot say for certain when infection occurred. Most HPV infections occur without any symptoms and go away without any treatment over the course of a few years. However, HPV infection sometimes persists for many years.
How common is HPV?
Approximately 20 million people are currently infected with HPV. At least 50 per cent of sexually active men and women acquire genital HPV infection at some point in their lives. By age 50, at least 80 per cent of women will have acquired genital HPV infection.
How is it diagnosed?
Most women are diagnosed with HPV on the basis of abnormal Pap tests. A pap test is the primary cancer-screening tool for cervical cancer or pre-cancerous changes in the cervix, many of which are related to HPV. No HPV tests are available for men.
Is there a cure?
There is no cure for HPV infection, although in most women the infection goes away on its own. The treatments provided are directed to the changes in the skin or mucous membrane caused by HPV infection, such as warts and pre-cancerous changes in the cervix.
(CNN Health)