The Facts About HPV: What it Is, What it Does, and Why You Probably Have It
We all remember middle school and high school health classes. For some, the teacher was the really awkward football coach, for others it was the pretty 24 year old woman who was new that year. Still more took it as just another class to sleep through as practice for sleeping in college lecture halls, and the teacher is a blur. In any case, all of them had one thing in common: a fascination bordering on the obsessive with sexually transmitted infections (STIs). We can vaguely remember the cheesy videos, the textbooks with the colored definition boxes, and the glossy charts. But beyond this fuzzy memory, most people don’t really remember much at all, and certainly do not remember much about an STI with a rather boring name like HPV. And that’s a shame, because according to Planned Parenthood, the highest rates of genital Human Papillomavirus (HPV) infection are found in adults between the ages of 18 and 28, and in fact, genital HPV is the most common sexually transmitted disease in the United States, surpassing even genital herpes.
However, that’s probably not a very surprising statistic nowadays. College students love to drink, party, and hook up, which means that passing around STIs is pretty common. But if you’re ready to have your happy little world jostled a bit, listen to this: “It is estimated that 75 percent of reproductive age women and men have been infected with genital HPV at some point in their lives,” says the Planned Parenthood website. And this is the STI that causes genital warts, and cervical, anal, and penile cancers.
The Facts
According to Dr. Robert Rose, an infectious disease virologist from the University of Rochester (U of R), HPV is actually the name for a family of related viruses that infect humans. There are over 100 different known strains, and it is estimated that there are up to 200 different types. The different strains infect different parts of the body, and cause lesions on the skin, sometimes in the form of genital warts.
Some strains of HPV only cause garden-variety warts on regular skin, and most of the time, people will get a “harmless” variety of HPV, their immune system will fight the virus, and it will pass through their system and be no more serious than a cold. However, roughly 30 of the known strains affect the genital region, and these are the more dangerous types.
HPV is caused by direct skin contact, most usually during sexual intercourse. And all types are fair game; oral, vaginal or anal sex with an infected partner can transmit the disease, even if no symptoms are visible at the time. However, the good news is that most people that get HPV get infected and get over it, says Dr. Rose. “It’s been called ‘the common cold of the genital tract,’” he says. He explains that the reason we can get multiple colds is because there are many different strains of the cold virus. It is the same with HPV, which means that a person could contract multiple strains of HPV in their lifetime, and even at the same time.
The bad news, on the other hand, is that the normal modes of protection are not as fail-safe as you might think. As Dr. Rose puts it, “Condoms are man-made objects, and therefore have some level of porosity. If [the condom] gets stretched, then it would be easy for something like HPV to slip through.” The National Institute of Health agrees, saying that though they do reduce the risk of developing HPV, studies have not confirmed that they prevent it. The only real way to be sure you don’t contract HPV is to not have sex.
So what should you do if you can’t agree to stop having sex? Well, if you’re a woman, the most important thing is to get an annual pap exam. According to Dr. Rose, men are usually just carriers of the strains that cause cervical cancer, so you can be having sex with a man with no symptoms who could easily pass on a type of HPV that could cause cancer in a woman. However, both men and women can equally contract the strains of HPV that cause genital warts. So, if you see any lesions, head straight to the doctor for diagnosis and treatment.
The Treatment
There are several different types of treatments available for the genital wart-causing HPV strains. Creams, such as Imiquimod, can be applied at home. Cryosurgery (freezing of the warts) can be done at the doctor’s office. Electrocautery (burning of the warts) is also sometimes used by doctors, but not as frequently as freezing. Cryosurgery is also the way that doctors will treat the cervical cancer-causing HPV strains. If a woman’s pap smear comes back abnormal (the cells are distorted), then the doctor will call the woman back to get a biopsy (a small snip and scraping of skin from the cervix) to observe under the microscope. Depending on the size and depth of the distorted cells, most often the doctor will then perform a freezing of the surface of the cervix to kill and slough off the distorted cells.
However, none of these methods are fool-proof, and genital warts and distorted pap smears may recur after treatment. For those having cryosurgery to remove warts for example, there is recurrence in about half, according to Dr. Rose. As for a recurrent distorted pap smear, the doctor can continue to perform cryosurgery as many times as necessary to remove the distorted cells, and if the woman has annual pap exams, it will almost always be in plenty of time to treat.
Prevention for the World
Dr. Rose has been in the immunology department at the U of R for 20 years. In that time, he has focused specifically on HPV, and finding a vaccine to prevent it. Today, his work has paid off. The first step in any vaccine testing is to determine the safety of the vaccine. The second step determines the dosage. Now, he and the team of researchers he works with are in the midst of the third and final step of vaccine testing for the HPV vaccine, which is to follow a large population of vaccinated individuals for several years. Right now, upwards of 50,000 women are participating in the last stage of the vaccine trial, and by 2007 or 2008 at the latest, the results will be in. In small clinical trials before this major trial, the drug was “proven to be 100 percent effective in preventing persistent infection,” said Dr. Rose, “which is simply unheard of in vaccine testing.”
The plan in the U.S. is to make this vaccine part of the normal vaccination cycle for young girls. The idea is that when a girl turns 12 (before sexual activity), she would simply go to the doctor and get a quick shot, and then be protected against HPV when she does begin sexual activity.
Unfortunately, the countries that are most affected by HPV may not have access to this vaccine unless Dr. Rose’s other plan also works out. India has the highest percentage of cases of cervical cancer caused by HPV in the world (roughly 240,000 out of 500,000 world wide cases). However, it is also a very poor country, and cannot afford to provide sterile vaccinations to all young girls, or pap smears for adult women.
For example, the U.S. alone pays over six billion dollars annually for pap exams for its women. And in addition to poverty, culture plays a role. Many Indian women do not want a man, even a doctor, examining them, which leads to many of them avoiding pap smears altogether, and basically signing their own death warrants.
But there is hope. Dr. Rose is now working to create transgenic plants. Simply put, he is trying to get the HPV vaccine to grow in potatoes, tomatoes and bananas, so that instead of requiring doctors and sterile needles, all that would be needed for an HPV vaccination would be to mix a freeze-dried tomato into some water, and drink a glass of tomato juice. Simply put, the fruits would be vehicles for the vaccine; eating the fruit would do the work of the needle. So far, he and the team have created both a transgenic potato and a transgenic tomato, and when the plants were fed to mice, the vaccine worked.
Although Dr. Rose states that the highest rates of acquisition of HPV is in the first year of college, and at any given time, anywhere from 25 to 40 percent of college-aged people are currently infected with HPV, there is not a lot of cause to worry. If women get annual pap exams, cancer can almost always be avoided. Out of the 5,000 deaths per year caused by cervical cancer in the U.S., it occurred almost exclusively in women who haven’t ever had a pap smear, or haven’t had one in five years or more. So though the poking and prodding may pinch a bit, it’s worth the peace of mind. And who knows: maybe one day we’ll go to the doctor and peel a banana instead of getting poked with a needle.
