Tuesday, November 5th, 2013
A single dose of the vaccine against human papillomavirus, a leading cause of cervical cancer, may be enough to immunize a woman against the disease, a new study has found. Three doses are the current guideline, though research shows that fewer than half of American girls receive the recommended number of doses. More from CNN.com:
“Cervical cancer is a major cause of public health concern, especially in less developed countries where about 85% of cervical cancer occurs,” says study author Mahboobeh Safaeian. “The reason for that is mainly because of lack of screening infrastructure offered.”
Safaeian and her team followed a group of women in Costa Rica who were participating in the National Cancer Institute-funded phase III clinical trial testing the efficacy of Cervarix. About 20% of these women did not complete the three-dose vaccine regimen. Safaeian compared the groups of women who had received one, two and three doses of the vaccine, as well as women who had antibodies from having been naturally infected.
The researchers found that women vaccinated with a single dose of Cervarix, as opposed to the current CDC recommendation of three, had antibodies against HPV that remained stable in their blood after four years. The findings suggest that the common recommendation for three doses may not be necessary to ensure long-lasting antibodies that prevent HPV. Safaeian, a researcher for the National Cancer Institute’s Division of Cancer Epidemiology & Genetics, Infections and Immunoepidemiology, says this could have significant implications for women across the world by simplifying the logistics and costs of vaccinations.
“This vaccine is about $130 a dose … It’s just not feasible in a lot of undeveloped countries,” Safaeian explains.
Image: Girl getting a vaccine, via Shutterstock
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Monday, September 2nd, 2013
A new government report reveals that a surprising number of boys received the vaccine for human papillomavirus (HPV) last year, the first year that it was recommended for adolescent boys. The Centers for Disease Control and Prevention says 1 in 5 boys received at least one dose of the HPV vaccine, NBC News reports.
Shared through sexual contact, HPV can cause cervical cancer in women and genital warts in both sexes, and in rare cases, throat and anal cancer. The vaccine was first recommended for girls ages 11 and 12 beginning in 2006, and then recommended for boys in 2011. More from NBC News:
The shots are largely intended not to protect boys from disease, but to stop them from spreading a sexually transmitted virus to girls that could cause cervical cancer.
The vaccine hasn’t been very popular among girls. The government report issued Thursday is the first real sense of how many boys are getting the shots.
“It’s a good start,” said Shannon Stokley, a vaccination expert with the Centers for Disease Control and Prevention.
Introduced in 2006, the vaccine protects against human papillomavirus, which is spread during sex. Most infections go away on their own, without people developing symptoms. But the virus can cause cervical cancer in females, genital warts in both sexes, and some other, less common conditions like throat and anal cancer.
The vaccine was first recommended for girls ages 11 and 12 because it works best if given before a teen starts to have sex. In 2011, it was also recommended for boys that age to help prevent the virus’s spread.
The CDC report covers vaccination rates for last year, the first full year since the shots were advised for boys. It’s based on telephone calls to families for about 19,000 boys and girls ages 13 to 17.
About 21 percent of the boys had gotten at least one of the three doses. Less than 7 percent were fully vaccinated.
The rates look relatively good compared to the initial rates for some other vaccines aimed at adolescents. For example, the initial rate for a meningococcal vaccine was just 12 percent.
Rates tend to start low when a vaccine is first recommended and build after. So the HPV numbers for boys are reason to be optimistic, said the CDC’s Dr. Melinda Wharton, although she added a word of caution.
“Given how the coverage level has stalled for girls, though, a solid start isn’t enough,” she said.
Image: Three teen boys, via Shutterstock
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Thursday, June 20th, 2013
The rate of infection with the human papillomavirus (HPV) has decreased significantly among teenagers since a vaccine against the virus was introduced in 2006. CNN reports on how the decrease in infection rates has surpassed researchers’ expectations and hopes:
“The prevalence of the types of HPV that commonly cause cervical cancer in women has dropped by about half in girls ages 14 to 19,” said Dr. Thomas Frieden, CDC director. “That decline is even better than we had hoped for.”
Specifically, rates of HPV types 6, 11, 16 and 18 – the four types covered by the vaccines – have decreased by 56% in young girls.
Those numbers are surprising, said Frieden, because only about a third of girls have gotten all three recommended doses of the vaccine. He suggested that the extra immunity may come from girls who only got one or two doses, or so-called “herd immunity.” That occurs when those who have been vaccinated cause there to be less virus floating around, therefore lowering the risk for those who haven’t been vaccinated.
But despite the good news, Frieden says the CDC had hoped that 80% of girls would be vaccinated by this point, and more needs to be done.
“This should be a wake-up call that we need to increase vaccination rates, because we can protect the next generation of girls from cancer caused by HPV,” said Frieden. “Fifty thousand women alive today will develop cervical cancer that could have been prevented if we had reached our goal of an 80% vaccination rate.”
In March, an article in the journal Pediatrics called on more parents to vaccinate their children, expressing concern that the overwhelming majority of girls had not received the full course of the HPV vaccine. Another study, published late last year, found that receiving the HPV vaccine does not affect teens’ sexual behaviors, a concern for many parents.
Image: Teen getting a shot, via Shutterstock
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Thursday, March 28th, 2013
The vaccine against human papillomavirus (HPV), which can cause cervical cancer among other ailments, is in the news again after a survey published in the journal Pediatrics announced that the overwhelming majority of girls have not received the vaccine despite the urging of major medical groups. The New York Times has more:
Just 35 percent of girls 13 to 17 have received a full course of the vaccine, which inoculates against the strains of human papillomavirus that can cause cervical cancer, according to 2011 data from the Centers for Disease Control and Prevention. And a study in Pediatrics this month, also based on C.D.C. data, says the intent to vaccinate is declining: 44 percent of parents in 2010 said they did not intend to vaccinate, up from 40 percent in 2008.
Alarmed by the stubbornly low rates, doctors and federal health officials are brainstorming about how to get more children vaccinated.
“Behind these numbers are people who will develop cervical cancer that could have been prevented,” said Dr. Bruce Gellin, director of the National Vaccine Program Office at the Department of Health and Human Services. At a meeting in Washington last month, federal and local officials, doctors and other health workers explored ways to make the shots more accessible. Some suggested giving the first of the three doses required to complete the vaccine at a doctor’s office and the other two at schools or pharmacies.
Others argued for a greater emphasis on cancer prevention, playing down the fact that the vaccine prevents a sexually transmitted disease. The STD link has put off many parents who are loath to talk about sex with their children.
Image: Girl getting a shot, via Shutterstock
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Tuesday, March 19th, 2013
A survey of parents has found that many teenagers are not receiving vaccine boosters that are readily available, proven safe, and important protectors against serious but preventable diseases. CNN.com reports:
“These vaccines are safe and effective and people should really have their teens get them,” says Dr. Paul Darden, lead author of the study and professor of pediatrics at the University of Oklahoma College of Medicine. “Parents say pediatricians are telling them about the vaccines, yet they just don’t seem to understand why they are necessary or are skeptical about their safety.”
When parents of teens were asked why their children didn’t receive certain forms of the tetanus, diphtheria, pertussis (Tdap) and meningitis vaccine, some parents noted these shots were not recommended or not necessary, according to the study. Others did not have a reason.
Regarding the controversial and fairly new vaccine that protects against the sexually transmitted human papillomavirus – which has been linked to cancer – some parents also said it was not necessary. In other cases parents noted their children were not sexually active or were not the appropriate age to receive the vaccine.
Concerns of mothers and fathers about the safety of the HPV vaccine grew each year, from 4.5% in 2008 to 16.4% in 2010, according to the study. The number of parents who said they would not vaccinate their children for HPV increased from 39.8% in 2008 to 43.9% in 2010. The main concern was safety.
Investigators were surprised, because the vaccine has been found to be very effective in preventing the virus that causes cervical cancer in young women.
“We thought perhaps many parents would think the HPV vaccine would give kids permission to have sex, and therefore not allow their children to get it. But that wasn’t it,” explained Darden. “They seemed to be skeptical of its safety, which is odd, because it’s shown to be effective with few side effects. We have a vaccine that protects against cancer. Why not vaccinate your child? I don’t get it.”
Image: Teen girl getting a shot, via Shutterstock
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