clear
Saturday May 28th, 2016 6:07PM

HPV vaccine cut infection by half in teen girls

By The Associated Press
ATLANTA - A vaccine against a cervical cancer virus cut infections in teen girls by half in the first study to measure the shot's impact since it came on the market. The results impressed health experts and a top government top health official called them striking.

The research released Wednesday echoes studies done before the HPV vaccine became available in 2006. But the new study is the first evidence of just how well it works now that it is in general use.

Only about half of teen girls in the U.S. have gotten at least one dose of the expensive vaccine, and just a third of teen girls have had all three shots, according to the latest government figures.

"These are striking results and I think they should be a wake-up call that we need to increase vaccination rates,'' said Dr. Thomas Frieden, director of the Centers for Disease Control and Prevention.

Cervical cancer is caused by certain types of the common sexually transmitted virus called HPV, for human papillomavirus. The vaccine, which costs about $130 per dose, protects against a few of those strains, including two blamed for 70 percent of cervical cancers. The shots work best if given before someone is sexually active so the emphasis has been on giving the shots to 11- and 12-year olds.

The CDC study compared infection rates in girls ages 14 to 19 before and after the vaccine became available. The proportion infected with the targeted HPV strains dropped 56 percent, from about 12 percent before the vaccine was sold to 5 percent. That result was for all teens after it was on the market, whether or not they were vaccinated.

Among girls who had gotten the vaccine, the drop in HPV infections was higher 88 percent.

There are two vaccines against HPV, but the study mainly reflects the impact of Gardasil, the Merck & Co. vaccine that came on the market in 2006. A second vaccine approved in 2009 GlaxoSmithKline's Cervarix probably had relatively little bearing on the results, said the CDC's Dr. Lauri Markowitz, the study's lead author.

Both vaccines are approved for use in males and females in ages 9 to 26 for females, and 9 to 21 in males. The vaccine was only recommended for boys in late 2011, and the CDC has not yet reported data on how many boys have gotten the shot since then. HPV vaccination requires three shots over 6 months.

An estimated 75 to 80 percent of men and women are infected with HPV during their lifetime. Most don't develop symptoms and clear it on their own. But some infections lead to genital warts, cervical cancer and other cancers. The study didn't look at cervical cancer rates. It can take many years for such cancers to develop, and not enough time has passed to know the vaccine's impact on cancer rates, CDC officials said.

The study involved interviews and physical examinations of nearly 1,400 teen girls in 2003 through 2006 and of 740 girls in 2007 through 2010.

The vaccine's impact was seen even though only 34 percent of the teens in the second group had received any vaccine. That could be due to ``herd immunity'' when a population is protected from an infection because a large or important smaller group is immune.

Only about 20 percent of those vaccinated got all three doses. That result will likely feed an ongoing discussion about whether all three doses are necessary, Markowitz said.

Overall, the study found no significant change over time in the proportion of teens who'd ever had sex and in those who had multiple sex partners. However, it did find that a higher percentage of vaccinated teens said they'd had three or more sex partners.

That could have driven down infection rates, Markowitz noted, if the teens who got vaccinated were the ones at highest risk of getting an infection and spreading it.

The research was released online by the Journal of Infectious Diseases.
© Copyright 2016 AccessWDUN.com
All rights reserved. This material may not be published, broadcast, rewritten, or redistributed without permission.
S&P 500 index has its best year since 1997
The stock market closed out a record year with more all-time highs on Tuesday, giving U.S. indexes their biggest annual gains in almost two decades.
6:56PM ( 2 years ago )
Colorado readies for 'Green Wednesday' pot sales
Police were adding extra patrols around pot shops in eight Colorado towns that plan to allow recreational sales to anyone over 21 on Jan. 1.
1:52PM ( 2 years ago )
Kerry seeks framework for Mideast peace talks
A senior State Department official says Secretary of State John Kerry will try this week to get Israel and the Palestinians to agree on a framework for negotiating a final peace agreement, yet cautions against raising expectations for Kerry's latest round of shuttle diplomacy.
1:35PM ( 2 years ago )
U.S. News
Ethics laws set to take effect Jan. 1 in Georgia
After dominating much of the legislative session, a set of major ethics reforms is scheduled to take effect Jan. 1.
7:04PM ( 2 years ago )
Sex offender held in Hall County for failing to register
A 47-year-old man was booked into the Hall County Jail Tuesday, being held without bond for allegedly failing to register as a sex offender, his second such arrest.
6:09PM ( 2 years ago )
Pharmacy robberies may involve same suspect
Oakwood Police Tuesday afternoon released details in a pharmacy robbery they're investigating, similar to one that happened in the Hall County Tuesday morning.
5:46PM ( 2 years ago )
Local/State News
Amid shouts of 'shame,' House GOP defeats gay rights measure
Democrats shouted "shame," but House Republicans switched their votes and defeated a measure to protect gay rights
8:03PM ( 1 week ago )
CDC director Freiden warns GOP Zika bill is inadequate
The head of the Centers for Disease Control and Prevention warned Wednesday that a House GOP measure to combat the Zika virus is inadequate to deal with the swelling threat to public health
7:36PM ( 1 week ago )
Trump unveils list of his top picks for Supreme Court
Donald Trump, the presumptive Republican nominee for president, released Wednesday a list of 11 potential Supreme Court justices he plans to vet to fill the seat of late Justice Antonin Scalia if he's elected to the White House.
3:31PM ( 1 week ago )
1st US penis transplant could bring hope to maimed soldiers
A 64-year-old cancer patient has received the nation's first penis transplant, a groundbreaking operation that may also help U.S. veterans maimed by roadside bombs
8:04PM ( 1 week ago )
States dig in against directive on transgender bathroom use
Politicians in Texas, Arkansas and elsewhere are vowing defiance over the Obama administration's new directive on transgender bathroom use
9:19PM ( 2 weeks ago )