HPV
Abstract
Human papillomavirus () is a pervasive human pathogen that causes cervical and other cancers as well as genital warts. Human papillomavirus infection is most common among young to median aged, sexually active individuals, and it is so prevalent that approximately 75% to 80% of sexually active individuals will become infected in their lifetime (Centers for Disease Control, 2011). In our paper, we are trying to establish a common ground of understanding as to the history behind this virus and the current findings of present day.
Human Papillomavirus (HPV): It?s More Common Than we Think
One of the first signs of Human Papilloma Virus (HPV) was in Italy in 1842 when a doctor noticed that married women and prostitutes developed cervical cancer, but nuns did not. While the doctor did not successfully determine the cause due means and lack of technology, this research was one of the first signs that cancers could be sexually transmitted (Herzog, 2011). The next significant development came in 1907 when Giuseppe Ciuffo determined that skin warts and genital warts were related and the likely cause of both types of warts was a virus. This hypothesis was confirmed in 1949 when technology became available to observe the virus itself. The overall study of papillomaviruses took a large step forward when Peyton Rous discovered that the viruses could cause skin cancer in rabbits (Herzog, 2011). By the 1970s, doctors had recognized that some kind of sexually transmitted disease was causing cervical cancer. Doctors had noticed that women with cervical cancer also tended to have genital herpes. Although this was a coincidence, doctors blamed herpes. German virologist Harald zur Hausen proposed in 1976 that HPV, was not herpes, HPV was the cause of cervical cancer, a theory that other scientists originally rejected. In 1983 and 1984, Harald zur Hausen discovered HPV DNA in cervical cancer tumors, proving his theory. In 2008, he received the Nobel Prize for this research (Herzog, 2011).
Today, the Human Papilloma Virus (HPV), consists of double stranded DNA and is typically transmitted sexually. More than 120 HPV subtypes have been identified, and so far there are other forms of HPV which are also sexually transmitted, and are a serious problem. These are; HPV-16, HPV-18, HPV-31, and HPV-45 (Erickson, 2010).Many HPV subtypes can readily infect the respiratory tract, resulting in respiratory papillomatosis (tumor growths in the respiratory track); oral mucosa, leading to cancerous and precancerous lesions; and the anal and perianal areas, resulting in Condylomata acuminata (genital warts) as well as cancer formation (Erickson, 2010). Current findings show that some strands of the virus can cause warts, while others remain latent in an individual for long periods of time without any noticeable differences in the vaginal or penile area but some of the latter can cause cervical changes that lead to cancer.
Cervical cancer is the second leading cause of cancer deaths in women worldwide (Curtis, 2004). The most dangerous of HPV?s are; 16 and 18, which are transmitted through sexual contact and are known to cause up to 95% of cervical cancers: currently HPV-16 and HPV-18 are also being linked to oral cancer (Curtis, 2004). As one can see on the graph our HPV range within the U.S. is relatively high amongst the rest of the world.
This leads this paper back to the beginning as to doctors back in the 1800?s who found cancers in promiscuous women versus women who did not engage in sexual relations, but it was not until the early 1980?s did a break through occur for science confirming HPV was a cancer causing issue amongst mostly women of a certain age. The history behind HPV is remarkable; respectively, barriers occurred during these centuries due to means, availability of research and technology. Currently, as a country we are trying to educate our men and women about this virus: modes of transmission, symptoms, and getting vaccinated.
In terms of how it can occur, for example; the oral cavity is an area of a moist epithelial surface (squamous cells) and other areas covered by skin and/or mucosa are the throat, tongue, tonsils, vagina, penis, and anus (Scully,2002). The parts of the oral cavity that are involved when the disease is transmitted are: the back third of the tongue, the back part of the roof of the mouth, the tonsils, and the side and back wall of the throat (Scully, 2002). The infection can be in the oral cavity without causing any changes within or can actually cause the growth of genital-like warts in the area infected. Though the growth of warts in the throat is rare, it is still considered a sign or symptom of oropharyngeal cancer. These warts are called, recurrent respiratory papillomatosis or RRP (Centers for Disease Control, 2011). Transmission of the virus occurs when these areas come into contact with the HPV virus, allowing it to transfer between epithelial cells. While it is becoming established, both conventional and oral sex, are means of transferring the HPV virus, it is still poorly understood what other transfer pathways may exist. A study done by Dr. No-Hee Park showed that the mouth was, at the cellular level, structurally very similar to the vagina and cervix (Scully, 2002). Both organs have the same type of epithelial cells that are the target of HPV 16 and HPV 18 (Curtis, 2004). The majority of oral cancers are cancers of epithelial cells, primarily squamous cell carcinomas, not unlike the cancers that affect the cervix. Dr. Park’s study also showed that smoking and drinking alcohol help promote HPV invasion (Scully, 2002). Combine tobacco and alcohol with HPV, and the epithelial cells in the mouth, and it is a possible recipe for the development of an oral cancer. The American Dental Association states that 60% of the U.S. population sees a dentist every year (Centers for Disease Control, 2011). Hygienists alone can do “opportunistic” cancer screenings of the existing patient population which a majority of existing patients visit a dental office every day, this would yield tens of thousands of opportunities to catch oral cancer in its early stages.
HPV is a very common virus. It is estimated that over twenty million Americans are infected with HPV, making it the most common sexually transmitted disease (Centers for Disease Control, 2011). In most cases sexual transmission of HPV is through vaginal or anal intercourse, transmitting HPV through oral sex is not uncommon in fact oral sex transmission is on the rise (Erickson, 2010). HPV also uses a mode of transmission through sexual skin-to-skin contact. HPV is difficult to prevent because no penetration is needed to transmit the virus. Studies show that condoms do provide some protection against HPV, but because parts of the genitalia remain exposed during condom use, there is still a risk of transmission (Centers for Disease Control, 2011). By touching someone or something infected by the virus and then touching one’s genital without washing one?s hands is another method of HPV transmission. Believe it or not, HPV transmission through kissing is a possibility: As per medical practitioners, theoretically, mouth to mouth kissing should not transmit the virus. However, a study has shown that ?The French Kiss? does spread the HPV. Probability of oral HPV infection increases with increase in the number oral sex or open-mouthed kissing partners (Erickson, 2010). The only guaranteed means of preventing HPV is through absolute abstinence from all sexual contact; however this is unrealistic for most adults.
The HPV virus lives in mucous membranes, symptoms can be visible; HPV symptoms in the mouth may look like a lump or growth. Sometimes they are shaped like cauliflower. Oral HPV can cause blisters to develop on the inside of the cheeks, roof of the mouth, tongue or the back of the throat (Curtis, 2004). Open lesions in the mouth can also cause liquid pus that may bleed if they are disturbed by a toothbrush or mouthwash. New warts may develop in and around the mouth and along the back of the throat as a result of oral HPV (Curtis, 2004). Inflammation, swelling and irritation of the lining of the mouth and throat are symptoms of oral HPV that can cause persistent pain. Cancer on the lips, tongue, cheek and palate are the symptoms of oral HPV infection that can cause facial defects and difficulties with speech and eating (Centers for Disease Control, 2011). In the genital area, there are some types of HPV that are high-risk, cancer-causing strains, other strains that are known to cause genital warts. The HPV strains responsible for causing genital warts do not cause cancer, and vice versa (Curtis, 2004). The strains of HPV that are known to cause cervical cancer do not produce any symptoms. These types of HPV are detected through a yearly pelvic exam along with a pap smear for women. Unfortunately, there is no medical test available for men.
There are two types of HPV vaccines, Gardasil and Cervarix; both vaccines will protect against HPV for at least five years, they both protect against HPV types 16 and 18, which cause 7 out of 10 cases of cervical cancer. Gardasil also protects against types 6 and 11and they help 9 out of 10 cases of genital warts (Curtis, 2004)). The vaccines make your body’s immune system produce antibodies to these HPV types. The antibodies protect you from getting infected with HPV. The HPV vaccines are given in a series of three shots (Curtis, 2004). It is recommended that all girls and women ages 9 to 26 get an HPV vaccine. Boys and men ages 9 to 26 can get the vaccine to prevent genital warts (Curtis, 2004). The HPV vaccine works best in people who have not yet had sex or been exposed to HPV: But even those who have had sex may benefit from the vaccine.
In summary, from the doctor in the 1800?s to German virologist Harald zur Hausen for devoting his life?s work to his theory proven to be correct in the early 80?s later creating a vaccine for young individual?s today is undoubtedly an amazing feet for our century. Today, we can make the choice for our loved ones to become vaccinated or abstain from sex but in reality HPV is like a dark plaque that can occur without a moment?s notice if the players involved are not being careful with their lives. Dr. Hausen intended that vaccine to help reduce cancerous numbers in the fight against this vicious virus. Our goal as a country is to educate our men and women of today, by getting vaccinated against HPV, limiting the amount of sexual partners one has in their lifetime, and using a condom each time one has sex are all excellent ways to reduce the risk of contracting HPV.
References
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