Some men do not even know they are killers.

There are many misconceptions that say the human papillomavirus (HPV) only affects women, but men are certainly not in the clear.

About one in four people in the United States are currently infected with some form of HPV, which is the most common sexually transmitted disease today.

Forty-five percent of men and women are infected with HPV in the U.S., according to Dr. Janice Han, a doctor in the division of gynecologic oncology at Womack Army Medical Center, in Fort Bragg, N.C.

HPV vaccination rates are higher in women than they are in men. In 2006, women were recommended by the Advisory Committee on Immunization Practices (ACIP) to get the Gardasil shot to prevent HPV-related cancers. Men, however, were not introduced to the vaccine until 2011, according to Dr. Elissa Meites, a medical epidemiologist with the division for viral diseases at the Centers for Disease Control and Prevention (CDC).

“Most sexually active people will have at least one type of HPV at some point in their life, although most of those infections will go away,” Meites said.

HPV comes in more than 150 different forms. The infection can cause cancer in both men and women. Most HPV infections go away on their own. But if they persist longer than a year or two, they can develop into genital warts or cancer, according to Meites.

In 2015, 50 percent of boys who had at least one dose of the vaccine were covered from developing HPV. Although, for girls of the same age and dose amount, the coverage rate is almost 13 percent higher, she said.

“Coverage in boys is still lagging behind in coverage in girls, but the update for them has been quicker considering the recommendation did not come out for boys for a few extra years,” according to Meites.

Two doses are now recommended for children to start their vaccination series before their 15th birthday and three doses remain recommended for people who initiated the vaccine series on or after their 15th birthday. The change in the recommended doses was based on new data that showed two doses work just as well as three, according to Meites.

Each shot costs about $140. Although, most insurance plans will cover the cost of the vaccine series. Vaccines are also included in the federal Vaccines for Children (VFC) program. The program fully covers vaccine costs for children younger than 19 years old who do not have insurance or those who are underinsured, according to the American Cancer Society website.

HPV vaccination rates have risen in Arizona because of increased community awareness about the virus.

Nurses at the University of Arizona campus health have seen a noticeable decrease in HPV rates among women in their early 20s since Gardasil was introduced in 2006, according to Lee Ann Hamilton, assistant director of health promotion and preventive services at UA Campus Health.

Hamilton believes HPV rates have dropped in college women because Gardasil has become more popular over the last decade and because men, who are the carriers of HPV, have also been encouraged to get the vaccine in recent years.

“If there are enough people who aren’t spreading it, then that helps everybody else who hasn’t been vaccinated,” Hamilton said.

Jennifer Tinney, program director of The Arizona Partnership for Immunization (TAPI), believes the most important reason young children should get the HPV vaccination is to protect their futures before they become sexually active or get exposed to the virus later in life.

TAPI meets regularly with health departments, private physicians, community members and agencies in the state to find out what needs to be addressed with immunizations.

Long-term health effects of HPV are as detrimental to men as they are for women. The widespread of the disease becomes greater when just one person does not get vaccinated, according to Hamilton.

Andrew Le, a student at the University of Arizona who studies biochemistry, said he believes that the Gardasil shot has positive effects in preventing the spread of HPV, but he was unaware that men could get the vaccine.

“I would assume it shouldn’t be any different for men to get the vaccine as it is for women,” Le said.

According to Tinney, TAPI has developed a long-range strategy to increase HPV immunization rates in Arizona through community awareness.

Talking about HPV is the most effective way to get parents to vaccinate their children, according to Tinney. There are always questions behind the effectiveness of the HPV vaccine, but Centers for Disease Control research has shown that parents are curious about it and want more information so they can protect their children.

“The vaccine is not necessarily preventing a case of the flu that could happen in the next month or so,” Tinney said. “HPV is long-range, and it is important that we get children vaccinated young while their immune systems are healthy and well.”

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