ATLANTA (AP) — A vaccine against cervical cancer hasn't been all that popular for girls. It may be even a harder sell for boys now that it's been recommended for them too.
A government advisory panel on Tuesday decided that the vaccine should also be given to boys, in part to help prevent the cancer-causing virus through sex.
Public health officials have tried since 2006 to get parents to have their daughters vaccinated against the human papillomavirus, or HPV, which causes most of the cervical cancer in women.
They have had limited success, hitting a number of hurdles. Some parents distrust the safety of vaccines, especially newer products. Others don't want to think about their daughters having sex one day, or worry that the vaccine essentially promotes promiscuous behavior.
Tuesday's vote by the Advisory Committee on Immunization Practices' was the first to strongly recommend routine vaccination for boys since the vaccine was first approved for them two years ago. Officials acknowledged the low rate in girls encouraged them to take a new, hard look.
Experts say a key benefit of routinely vaccinating boys could be preventing the spread of the virus to others through sex — making up somewhat for the disappointing vaccination rate in girls. But the recommendation is being framed as an important new measure against cancer in males.
"Today is another milestone in the nation's battle against cancer," said Dr. Anne Schuchat, a U.S. Centers for Disease Control and Prevention administrator who oversees the agency's immunization programs.
Federal health officials usually adopt the panel's recommendations and ask doctors and patients to follow them.
The vaccine has been advised for girls since 2006. Just 49 percent of adolescent girls have gotten at least the first of the three HPV shots. Only a third had gotten all three doses by last year.
"Pretty terrible," Schuchat said.
Schuchat attributed the low rates for girls to confusion or misunderstanding by parents that they can wait until their daughter becomes sexually active. It works best if the shots are given before a girl or boy begins having sex.
Some conservatives argue the vaccine could promote promiscuous behavior. It has come up in the GOP presidential campaign. Texas Gov. Rick Perry came under attack for a 2007 executive order requiring adolescent girls to get the vaccine (with an opt-out clause). When conservative lawmakers rebelled, he backed down.
An estimated 75 to 80 percent of men and women are infected with HPV during their life, but most don't develop symptoms or get sick, according to the CDC. Some infections lead to genital warts, cervical cancer and other cancers, including of the head and neck.
The HPV vaccine is approved for use in males and females ages 9 to 26; it is usually given to 11- and 12-year olds when they get other vaccines. The committee also recommended that males 13 to 21 years get vaccinated.
Tuesday's vote follows recent studies that show the vaccine prevents anal cancer in males, and may work against a type of throat cancer. A study that focused on gay men found it to be 75 percent effective against anal cancer.
While anal cancer has been increasing, it's still fairly rare. Only about 7,000 U.S. cases in men each year are tied to the strains targeted in the HPV vaccine. In contrast, about 15,000 vaccine-preventable cervical cancers in women occur annually.
Preventing a cancer that's primarily associated with gay men may not be much of a selling point, said Dr. Ranit Mishori, a family practice doctor in Washington, D.C. and an assistant professor at the Georgetown University School of Medicine.
Some parents may say "'Why are you vaccinating my son against anal cancer? He's not gay! He's not ever going to be gay!' I can see that will come up," said Mishori, who supports the panel's recommendation.
Schuchat indicated the CDC is ready for that kind of argument: "There's no data suggesting that offering a vaccine against HPV will change people's subsequent sexual behavior," she said.
So far, the threat of genital warts hasn't been persuasive: Some data suggest that less than 1.5 percent of adolescent males have gotten the vaccine over the past two years.
Meanwhile, some feel it's unlikely that most parents will agree to get their sons vaccinated primarily to protect girls. A survey of 600 pediatricians last year found that nearly 70 percent of doctors thought families would deem vaccination of their boys as unnecessary.
Experts at the committee meeting noted an earlier analysis that showed vaccinating boys would not be cost-effective if the female vaccination were high.
"If you do reach high coverage of females, will you stop vaccinating males?" asked Dr. David Salisbury, director immunization for the United Kingdom's Department of Health.
There are two vaccines against HPV, but Tuesday's vote applies only to Merck & Co.'s Gardasil, which costs $130 a dose. The other vaccine wasn't tested for males.
The committee's recommendation — and the greater insurance coverage of the vaccine that is expected to follow — will make it easier for more boys to get the shots, said Dr. Mark Feinberg, chief public health and science officer for Merck Vaccines.
Merck officials bristled at the idea that males would see the vaccine as mainly meant for gay men, noting that HPV-caused anal cancers can occur in heterosexual men.
Maura Robbins of Chicago said she's likely to have her 12-year-old son, Cole, vaccinated against HPV — but probably not until he's a little older. "I would just like to see some long-term testing and long-term results," she said.
<한글기사>
"자궁경부암 백신, 男兒도 맞아야"
미국질병통제예방센터(CDC) 예방접종자문위원회 (ACIP: Advisory Committee on Immunization Practices)는 자궁경부암 예방 백신을 남자아이들에게도 맞힐 것을 CDC에 권고했다고 AP통신 등이 25일 보도했다.
ACIP는 자궁경부암을 일으키는 인유두종바이러스(HPV)가 남성에게도 나타나는 성병의 일종인 콘딜로마(성기 사마귀)와 직장암을 일으킬 수 있는 만큼 이를 예방하 고, 여성의 HPV 감염을 간접적으로 차단하기 위해 11-12세의 남자아이들에게도 자궁 경부암 백신을 접종할 필요가 있다고 밝혔다.
CDC는 ACIP의 권고를 받아들일 것인지를 두 달 안에 결정하게 된다.
ACIP의 이 같은 권고는 여자아이들의 HPV 백신 접종이 부진하자 이를 간접적으 로 보완하기 위해 나온 것으로 보인다.
CDC 면역-호흡기질환센터의 앤 슈차트 실장은 5년에 걸쳐 3번 맞아야 하는 HPV 백신을 1회 접종한 사춘기 소녀들은 49%에 불과하며, 이들 중 작년까지 2-3회 추가 접종을 완료한 경우는 3분의 1에 불과하다고 밝히고 HPV 백신의 여성 접종률이 이처 럼 낮을 땐 남성을 접종시키는 것이 가장 효과적인 방법이라고 지적했다.
슈차트 실장은 소녀들의 접종률이 이처럼 낮은 것은 성관계를 시작되기 전에는 맞힐 필요가 없다는 부모의 잘못된 생각 때문이라면서 이 백신은 성행위를 시작하기 전에 접종했을 때 최고의 효과를 기대할 수 있다고 말했다.
HPV 백신은 머크 제약회사의 가다실과 글락소스미스클라인 제약회사의 서바릭스 가 있지만 남성용으로도 승인을 받은 것은 가다실뿐이다.
40여 종류의 HPV 가운데 자궁경부암을 일으키는 4종류(6-11-16-18형)를 표적으 로 하는 가다실은 2006년 9-26세의 여성용으로 승인됐고 이어 2009년 같은 연령대의 남성용으로도 추가 승인을 받았다.
서바릭스는 두 종류의 HPV(16-18형)를 대상으로 한 자궁경부암 백신으로 2009년 10-25세 여성용으로 승인을 받았다.
HPV는 성행위에 의해 감염되는 가장 흔한 바이러스로 성생활이 활발한 연령대의 남녀 중 절반은 평생에 한 번은 감염되는 것으로 알려져 있다.
HPV는 여서의 자궁경부암 외에도 남성 동성애자들에게는 직장암, 구강성교 행위 자에게는 두경부암을 유발할 수 있다.
