Tag Archives: immunization

STD Awareness: Searching for an HIV Vaccine

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Ever since the dawn of the AIDS era, researchers have worked nonstop to develop an HIV vaccine. In 1984, Margaret Heckler of the U.S. Department of Health and Human Services famously (over)promised that a vaccine would be ready for testing in two years. But it’s taken much, much longer. This Saturday, May 18, is HIV Vaccine Awareness Day, a celebration of the patients, community members, and scientists who are hard at work bringing this vaccine into existence.

Only one vaccine — still in the experimental stage — has shown any effectiveness against HIV.

Hiding from the Immune System

Vaccines are inspired by our own bodies’ ability to fight disease. Usually, when our immune system encounters a threat, it takes note of the viral “antigens,” which are like facial features — a button nose, say, or dramatically arched eyebrows — that make it instantly recognizable. It creates “antibodies,” weapons that can target those antigens like guided missiles. Often, the immune system can remember the distinguishing facial features so it’s ready to attack if the enemy ever returns — giving us immunity, possibly for life.

Vaccines take advantage of our natural ability to create these immune memories by exposing our immune systems to antigens without actually exposing us to infectious viruses. Think of it as a “wanted” poster that helps the immune system recognize “bad guys” before it actually sees them on the street, enabling it to attack and destroy them before they cause disease. Continue reading →

STD Awareness: The Long Road to a Chlamydia Vaccine

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Earlier this year, television personality John Oliver was the butt of an elaborate prank orchestrated by actor Russell Crowe. It started with an auctioned jock strap, and ended with Crowe funding the John Oliver Koala Chlamydia Ward at the Australia Zoo. If you want the full story, check out the video below (beware explicit language).

Despite Oliver playing it for laughs, koala chlamydia is very real and very serious. At least half of wild koalas are infected with a chlamydia type that’s related to the human version. As in humans, koalas can transmit these bacteria through sexual contact. And, similar to the havoc it wreaks in our species, in koalas chlamydia can cause blindness, urinary tract infections, and female infertility — and can be passed from mother to infant. Along with other factors, chlamydia is said to be responsible for plummeting koala populations in many parts of Australia. Continue reading →

STD Awareness: Can Older Adults Receive the HPV Vaccine?

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female-patient-with-female-doctorWhen the human papillomavirus (HPV) vaccines were introduced, a lot of people were excited about protection from a sexually transmitted virus that could cause cancers, including cervical cancer, anal cancer, and head-and-neck cancer. It wasn’t just any old vaccine, it was a shot that could prevent cancer. Cancer!

In fact, a lot of people were disappointed they were too old to take advantage of an anti-cancer vaccine, which was initially approved for people as old as 26. We were given a lot of reasons why people above that age were “too old,” such as the assumption that anyone older than 26 has probably been sexually active for years and would have already contracted the most common strains of HPV.

While getting vaccinated before becoming sexually active is optimal, the HPV vaccine can still benefit people who have already had sex.

But there are compelling reasons to vaccinate people in their late 20s and beyond. In fact, Gardasil 9 was recently approved for people as old as 45. That’s great news for those of us who missed out on the HPV vaccine the first time around. We might never have had any sexual contact, and therefore were never at risk for catching the sexually transmitted virus. We might have found ourselves widowed or divorced after years or decades of monogamy. We might have been sexually active with multiple partners during that time. Whatever our circumstances, those of us who are 45 or younger can now consider HPV vaccination.

HPV and the “Older” Individual

When Cervarix and Gardasil, the first HPV vaccines, were released, they only protected against two cancer-causing HPV strains, HPV-16 and HPV-18, which are responsible for 70 percent of cervical cancers (Gardasil protects against two additional wart-causing HPV strains). A few years ago, Gardasil 9 hit the market, targeting five additional cancer-causing HPV strains — increasing the chances that even sexually active recipients could be protected from HPV strains they hadn’t encountered. Continue reading →

STD Awareness: Eliminating HPV-Related Cancers

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Earlier this month, every major cancer center and organization in the country released a joint statement calling for the elimination of cervical cancer, along with all other HPV-related cancers. The elimination of a large swath of cancers might sound like a tall order — so far, we’ve only eradicated two viruses from the planet: smallpox and rinderpest. And we’re on the brink of getting rid of a third, the virus that causes polio.

But doing away with human papillomavirus (HPV) would herald a new chapter in disease eradication, because HPV causes cancer, meaning that eradicating HPV will eradicate the cancers caused by it. And the good news is we have all the tools we need to wipe HPV off the face of the earth — we just need to use them.

The tools to wipe a large class of cancers off the face of the earth are right under our noses — we just have to use them.

A quick rundown on HPV is in order. It’s the most common sexually transmitted infection in the world, and causes multiple cancers — cervical, head and neck, anal, vulvar, vaginal, and penile. While it’s most well-known for causing cervical cancer, here in the United States it is transitioning away from its old job, causing more head-and-neck cancers than cervical cancers. Nearly all sexually active people will be infected with HPV at least once in their lives, and though only a fraction of infections progress to cancer, its ubiquity means it still causes hundreds of thousands of cancers every year. In the United States, around 41,000 HPV-related cancers are diagnosed annually, while more than 600,000 are diagnosed worldwide. Continue reading →

STD Awareness: Fighting Cervical Cancer Across the World

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Tomorrow kicks off World Immunization Week, a reminder that, just as disease can cross borders, so should our efforts to prevent it. Especially when we have an effective vaccine for one of the world’s top causes of cancer — but the people who need it most are less likely to get it.

Almost 90 percent of cervical-cancer deaths strike women in developing countries, where it is the second-most common cancer among women. In fact, over vast swaths of Africa, cervical cancer is the No. 1 cause of cancer death in women. (In the United States, it doesn’t even crack the Top 10.) While cervical cancer rates are holding steady in the developed world, in the coming decades they are projected to increase sharply in less developed regions.

More than 9 out of 10 cervical cancers strike women in countries with no HPV vaccination programs.

Since 2006 there has been a vaccine for human papillomavirus (HPV), the virus that causes cervical cancer. Unfortunately, while this vaccine is making impressive strides in the developed world, it is almost out of reach in the developing world, where it could save the most lives. To fully realize this vaccine’s potential, it needs to be distributed worldwide — not just within rich countries that can afford it.

Fighting Cervical Cancer in the Developed World

HPV has been nicknamed “the common cold of STDs” — because pretty much every sexually active person will get it at some point. It can be transmitted by vaginal, anal, and oral sex, as well as by rubbing genitals together, even without penetration. HPV can cause cancers of the throat, anus, vagina, vulva, and penis — but is most “famous” for causing cancer of the cervix (the tissue that connects the vagina to the uterus). If you have a cervix, there are two big things you can do to protect its health: receive regular Pap testing after becoming sexually active, and get vaccinated against HPV before becoming sexually active. When you take both of these steps, you’ll maximize what modern medicine has to offer. Continue reading →

STD Awareness: Is HPV Now a “Men’s Disease”?

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Human papillomavirus, or HPV, is most notorious for causing cervical cancer — making it, in many people’s minds, a “women’s disease.” But this gender-blind sexually transmitted virus can cause cancer in any cell it infects, and is associated with cancers of the cervix, anus, vagina, vulva, penis, and mouth and throat — aka oropharyngeal cancer.

While oropharyngeal cancers used to be caused mostly by tobacco, as people quit smoking an increasing proportion is caused by HPV. In the 1980s, only 15 percent of oropharyngeal cancers were caused by HPV, but nowadays the virus is behind 70 percent of them. A 2011 study predicted that the number of HPV-positive oropharyngeal cancers will surpass cervical cancers by 2020.

HPV is rapidly gaining prominence among men.

It’s only 2017, but we’re ahead of schedule. Earlier this year, researchers reported that, in the United States, oropharyngeal cancer is more common among men than are cervical cancers among women — and oropharyngeal cancer rates are increasing in the male population, while they are relatively stagnant among women. These rates are projected to continue climbing, which will skew oropharyngeal cancer even more heavily toward the male population. But, in the public’s imagination, HPV is most well-known for its association with cervical cancer — while most people haven’t even heard of oropharyngeal cancer.

Oropharyngeal Cancer and HPV

Oropharyngeal cancer can strike the inside of your mouth and throat. Risk factors include tobacco (including cigarettes, snuff, and chewing tobacco), marijuana use, alcohol, and oral infection with HPV. HPV can be spread by most sexual activities — including vaginal, anal, and oral sex, as well as “French kissing” and rubbing genitals together. There are many strains of HPV, which come in two main categories: low-risk HPV, which can cause genital warts; and high-risk HPV, which can cause cancer. Continue reading →

Some Good News About Three Sexually Transmitted Viruses

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Scientists are hard at work finding ways to improve your health!

With so much bad news emblazoned across headlines in every newspaper you look at, the world might seem like a gloomy place. So let’s take one depressing subject — disease — and peel away the sad outer layer to find silver linings of optimism.

When it comes to infections, a lot of us blame one thing: germs, also known as “bugs” — “pathogens” if we’re fancy. Some people might not think of infectious diseases as being that big of a deal — after a round of antibiotics, you’ll be on the mend. Unfortunately, antibiotics only work for bacteria, but a lot of diseases are caused by other types of germs — for which antibiotics are no match. One type of germ is called a virus, and they can’t be cured. Sometimes they can be prevented with vaccines or treated with drugs. For example, the major strains of human papillomavirus (HPV) can be prevented with a vaccine called Gardasil, herpes simplex virus can be suppressed with antiviral drugs, and HIV can be controlled with antiretroviral drugs — but none of these infections can be cured. HPV is usually defeated by the immune system, but herpes and HIV are with you for life.

But it’s not all bad. Around the world, individual scientists have picked their “favorite” viruses and are devoting their lives to finding better prevention strategies, better treatments, and even cures. Let’s check in with some of the latest headlines touting the successes of science.

New Hope for a Herpes Vaccine

A herpes vaccine would be a blockbuster — given how common this sexually transmitted infection is, a preventive shot could help a lot of couples discuss their herpes status without as much fear of judgment and stigma.

Herpes might cause an “outbreak” — unpleasant symptoms that include genital sores — but afterward the virus goes dormant in the nerve cells, hiding from the immune system. In some people, the virus can come out of its dormancy to cause flare-ups of symptoms, but once it’s had its fun it retreats back to the nerve cells.

Earlier this year, media reported on a promising new candidate for a herpes vaccine. Using a completely different strategy than previous, failed herpes vaccines, the researchers behind this breakthrough targeted the part of the virus that allows it to hide from our immune systems. If this vaccine works as hoped, recipients will be able to mount an immune defense when exposed to the virus, blocking it from establishing a permanent home in nerve cells. It might even suppress outbreaks in people who already have herpes. Continue reading →