vaccination

The Unforgiving Math That Stops Epidemics

Author: Tara C. Smith
Source: www.quantamagazine.org
Date: October 26, 2017

As the annual flu season approaches, medical professionals are again encouraging people to get flu shots. Perhaps you are among those who rationalize skipping the shot on the grounds that “I never get the flu” or “if I get sick, I get sick” or “I’m healthy, so I’ll get over it.” What you might not realize is that these vaccination campaigns for flu and other diseases are about much more than your health. They’re about achieving a collective resistance to disease that goes beyond individual well-being — and that is governed by mathematical principles unforgiving of unwise individual choices.

When talking about vaccination and disease control, health authorities often invoke “herd immunity.” This term refers to the level of immunity in a population that’s needed to prevent an outbreak from happening. Low levels of herd immunity are often associated with epidemics, such as the measles outbreak in 2014-2015 that was traced to exposures at Disneyland in California. A study investigating cases from that outbreak demonstrated that measles vaccination rates in the exposed population may have been as low as 50 percent. This number was far below the threshold needed for herd immunity to measles, and it put the population at risk of disease.

The necessary level of immunity in the population isn’t the same for every disease. For measles, a very high level of immunity needs to be maintained to prevent its transmission because the measles virus is possibly the most contagious known organism. If people infected with measles enter a population with no existing immunity to it, they will on average each infect 12 to 18 others. Each of those infections will in turn cause 12 to 18 more, and so on until the number of individuals who are susceptible to the virus but haven’t caught it yet is down to almost zero. The number of people infected by each contagious individual is known as the “basic reproduction number” of a particular microbe (abbreviated R0), and it varies widely among germs. The calculated R0 of the West African Ebola outbreak was found to be around 2 in a 2014 publication, similar to the R0 computed for the 1918 influenza pandemic based on historical data.

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If the Ebola virus’s R0 sounds surprisingly low to you, that’s probably because you have been misled by the often hysterical reporting about the disease. The reality is that the virus is highly infectious only in the late stages of the disease, when people are extremely ill with it. The ones most likely to be infected by an Ebola patient are caregivers, doctors, nurses and burial workers — because they are the ones most likely to be present when the patients are “hottest” and most likely to transmit the disease. The scenario of an infectious Ebola patient boarding an aircraft and passing on the disease to other passengers is extremely unlikely because an infectious patient would be too sick to fly. In fact, we know of cases of travelers who were incubating Ebola virus while flying, and they produced no secondary cases during those flights.

Note that the R0 isn’t related to how severe an infection is, but to how efficiently it spreads. Ebola killed about 40 percent of those infected in West Africa, while the 1918 influenza epidemic had a case-fatality rate of about 2.5 percent. In contrast, polio and smallpox historically spread to about 5 to 7 people each, which puts them in the same range as the modern-day HIV virus and pertussis (the bacterium that causes whooping cough).

Determining the R0 of a particular microbe is a matter of more than academic interest. If you know how many secondary cases to expect from each infected person, you can figure out the level of herd immunity needed in the population to keep the microbe from spreading. This is calculated by taking the reciprocal of R0 and subtracting it from 1. For measles, with an R0 of 12 to 18, you need somewhere between 92 percent (1 – 1/12) and 95 percent (1 – 1/18) of the population to have effective immunity to keep the virus from spreading. For flu, it’s much lower — only around 50 percent. And yet we rarely attain even that level of immunity with vaccination.

Once we understand the concept of R0, so much about patterns of infectious disease makes sense. It explains, for example, why there are childhood diseases — infections that people usually encounter when young, and against which they often acquire lifelong immunity after the infections resolve. These infections include measles, mumps, rubella and (prior to its eradication) smallpox — all of which periodically swept through urban populations in the centuries prior to vaccination, usually affecting children.

Do these viruses have some unusual affinity for children? Before vaccination, did they just go away after each outbreak and only return to cities at approximately five- to 10-year intervals? Not usually. After a large outbreak, viruses linger in the population, but the level of herd immunity is high because most susceptible individuals have been infected and (if they survived) developed immunity. Consequently, the viruses spread slowly: In practice, their R0 is just slightly above 1. This is known as the “effective reproduction number” — the rate at which the microbe is actually transmitted in a population that includes both susceptible and non-susceptible individuals (in other words, a population where some immunity already exists). Meanwhile, new susceptible children are born into the population. Within a few years, the population of young children who have never been exposed to the disease dilutes the herd immunity in the population to a level below what’s needed to keep outbreaks from occurring. The virus can then spread more rapidly, resulting in another epidemic.

An understanding of the basic reproduction number also explains why diseases spread so rapidly in new populations: Because those hosts lack any immunity to the infection, the microbe can achieve its maximum R0. This is why diseases from invading Europeans spread so rapidly and widely among indigenous populations in the Americas and Hawaii during their first encounters. Having never been exposed to these microbes before, the non-European populations had no immunity to slow their spread.

If we further understand what constellation of factors contributes to an infection’s R0, we can begin to develop interventions to interrupt the transmission. One aspect of the R0 is the average number and frequency of contacts that an infected individual has with others susceptible to the infection. Outbreaks happen more frequently in large urban areas because individuals living in crowded cities have more opportunities to spread the infection: They are simply in contact with more people and have a higher likelihood of encountering someone who lacks immunity. To break this chain of transmission during an epidemic, health authorities can use interventions such as isolation (keeping infected individuals away from others) or even quarantine (keeping individuals who have been exposed to infectious individuals — but are not yet sick themselves — away from others).

Other factors that can affect the R0 involve both the host and the microbe. When an infected person has contact with someone who is susceptible, what is the likelihood that the microbe will be transmitted? Frequently, hosts can reduce the probability of transmission through their behaviors: by covering coughs or sneezes for diseases transmitted through the air, by washing their contaminated hands frequently, and by using condoms to contain the spread of sexually transmitted diseases.

These behavioral changes are important, but we know they’re far from perfect and not particularly efficient in the overall scheme of things. Take hand-washing, for example. We’ve known of its importance in preventing the spread of disease for 150 years. Yet studies have shown that hand-washing compliance even by health care professionals is astoundingly low — less than half of doctors and nurses wash their hands when they’re supposed to while caring for patients. It’s exceedingly difficult to get people to change their behavior, which is why public health campaigns built around convincing people to behave differently can sometimes be less effective than vaccination campaigns.

How long a person can actively spread the infection is another factor in the R0. Most infections can be transmitted for only a few days or weeks. Adults with influenza can spread the virus for about a week, for example. Some microbes can linger in the body and be transmitted for months or years. HIV is most infectious in the early stages when concentrations of the virus in the blood are very high, but even after those levels subside, the virus can be transmitted to new partners for many years. Interventions such as drug treatments can decrease the transmissibility of some of these organisms.

The microbes’ properties are also important. While hosts can purposely protect themselves, microbes don’t choose their traits. But over time, evolution can shape them in a manner that increases their chances of transmission, such as by enabling measles to linger longer in the air and allowing smallpox to survive longer in the environment.

By bringing together all these variables (size and dynamics of the host population, levels of immunity in the population, presence of interventions, microbial properties, and more), we can map and predict the spread of infections in a population using mathematical models. Sometimes these models can overestimate the spread of infection, as was the case with the models for the Ebola outbreak in 2014. One model predicted up to 1.4 million cases of Ebola by January 2015; in reality, the outbreak ended in 2016 with only 28,616 cases. On the other hand, models used to predict the transmission of cholera during an outbreak in Yemen have been more accurate.

The difference between the two? By the time the Ebola model was published, interventions to help control the outbreak were already under way. Campaigns had begun to raise awareness of how the virus was transmitted, and international aid had arrived, bringing in money, personnel and supplies to contain the epidemic. These interventions decreased the Ebola virus R0 primarily by isolating the infected and instituting safe burial practices, which reduced the number of susceptible contacts each case had. Shipments of gowns, gloves and soap that health care workers could use to protect themselves while treating patients reduced the chance that the virus would be transmitted. Eventually, those changes meant that the effective R0 fell below 1 — and the epidemic ended. (Unfortunately, comparable levels of aid and interventions to stop cholera in Yemen have not been forthcoming.)

Catch-up vaccinations and the use of isolation and quarantine also likely helped to end the Disneyland measles epidemic, as well as a slightly earlier measles epidemic in Ohio. Knowing the factors that contribute to these outbreaks can aid us in stopping epidemics in their early stages. But to prevent them from happening in the first place, a population with a high level of immunity is, mathematically, our best bet for keeping disease at bay.

November, 2017|Oral Cancer News|

7 million American men carry cancer-causing HPV virus

Source: www.nytimes.com
Author: Nicholas Bakalar

The incidence of mouth and throat cancers caused by the human papilloma virus in men has now surpassed the incidence of HPV-related cervical cancers in women, researchers report.

The study, in the Annals of Internal Medicine, found that 11 million men and 3.2 million women in the United States had oral HPV infections. Among them, 7 million men and 1.4 million women had strains that can cause cancers of the throat, tongue and other areas of the head and neck.

The risk of infection was higher for smokers, for people who have had multiple sex partners, and for men who have sex with men. Frequent oral sex also increased the risk. The rate was higher among men who also had genital HPV. (Almost half of men aged 18 to 60 have a genital HPV infection, according to the Centers for Disease Control and Prevention.)

Neither age nor income made a difference in high-risk oral infection rates, but rates among non-Hispanic blacks were higher than other races and ethnicities.

HPV vaccination is recommended starting at age 11 or 12 and is effective, said the senior author, Ashish A. Deshmukh, an assistant professor at the University of Florida, and “it’s crucial that parents vaccinate boys as well as girls.”

The lead author, Kalyani Sonawane, also at the University of Florida, said that behavioral change is important, too, particularly smoking cessation. “The difference in oral HPV infection between smokers and nonsmokers is staggering,” she said.

October, 2017|Oral Cancer News|

Should women older than 18 get the HPV vaccine?

Source: www.washingtonpost.com
Author: Erin Blakemore

About half of American teenagers have been vaccinated against the human papillomavirus (HPV), the most common sexually transmitted infection in the United States. Should adult women follow suit?

Yes, says Lauri Markowitz, a Centers for Disease Control and Prevention medical epidemiologist who has worked with the advisory committee that makes national vaccination recommendations. “Women 18 to 26 should be vaccinated.”

There’s good reason to follow that recommendation. According to the American Cancer Society, about 12,820 new cases of cervical cancer will be diagnosed in U.S. women this year and more than 4,000 will die of the disease. HPV is thought to be responsible for more than 90 percent of all cervical and anal cancers in men and women. The virus also causes vaginal, vulvar and throat cancers and genital warts.

Although the majority of HPV infections do not cause cancer — most people with an infection never show any symptoms, and infections usually go away on their own — some strains are particularly dangerous. Gardasil 9, the newest HPV vaccine approved by the Food and Drug Administration, protects against nine such strains and, researchers say, may be able to prevent up to 90 percent of cervical cancers. (Older vaccines protect against fewer strains of HPV.)

However, confusion about the way HPV vaccines protect against infection can deter some women. Gardasil 9 is approved for women up to age 26. Like other vaccines, it spurs the body’s immune system to defend itself against a virus. The FDA and CDC say the HPV vaccines are safe and extremely effective: HPV rates in women ages 14 to 19 years fell 64 percent within six years of the vaccine’s introduction in the United States in the mid-2000s and 34 percent in women ages 20 to 24.

The vaccines are most effective if administered before a woman becomes sexually active. The longer a woman has been sexually active and the more partners she has had, the more opportunities she has had to become infected with an HPV strain that overlaps with the vaccine. If she is vaccinated at an older age, the vaccine may be less effective in lowering her cancer risk, Markowitz says. The vaccine can’t clear any HPV that has taken hold; it can only prevent future infection. So essentially if you already have been exposed to one of the strains it protects against, it will be useless against that strain.

That doesn’t mean it’s useless to get vaccinated if you’re older than the recommended age of 11 or 12, Markowitz says. “Your chances of being protected are decreasing, but you will still have some protection,” she says. Although the likelihood that a sexually active woman has been infected with one of the strains the vaccine protects against increases as a woman has more partners, those who didn’t receive the vaccine at the recommended age are still urged to get vaccinated to increase the odds of protection.

Some insurance does not cover the vaccine for those older than 18 — the shots can be costly, though the manufacturer may provide assistance — but it really varies across the board.

October, 2017|Oral Cancer News|

HPV and mouth cancer

Source: www.hippocraticpost.com
Author: Thea Jourdan

hpv

Mouth cancer kills nearly 2000 people in the UK each year. The Human Papilloma Virus (HPV) of which there are over 100 different types, is more commonly associated with cervical cancer and genital warts, but it can also cause oral cancer, particularly of the back of the tongue and tonsils. The virus incorporates itself into the cell’s DNA and causes the cell to multiply out of control, leading to cancer.

In Britain, the number of mouth and throat cancers have increased by 40 per cent in just a decade, to 6,200 cases a year. According to Cancer Research UK, the HPV virus, which is transmitted to the mouth region from the genitals during oral sex, may be key to the ‘rapid rise’. Statistics also show that the more sexual partners you have the greater your chance of acquiring mouth cancer.

“There is now scientific evidence that a proportion of mouth and throat cancers are linked to HPV infection,” says Hazel Nunn, head of health information at Cancer Research UK. “We know that HPV is found in the mouth but we do not yet know how it gets there – whether through oral sex or otherwise. HPV virus has been found on the fingers and elsewhere on the body. It is possible that oral sex is having an impact but more research needs to be done into the kinds of behaviour that leads to this infection.”

“HPV has been causing mouth cancer for decades but the link is only now becoming clear. HPV is a hardy virus that likes sitting in lymphoid tissue wherever it is in the body,” explains Professor Mark McGurk, a senior consultant ENT surgeon based at London Bridge Hospital in London. That means it thrives in the lymphoid tissue in the mouth, including that of the tonsils and at the base of the tongue. For the same reason, it settles in the cervix, the vulva and around the anus.

For many people, HPV won’t cause any problems at all. “In fact, we know that 80 per cent of women and men will have the HPV infection at some time in their lives and clear it themselves without any symptoms,” explains Mr Mike Bowen, a consultant obstetrician and gynacologist based at St John and St Elizabeth Hospital in London. “But for a few it can cause cellular changes that lead to cancer.”

Professor McGurk says that over the last 30 years, he has seen a rise in oropharyngeal cancer, which typically affects sexually active men in their 50s and 60s. “They may have been infected with the virus for some time and ,” he explains. The cancer reveals itself as growths on the tonsils and back of the tongue.

Many patients are only diagnosed at the late stage of their disease. Michael Douglas, the actor, already had stage 4 cancer when his cancer was recognized. Fortunately, oral cancer caused by HPV is very treatable, even when it is very advanced, using radiotherapy. “We used to do surgery on these cases, but we don’t need to anymore. In many cases, the cancer simply melts away with radiotherapy,” explains Professor McGurk. Patients with stage 1 and 2 Oral cancer caused by HPV have an 85 per cent chance of surviving for 5 years after treatment, and patients with stage 4 disease have a 60 per cent chance of surviving five years – impressive compared to the survival rates for other types of oral cancer where overall survival is 50 per cent over 5 years. [Cancer Research UK]

Cancer research UK is pushing for all mouth tumors to be tested to see if they are HPV positive, to assist with effective treatment of patients. “At the moment, it varies massively depending on what hospital you are in. We think it should be standard,” says Hazel Nunn.

Professor McGurk believes there is a simple explanation why men are more likely to have HPV in their mouths than women. “Women harbor the virus in their genitalia which provides a hospitable environment while the male penile area is a relatively hostile area for the virus to settle.”

One way to try and turn the tide would be to introduce a HPV vaccination for boys and girls before they become sexually active. Girls from the age of 12 in the UK have been offered vaccinations since 2008 against the two most common strains of HPV -16 and 18- which are linked to cervical cancer.

Boys are not offered the vaccine, but this should change, according to Professor Margaret Stanley, a virologist based at Cambridge University who believes that boys must be given the vaccine for HPV too from the age of 12 or 13.

‘Obviously cervical cancer is the big one but the other cancers – cancers of the anus and increasingly the tonsil and tongue – there is no screening for them and no way of detecting them until they are proper cancers and they are more common in men than in women.’

Hazel Nunn of Cancer Research UK points out that there is no evidence that vaccinating boys will help protect them from oral cancer. “It is theoretically possible but there have been no trials that had this as an end point. There is a danger that we get too far ahead of ourselves without evidence-based medicine.”

She insists that although HPV is a worrying factor, by far the most significant risks associated with mouth and throat cancers of all types are smoking and alcohol. “

November, 2016|Oral Cancer News|

GlaxoSmithKline pulls Cervarix from U.S. market

Source: www.managedcaremag.com
Author: staff

In response to “a very low market demand,” GlaxoSmithKline has decided to stop selling its human papillomavirus (HPV) vaccine Cervarix in the United States, according to FiercePharma. The move gives Merck’s Gardasil unchallenged dominance of the HPV vaccine market in this country.

Last year, Cervarix earned only about $3.7 million in the U.S. out of a $107 million worldwide total. In contrast, the global total for Merck’s Gardasil franchise was $1.9 billion.

Figures from the Centers for Disease Control and Prevention (CDC) last year placed HPV vaccination rates at 42% of girls and 28% of boys ages 13 to 17 years––far short of the U.S. Department of Health and Human Services’ goal of 80% for both boys and girls by 2020.

To combat the public’s lukewarm response, the CDC and other cancer organizations are urging health care providers to promote the cancer-prevention benefits of HPV vaccines rather than stressing that they protect against sexually transmitted infections, which puts off some parents who worry the vaccine will promote promiscuity or who feel that their preteens are too young to need the shots, according to the Wall Street Journal.

HPV, which is transmitted sexually, can cause at least six types of cancer as well as genital warts. The vaccine is recommended for boy and girls at age 11 or 12 and is also given at other ages.

Experts are urging pediatricians to present the vaccine as routine, rather than different from other preteen shots. They are also stressing completion of the vaccine series by age 13.

Merck, the maker of Gardasil, is currently airing an ad on national television that puts the onus on parents to get their children vaccinated.

Sources: FiercePharma; October 21, 2016; and Wall Street Journal; October 17, 2016.

October, 2016|Oral Cancer News|

HPV symptoms and health consequences

Source: www.kristv.com
Author: Roland Rodriguez

No one dreams of walking into his or her doctor’s office and hearing the words “you have been diagnosed with human papillomavirus, or HPV.” Unfortunately, this scenario is all too real.

HPV is the most common sexually-transmitted infection (STI) in the United States. In fact, it’s so common that nearly all sexually active men and women get it at some point in their lives.

There are over 100 different kinds of HPV but only some of them can cause serious health problems like genital warts or cancer of the cervix, vagina, vulva or anus.

Testing positive for HPV does not automatically mean you will get cancer. Some studies estimate that 50 percent of those infected with HPV will clear the virus within eight months— and 90 percent will be cured within two years. It’s only when your immune system isn’t able to fight off the infection that some strains of HPV can persist and possibly lead to cancer.

The number of human papilloma virus (HPV)-associated cancers in the United States has increased by 17 percent, to nearly 39,000 cases a year, according to a report released from the Centers for Disease Control and Prevention.

While men cannot get HPV-linked cervical cancers, they are particularly vulnerable to HPV-related cancers of the mouth, tongue and throat, called oropharyngeal cancers. According to the new CDC report, the rates of mouth and throat cancers are more than four times higher among males than females.

In the past, people always felt that the boys needed to be vaccinated to protect the girls but, truthfully, the most effective way to prevent HPV: early vaccination.

Boys and girls are supposed to get three doses of the HPV vaccine — starting at age 11 or 12 because the vaccine works best before sexual activity begins.

The other benefit of giving it early is that our immune response is better, and that it may last longer.

Yet the latest statistic from the CDC shows that in 2014, only 40 percent of teenage girls received all three doses of the vaccine needed. In boys, that number is even lower: Only 22 percent of boys between 13 and 17 are properly vaccinated against HPV, increasing their chances for HPV-caused cancers later in life.

According to the CDC, the HPV vaccine — which is usually covered by insurance — is safe and not associated with serious side-effects of the HPV.

What are the signs, symptoms and health consequences of HPV?

In most cases, HPV goes away on its own and does not cause any health problems. But when HPV does not go away, it can cause health problems like genital warts and cancer.

Genital warts usually appear as a small bump or groups of bumps in the genital area. They can be small or large, raised or flat, or shaped like a cauliflower. A healthcare provider can usually diagnose warts by looking at the genital area.

Cervical cancer usually does not have symptoms until it is quite advanced, very serious and hard to treat. For this reason, it is important for women to get regular screening for cervical cancer. Screening tests can find early signs of disease so that problems can be treated early, before they ever turn into cancer.

Other HPV-related cancers might not have signs or symptoms until they are advanced and hard to treat. These include cancers of the vulva, vagina, penis, anus, and oropharynx (cancers of the back of the throat, including the base of the tongue and tonsils.

September, 2016|Oral Cancer News|

Why men need to start caring about HPV

Source: www.refinery29.com
Author: Sarah Jacoby

The human papillomavirus (HPV) is one of very few STIs that we have a vaccine for. And — bonus! — that vaccine prevents cancer. But a report from the U.S. Centers for Disease Control and Prevention (CDC) released last month indicated that although we’ve made some improvements in the vaccination rates, they still aren’t where we want them — especially for boys. This is despite the fact that pretty much everyone who’s sexually active will get the virus at some point and men are at risk for their own unique set of HPV-related health consequences.

Let’s start with the basics: “HPV is a virus that’s sexually transmitted, but it’s incredibly common,” explains Kathleen Schmeler, MD, of the University of Texas MD Anderson Cancer Center. Up to 80% of people get it at some point in their lives, she says, which is why some doctors refer to it as the “common cold” of STIs. For most people, the virus goes away on its own, without causing symptoms or needing treatment. Some people develop genital warts that can be treated with medication. But in some rare instances, the virus can go on to cause more serious health issues — including some types of cancer.

“The problem is we don’t know who’s going to clear it and who won’t,” Dr. Schmeler says. Most notably, HPV is known to cause cervical cancer. In fact, nearly all cases of cervical cancer are attributed to HPV. In 2013, the most recent year with available data, almost 12,000 women were diagnosed with cervical cancer in the U.S. and about 4,200 women died from the disease.

In addition to the risks of passing on the virus to their partners, men may face other consequences of HPV. Some types of HPV-related cancer, including throat cancer, are actually more common among men than women. “The rates for that are increasing significantly,” says Dr. Schmeler. “That’s been a huge deal recently.”

However, there is currently no accepted test for HPV-related cancers in men. Women are recommended to get a routine Pap screening, which can detect abnormal cervical cells that may be a result of an HPV infection. But similar screening for anal, penile, and throat cancers in men isn’t recommended.

“The common story that we hear is that [men are] shaving and they find a big lump in their neck,” says Dr. Schmeler. “But by then, it’s advanced disease because it’s spread to the lymph nodes.”

So although Dr. Schmeler’s team is working to find one, there’s no early or precancerous-stage test to detect HPV-related cancer in men.

Because they can’t be tested, it’s that much more important for boys to get the vaccine. Currently, the vaccine is recommended for boys and girls ages 11 to 12 to make sure they get it before they come in contact with the virus. But according to that August report, only about 50% of boys and 63% of girls actually got the vaccine in 2015. While the rates are improving quickly, they’re still nowhere near where they should be.

So why is it that the already-low vaccination rate is even lower for boys than girls? Part of that appears to be due to the way the vaccine was originally marketed: “When it first came out [in 2006], it was recommended only for girls because the primary focus was cervical cancer,” explains Dr. Schmeler. Since then, the CDC has expanded its recommendations to include boys, too. Parents may simply be unaware of the update.

According to research from the CDC, another big problem is that parents don’t believe their kids are (or are about to be) sexually active at that age. Doctors may be reluctant to push the issue or, in some cases, even bring it up.

“Everyone’s so obsessed with the fact that it’s a sexually transmitted disease,” says Dr. Schmeler. “[And in the process, we’re] forgetting that, with this vaccine, we can prevent cancer.”

It may be too late for adult men to get the most out of vaccination — it’s recommended that everyone get the vaccine by age 26. But for it to be it’s most effective, you should ideally get the vaccine before you’re exposed to the virus. And if you’ve already had multiple sexual partners, it’s likely that you’ve already been exposed.

But that doesn’t mean men don’t have to worry about this. In addition to the risk of spreading the virus to their partners, men are at risk for various cancers, as well. The bottom line is that HPV affects everyone, so we should all be equally sharing the burden of stopping the virus — and its associated cancers.

September, 2016|Oral Cancer News|

Despite medical backing, HPV vaccine rates remain low amid sexual and moral controversy

Source: www.omaha.com
Author: Rick Ruggles, World-Herald staff writer

pharynx_cancer

The HPV vaccine can reduce the rates of certain cancers, including many cervical and oral cancers, physicians and medical organizations say. But opposition by some individuals is strong, and HPV vaccination rates remain low when compared with other kinds of vaccinations recommended for adolescents.

Because the human papillomavirus is sexually transmitted and seventh grade is considered the ideal time to receive the three-dose vaccine regimen, the issue is rife with sexual and moral implications. Perhaps more potent today, though, are Internet horror stories and concerns about side effects.

A World-Herald Facebook request for views on the HPV vaccine generated far more negatives than positives. “NO NO & NO!! There is NO reason for this vaccine,” one wrote. Another called it a “deadly shot.”

Two Omaha mothers who were interviewed expressed their belief that it’s wise to have children vaccinated, and said their kids suffered no side effects. But an Iowa man described health problems suffered by his daughter, and he and an Ohio physician believe the girl was injured by the HPV vaccinations.

So mediocre are HPV vaccination rates that GSK, the maker of Cervarix, plans to cease distribution of its HPV vaccine in the United States in September. It will continue to supply it in many other nations, such as Great Britain, Germany, France and Mexico. The departure of Cervarix leaves the market to Gardasil, a vaccine produced by Merck.

“GSK has made the decision to stop supplying Cervarix … in the U.S. due to very low market demand,” the company told The World-Herald last week by email.

Many doctors in the Omaha area express disappointment with the low HPV vaccination rates but are optimistic that the situation will improve.

“As pediatricians, we’re trying to change that,” said Dr. Katrena Lacey, a Methodist Physicians Clinic pediatrician in Gretna. “I think we’re on the right track.”

A survey of adolescents reported last year by the federal Centers for Disease Control and Prevention found that 39.7 percent of girls ages 13 to 17 had received the three-dose regimen of the HPV vaccine in 2014, and 21.6 percent of boys.

This compares with 87.6 percent of boys and girls who had received the tetanus-diphtheria-pertussis vaccination and 79.3 percent who had received the meningococcal vaccine.

Dr. Megann Sauer, a pediatrician with Boys Town Pediatrics, said parents accept use of the vaccine if it’s explained well and described as a cancer-prevention strategy. “It’s a huge responsibility for us as providers to offer this to our patients,” Sauer said. “My job is to keep my patients healthy.”

Gardasil was approved in the United States 10 years ago. It was met with concern that having a child vaccinated for HPV, which is the most common sexually transmitted infection, would promote promiscuity.

Today, the global Christian ministry Focus on the Family says it “supports universal availability of HPV vaccines,” but it opposes government-mandated HPV vaccinations for public-school enrollment. The mandates are in place in Virginia, Rhode Island and Washington, D.C.

Tom Venzor of the Nebraska Catholic Conference said the vaccine itself isn’t morally problematic. But “the promotion of chastity and parental consent should never be undermined in the promotion of the HPV vaccine,” Venzor said in an email.

The Kaiser Family Foundation estimates that there are more than 14 million new human papillomavirus infections annually in the U.S. Most resolve on their own, but some chronic HPV infections can embed in tissues and lead to cervical cancers and tongue, tonsil, anal, vulvar, vaginal and penile cancers.

The American Cancer Society estimated there will be close to 13,000 new cases of cervical cancer this year and 4,120 deaths. HPV was detected in more than 90 percent of cervical cancers, a 2015 study reported in the Journal of the National Cancer Institute said.

“If you’ve ever seen anyone die of cervical cancer, it will tear you apart, because it’s a nasty, nasty disease,” said Dr. Steve Remmenga, a specialist in gynecologic oncology at the University of Nebraska Medical Center. Remmenga advocates getting the vaccination.

The CDC recommends routine HPV vaccinations beginning at 11 or 12 years of age for girls and boys, but the series can start as early as 9 years of age. The second dose should be given a month or two later and the third at least six months after the first. The vaccinations may be completed by 26 years of age. The recommendations have been adopted by the American Cancer Society and other medical organizations.

The recommendations suggest children receive the vaccinations “so they are protected before ever being exposed to the virus,” the CDC said. The agency said clinical trials indicate the vaccination provides “limited or no protection” against HPV-related diseases for women older than 26.

The CDC says the vaccine has repeatedly been shown to be safe.

Kari Nelson, a biology instructor at the University of Nebraska at Omaha, said two of her daughters, Claire and Emma, have had the full regimen and her third daughter, Gretchen, is about to get her second shot.

“I definitely believe in protecting my kids as much as possible,” Nelson said. “I do always try to weigh the pros and cons of anything. I just feel that the pros far outweigh the cons in this case.”

The Nelsons’ pediatrician, Dr. Tina Scott-Mordhorst, supports children and adolescents receiving the HPV vaccine. Why, she asked, would anyone not get a shot that might prevent cancer? “It works,” said Scott-Mordhorst, a clinical professor in UNMC’s department of pediatrics.

A study reported this year in the journal Pediatrics found that among sexually active females ages 14 to 24, the prevalence of four key HPV types was 16.9 percent among the unvaccinated and 2.1 percent among the vaccinated.

Scientists say it can take many years for chronic HPV to turn cancerous.

Dr. Bill Lydiatt, a head and neck cancer surgeon at Methodist Hospital, said oral sex and the sexual revolution of the late 1960s have contributed to an increase in cancers of the pharynx, or tonsil and back of tongue. The cancer society reported there will be 16,420 cases of cancer of the pharynx this year, most of them in men, compared with 8,950 in 2006. More than 3,000 will die this year from that kind of cancer, the society says.

Lydiatt said scientists only about 10 years ago made the clear link between HPV and cancers of the pharynx and tonsils.

There are more than 150 strains of HPV and more than 40 that can cause cancer, the Kaiser Family Foundation reported. The first form of Gardasil protected against four strains, including the two believed to be most prevalent in cancers. Two years ago the FDA approved a Gardasil vaccine that protected against nine strains. The study in the Journal of the National Cancer Institute says that “current vaccines will reduce most HPV-associated cancers.”

The vaccines are expensive. The Gardasil nine-strain vaccine is close to $250 per dose at Kohll’s Pharmacy if a family pays out of pocket. But many insurers, such as Blue Cross Blue Shield of Nebraska, Aetna/Coventry and UnitedHealthcare, participate in the payment.

A Merck spokeswoman said GSK’s decision to cease supplying Cervarix to the U.S. market hasn’t affected Gardasil prices as of now. An Omaha pharmacist said it wouldn’t be unusual to see prices go up with the departure of a competitor. “The reality is that they can,” Mohamed Jalloh said. “I’m not saying they’re going to.”

Merck has applied to the Food and Drug Administration to market a two-dose regimen of Gardasil, which would reduce the overall price of the series.

Facebook posts and the Internet contain scathing reviews of Gardasil, including stories of children being hurt and families being scared of the vaccination.

Laura Hansen, a cancer researcher at Creighton University, said she wishes she could find the words to persuade people to get their kids vaccinated.

“About all of us have family members impacted by cancer,” said Hansen, a professor of biomedical sciences. By having their kids vaccinated, she said, “Every parent could make an impact on cancer deaths.”

She said it’s hard to fight Internet scare stories and “anecdotal science” as opposed to real science and legitimate studies. The discussion should be “more about facts and less about hysteria,” said Hansen, who saw to it that her two teen-age sons, Charlie and Jack, were vaccinated.

Jeff Weggen of Muscatine, Iowa, has an entirely different view. Weggen said his daughter, Sydney, had the vaccines about four years ago. Soon after, she began to lose weight, suffered back pain and became pale. Over a period of months she was hospitalized and saw specialists in state and out-of-state. She was eventually found to have a fungal infection and a large tissue mass in her chest.

Weggen eventually linked Sydney’s ongoing medical problems to Gardasil, he said. Online groups, other parents and the timeline of her vaccines and her illness helped lead him to this opinion, he said. An anti-Gardasil Facebook post introduced him to a doctor in Ohio who early this year generally confirmed Weggen’s suspicions.

Dr. Phillip DeMio of the Cleveland area said he has several patients he believes were sickened by Gardasil. DeMio, a general practitioner who said his practice focuses on chronically ill people, said some of his patients have been injured by other vaccines, too.

“These are challenging situations, no two ways about it,” he said. Most people have received a variety of vaccinations, he said, and he believes the aluminum in Gardasil and other vaccines can be a problem for some people.

He saw Sydney early this year. Based on the extensive testing that ruled out other diseases, the severity of her illness, the timing of vaccination and other factors, he said he believes “there’s a component of vaccine damage for her and for many of my patients.”

He said there are good reasons to have an adolescent receive Gardasil and mentioned the likelihood that some individuals will be sexually active. But it makes no sense to have a 9-year-old get it, he said. He said parents should be well-informed of the risks and benefits of Gardasil and other vaccines.

“I think people should have a choice,” he said. “I’m not saying I’m against the vaccine.”

The CDC sent a written statement saying that millions of doses of Gardasil have been administered.

Scientific studies have detected no link to “unusual or unexpected adverse reactions,” the CDC said.

Side effects can include pain from the shot and occasionally a patient might faint after any injectable vaccine, the CDC said. But “the benefits of vaccination far outweigh any risks.”

HPV vaccination could be offered to schoolboys to decrease risk of cancer

Source: www.mirror.co.uk
Author: Andrew Gregory

A vaccination could soon be offered to every schoolboy to help tackle the rising rate of some cancers in men, a Government minister revealed on Thursday. Health chiefs are poised to drop their opposition to extending the jab to protect against the human papilloma virus (HPV), which is already given to all Year 8 girls. The likely move follows growing alarm over cancers of the mouth, throat, neck and head, as well as penile and anal cancer, amid growing evidence that they are caused by HPV.

The NHS (National Health Service) spends more than £300m a year treating head and neck cancers, while giving the vaccine to all boys would cost just £22m, supporters say.

Health Minister Jane Ellison has revealed that the independent Joint Committee on Vaccination and Immunization (JCVI) is investigating the change, with its verdict due early next year. Mrs Ellison – who has previously described giving the HPV jab to girls only as “a little odd” – said: “I understand the wish for it to be available to all adolescents regardless of gender.

“The JCVI is reconsidering its initial advice on this and modeling is under way to inform its consideration. We will look at that as a priority when we get it.

“I recognize the frustration that people have expressed and I have talked personally to Public Health England officials who are involved in the modelling work.”

The minister said money was already available to extend the vaccination program if the JCVI said yes, adding: “The Government have always acted on its recommendations.” The looming move comes after a Commons debate heard that men are six times more likely than women to have an oral HPV infection – yet they are not vaccinated.

Conservative MP Sir Paul Beresford , a part-time dentist himself, said up to 70% of throat cancers are caused by HPV, adding: “The statistics make for hideous reading.”

HPV is also linked to around 80% of anal cancer in men, almost half of penile cancers and is responsible for nine out of 10 cases of genital warts. A national vaccination program HPV was introduced for 12 and 13-year-old girls as long ago as 2008, to prevent cervical cancer.

But experts agree the program does not create sufficient “herd immunity”, prompting a recent decision to begin a trial to give the jab to some gay men. Around 40,000 men who have sex with men (MSM) will be vaccinated, targeting under-45s who attend sexual advice clinics.

A campaign group called HPV Action has called for all boys to be vaccinated as soon as possible – warning 367,000 are at risk of developing a preventable disease in later life, for every year of delay.

ASCO Urges Aggressive Efforts to Increase HPV Vaccination

Source: www.medscape.com
Author: Zosia Chustecka
 

Human papillomavirus (HPV) vaccines have now been available for 10 years, but despite many medical professional bodies strongly recommending the vaccine, uptake in the United States remains low.

Data from a national survey show that about 36% of girls and 14% of boys have received the full schedule of HPV vaccines needed to provide protection (Vaccine. 2013;31:1673-1679).

Now the American Society of Clinical Oncology (ASCO) has become involved, and in a position statement issued today the organization calls for aggressive efforts to increase uptake of the HPV vaccines to “protect young people from life-threatening cancers.”

“With safe and effective vaccines readily available, no young person today should have to face the devastating diagnosis of a preventable cancer like cervical cancer. But unless we rapidly increase vaccination rates for boys and girls, many of them will,” ASCO President Julie M. Vose, MD, said in a statement.

“As oncologists, we see the terrible effects of these cancers first hand, and we have to contribute to improving today’s alarmingly low vaccination rates,” she added.

The new policy statement is published online April 11 in the Journal of Clinical Oncology.

The statement notes that HPV vaccination has been previously recommended by many US medical societies, including the American Cancer Society, the American College of Obstetrics and Gynecology Committee, the American Dental Association, the American Head and Neck Society, the American Nurses Association, the American Pharmacists Association, the Association of Immunization Managers, the Society for Adolescent Medicine, and the Society of Gynecologic Oncology.

In addition, a joint letter was sent out to all physicians urging them to give a strong recommendation from the American Academy of Family Physicians, the American Academy of Pediatrics, the American College of Obstetricians and Gynecologists, the American College of Physicians, the Centers for Disease Control and Prevention, and the Immunization Action Coalition.

Now oncologists are specifically being asked by their professional body, ASCO, to join in with the push toward greater uptake of the HPV vaccines.

“ASCO believes oncologists can play a vital role in increasing the uptake of HPV vaccines,” the new policy statement says. “Although most oncologists will not be direct providers of these preventive measures, this does not abrogate us from contributing to this process. Our unassailable role in the mission to lessen the burden of cancer…places us in a position of influence. We should use interactions with our patients, primary care colleagues, and health care systems to raise awareness of HPV-related cancers and the role of vaccination in preventing them.”

Oncology providers have a responsibility to serve as community educators.

“Oncology providers have a responsibility to serve as community educators, disseminating evidence-based information to combat misconceptions concerning the safety and effectiveness of the HPV vaccine,” it continues.

“ASCO encourages oncologists to advocate for and actively promote policy change to increase vaccination uptake,” the statement concludes.

Issues With the Statement

However, there are a few issues with the statement, says a prominent researcher in the field of HPV and cervical cancer, Diane Harper MD, professor and chair of the department of Family and Geriatric Medicine, University of Louisville, Kentucky. Dr Harper, who was approached for comment, was involved in early clinical trials with both HPV vaccines (Gardasil, Merck & Co, and Cervarix, GlaxoSmithKline), and has emphasized the need for ongoing screening with Pap tests to prevent cervical cancer.

This is also one of the issues she raises about the ASCO statement, which does not mention screening. “All messages about HPV vaccination must be couched in terms of continued lifetime screening for cervical cancer,” Dr Harper told Medscape Medical News.

The ASCO statement highlights the potential that HPV vaccination has for preventing cancer. (Both vaccines protect against HPV types 16 and 18, and Gardasil offers additional protection against several other types). The statement notes that HPV is the cause of nearly all cervical cancer cases and that HPV genotypes 16 and 18 are responsible for 70% of cervical cancers. In the United States, HPV is responsible for 60% of oropharyngeal cancers, 90% of which are caused by HPV 16. HPV is also the cause of 91% of anal cancers, 75% of vaginal cancers, 69% of vulvar cancers, and 63% of penile cancers, again with HPV 16 as the predominant oncogenic genotype.

However, the statement also notes that “because of the long latency and the prolonged preinvasive phase after infection with HPV, many years of follow-up are needed for the ongoing trials to demonstrate a significant reduction in HPV-related cancers.”

Therefore, intermediate outcomes are being used as surrogate endpoints, it continues. HPV vaccines have been shown to prevent new cancer-causing HPV genotype-specific infections and resultant diseases, such as grades 2 and 3 cervical intraepithelial neoplasias (CIN), vaginal, vulvar, and anal intraepithelial neoplasias (as precursor lesions to cancer).

There is “almost certainty that cancers caused by oncogenic HPV genotypes will be dramatically reduced,” according to the statement.

Dr Harper told Medscape Medical News that the studies conducted to date have shown that “Cervarix has a 93% efficacy against CIN 3 regardless of HPV type; Gardasil has a 47% efficacy against CIN 3 regardless of HPV type, and Gardasil 9 is equivalent to Gardasil in the prevention of CIN 3 disease regardless of HPV type. None of these vaccines can prevent all CIN 3 or potentially all cancers.”

“Hence, the most important take home point is that screening is absolutely necessary as a prevention tool for preventing cancer by early detection of disease that when found, is curable,” Dr Harper emphasized.

Also, Dr Harper noted that the studies ended at prevention of CIN 2/3 disease as a clinical outcome. CIN 3 on average progresses to cancer in 20% of women within 5 years, and to 40% of women in 30 years. But, she points out, “there are no long-term follow-up studies that show that cancers will be averted.”

“The modeling exercises indicate that we have to wait at least 40 years before we will have a detectable decrease in cervical cancers from vaccination, assuming that at least 70% of the population being surveyed is vaccinated,” she added.

In its statement, ASCO cites the success of widespread vaccination against hepatitis B virus in reducing the incidence of liver cirrhosis and liver cancer as “an exemplary health model that supports more widespread HPV vaccination.”

But Dr Harper argues that “the prevention of liver cancer was an unexpected highlight of HBV vaccination. The primary purpose was to relieve the symptoms of chronic HBV sufferers. The continual re-infection with HBV seems to allow a natural infection to act as a booster in this population, which may not be the same for HPV.”

There also remains a question of how long the protection offered by HPV vaccination will last.

The ASCO statement says, “Both vaccines have a known duration of protection of at least 5 years, with ongoing study of the full duration of their effect,” and it notes that “additional research is needed to evaluate duration of protection to determine if booster doses are required.”

Dr Harper said, “Estimates of long-term effectiveness are based on antibody titers, yet there is no surrogate of protection defined by antibody titers.”

She added: “I agree that observational studies will inform the public health authorities about when a booster will be needed and whether it is needed sooner if only 2 doses are received vs later if 3 doses​ are received.”

Last, but not least, there is the issue of safety.

The ASCO statement notes that both Gardasil and Cervarix “reported excellent short- and long-term safety results in clinical trials. The most common adverse effects were mild and included injection site pain (approximately nine in 10 people) and swelling (approximately one in three), fever (approximately one in eight), headache, and fatigue (approximately one in two). These symptoms were transient and resolved spontaneously. The incidence of serious adverse effects was low and was similar to those who received placebo (aluminum-containing placebo or hepatitis A vaccine).”

However, worldwide there continue to be reports of adolescents who report chronic side effects and pain syndromes after being vaccinated against HPV. Some of these have been documented in the medical literature, with physicians reporting instances of previously healthy athletic girls becoming incapacitated with pain, fatigue, and autonomic dysfunction, and some remaining permanently disabled.

The US Food and Drug Administration and the Centers for Disease Control and Prevention have repeatedly said that HPV vaccines have an excellent safety record and that no causal associations have been found with atypical or unusual pain syndromes or autonomic dysfunction. The European authorities have investigated two chronic syndromes reported with HPV vaccination, and have said that there is no evidence to show causation.

However, Danish researchers who were among the first to report these syndromes criticized the investigation and are conducting their own study. There have also been lawsuits filed in several countries, and a class action lawsuit is now planned in Japan against the government and the vaccine manufacturers.

In an interview with Medscape Medical News, lead author on the ASCO statement, Howard H. Bailey, MD, from the University of Wisconsin Carbone Cancer Center, Madison, said that the concerns over safety should not be dismissed and should be studied further.

These issues need to be studied further, even if the authorities say that the vaccines are safe, he emphasized. These reports of girls becoming very ill, having pain syndrome and weakness, should not be diminished, he said, adding: “We can’t just ignore these reports…if there is risk involved, then that needs to be sorted out better.”

However, there is always a possibility that the syndromes and side effects that have been reported “have nothing to do with the vaccine,” Dr Bailey commented, citing the case of now-discredited theory linking autism to the pediatric vaccine for measles, mumps, and rubella.

There may be other explanations for the symptoms that are reported, or it could be that the symptoms/syndrome would have developed in the individual, anyway, but the vaccination precipitated it sooner, he suggested.

Dr Bailey noted that across the United States physicians are very sensitive to the fact that rates of pediatric vaccination have gone down because of the link that had been made to autism, subsequently shown to be false. Even though science eventually showed no link between the vaccine and autism, public confidence in the vaccine was damaged.

“When a person’s life has been devastated by an illness, that is very important, but if it turns out that the illness is not related to the vaccine, and in the meantime, the concerns over safety have stopped thousands of young people from being vaccinated….”well, eventually this will mean that there are more people who die from cancer, he said.

“I would be very reluctant right now to shut down the goals of vaccination over what has been reported, because the bottom line is that we have a tremendous problem with the rising incidence of HPV related cancers including in men as well as women when it comes to oropharyngeal cancers here in the States,” he added.

“The data, at least in my opinion, are so strong that HPV vaccination if it’s done in a [systematic] way will reduce the incidence of these cancers…I don’t want to stop whatever progress we are making when there is at best disagreement over whether these things are associated,” he said, although he also added that “maybe if it was my daughter, I would feel differently.”

Dr Bailey also addressed some of the other issues that had been raised about the ASCO statement, and said he agreed about the importance of screening.

“Even if vaccination does all the things we expect it to do, there is no doubt that cervical cancer screening needs to continue, and that’s a pretty standard recommendation across all of the groups,” he said. “We do not mean to diminish the importance of continued screening,” he said, but he added that screening lies in the domain of other physicians, such as primary care and gynecology, whereas this statement was targeted specifically at oncologists. “To take a step back, we are taking the view of cancer physicians, who take care of women, who are unfortunately too often dying of cervical cancer, and…we wanted to remind people that HPV vaccination can prevent this…as well as other associated cancers,” he said.

“The audience in North America has not been paying attention to this vaccination issue very much,” he continued, and “we wanted to remind oncologists and the public that at the heart of the issue is cancer prevention.

“We have this relatively easy way of preventing cancers over and above the ways that we already use,” he added.

“We wanted to remind people, especially in the oncology community, that there is this intervention out there that we think is highly, highly likely — if applied and used in a population format — will significantly reduce the number of women dying of cervical cancer, the number of men and women dying from oropharyngeal cancer, which is increasing in the US…and that was the main focus of the article,” Dr Bailey commented.

*This news story was resourced by the Oral Cancer Foundation, and vetted for appropriateness and accuracy.

April, 2016|Oral Cancer News|