Humanbeings coexist with different types of pathogen that subject them toa constant risk of being infected with various diseases. Thesepathogens (including bacteria, parasites, fungi, and viruses) causediseases that are transmitted through different means and affecthuman life in dissimilar ways. Although many people think that HIV isthe most common type of sexually transmitted diseases, studies showthat human papillomavirus (HPV) is more common than other types ofinfection (Kang, Pang, Huang & Qiao, 2015). The high prevalenceof HPV compared to other types of infection is confirmed by the factthat almost 80 % of all people who are sexually active are affectedby the virus at least once in their lifetime (Kang etal.,2015). Although HPV us classified as one of the most common types ofviral infection that affect sexually active people, its symptoms maynot be as severe as those of other kinds of disease. This paper willprovide a discussion of HPV, with a focus on its causative agent,history, epidemiology, clinical manifestation, pathology, treatment,and socioeconomic as well as political issues associated with thedisease.
CausativeAgent of HPV
Theterm “human Papillomavirus” is derived from the name of thepathogen that causes HPV. Currently, it is estimated that there aremore than 150 types of HPV that have been discovered, but some ofthem do not cause health problems to human beings. It is only about40 of the HPV types that have the capacity to cause differentdiseases to male or female genital areas (Pandey & Mishra, 2012).Different types of the virus are distinguished from each other bybeing designated with numbers. This designation of numbers makes iteasy determine the impact that each of the viruses cause once theyinfect the patient. For example, it is easy to state that HPV-2, 7,and 22 cause warts while HPV-16, 18, 31, and 45 are responsible forthe occurrence of genital cancers (Boumba etal/,2013). Therefore, the type of infection considered in this paper iscaused by HPV, which is a DNA type of virus. The pathogen belongs tothe papillomavirus family.
HPVis a DNA virus that was discovered more than 60 years ago. In 1956, agroup of scientists suspected that cervical cancer could be caused bythe HPV virus (Pandey & Mishra, 2012). They gave the pathogen itscurrent name since it was mainly associated with the occurrence ofwarts referred to as papillomas. The group of scientists whodiscerned the virus tried to compare the lifestyle of the ladies whosuffered from cervical cancer to their healthy counterparts. Theyinitial observation indicated that women who had sex with more thanone partner and started romantic relationships at an early age wereat a higher risk of suffering from cervical cancer compared to thosewho avoided risky behaviors (Pandey & Mishra, 2012). Thisobservation motivated a German virologist known as Harold Hausen toconduct a lab experiment that could the specific type of pathogenthat was responsible for the occurrence of warts and cancer among thesexually active human beings.
Bythe time Hausen completed the experiment, HPV types 1-5 had beendiscerned. He discovered a new type that he called HPV-6 that had ahigh concentration in warts, but could not be seen in cervical cancerpatients (Pandey & Mishra, 2012). This frustration motivatedHausen to conduct more experiments that resulted in the discovery ofanother strain referred to as HPV-11 that is highly concentrated intumors that caused cervical cancer. A major breakthrough was made in1983 when HPV-11 was discovered three out of 24 cases of cervicalcancer (Pandey & Mishra, 2012). Other strains were discoveredbetween the 1980s and the 1990s. Dots were joined together in 1995 bythe International Biological Study on Cervical Cancer, which resultedin the discovery of the fact that HPV was responsible formore than93 % of all cased of genital cancer and warts (Pandey & Mishra,2012). Similar studies conducted in 1999 by the Cancer Research UKresulted in a conclusion that HPV causes about 99.7 % (close to 100%) of all cases of cervical cancer (Pandey & Mishra, 2012).Currently it has been proven beyond reasonable doubt that HPV is realand it is the most common type of sexually transmitted viralinfection in the world. In addition, the increase in the level oftechnology has allowed scientists to identify different strains ofHPV and the specific kinds of infection that they cause.
Theprocess of developing a vaccine for the human strains of HPV waseasier since scientists borrowed the methods that were applied byanimal researchers in the 1950s. By the end of the year 2008, aneffective vaccine had been developed and rolled out in severalcountries, such as the U.K. (Chan etal.,2015). However, members of the public had little knowledge about HPV.In addition, the fact that HPV infection was associated withirresponsible sexual behaviors resulted in the development of anegative attitude toward among the members of the public. Thediscovery of vaccines, coupled with the increase in civic educationhas resulted in the change of attitude towards this type of viralinfection (Chan etal.,2015). One of the recent studies indicated that civic education hasenabled about 63.0 % of the women enhance their awareness about HPVand its vaccination (Kang, Pang, Huang & Qiao, 2015). These womenhad a positive attitude towards HPV vaccine and they were willing tohave their daughters immunized against the virus. The data confirmthat many people have overcome the stigma that is associated with therelationship between HPV and risky sexual behaviors.
Researchershave reported different rates of HPV prevalence in various regions.According to Boumba etal.(2013) about 50-75 of all women in the world who are sexually activesuffer from HPV infection at a point in their life. However, somestrains of HPV are more common than others. For example, HPV-16 and18 are responsible for about 70 % of all lesions that affect thegenitals of the sexually active people (Boumba, Moulliff, Halali, L.Moukassa & Ennaji, 2013). The same study indicated that theprevalence rate among subjects with normal cervical cytology is1.4-25.6 %.
Thefact that most of the studies conducted in the past focus on theprevalence of HPV in women has resulted in the development of aperception that HPV is a pathogen that only affect ladies. However,one of the rare studies that address the risk of the occurrence ofHPV among men indicated that its prevalence rate is about 60 % amongthe sexually active subjects (Palefsky, 2011). Most of the peopleassociate HPV with women because of its role in the occurrence ofcervical cancer. In men, the virus causes serious infections in thepenile shaft, scrotum, and corona. About 20 % of the infected mensuffer from anal infection, in spite of the fact that they reportsthat they have never engaged in same sex relationships (Palefsky,2011).
Figure1: Prevalence of HPV in male
Otherstudies have indicated that HPV is more prevalent in developingcountries compared to developed nations. According to Boumba etal.(2013) about 528,000 new cases of HPV infections that lead to cancerare reported every, but 85 % of them are diagnosed in the developingcountries. A higher prevalence rate that was more than the globalaverage of 54 % was also reported in the Middle East countries,including Qatar (Bansal, Elmi, Skariah, Haddad, Raddad, Hamadi,2014).
Theprevalence rate of cervical cancer that has direct connected withstrains of HPV is about 31.8 % for women aged below 30 years (Boumbaetal/,2013). This percentage reduces to 11 % for women aged above 60years.Therefore, studies report different trends in the prevalence rate ofHPV infections and different types of cancer. The prevalence rate ofthe oral HPV 16 DNA is about 6.9 % for both men and women (Laskar &Swain, 2015). Similarly, the prevalence rate of head and neck cancersthat are attributed to HPV infection is about 4.5 % for individualsaged between 14 and 69 years. The average prevalence rate takesaccount of both genders.
Figure2: HPV prevalence by age
FromFigure 2, prevalence increase steadily to the age of about 34 years.It starts declining and then increases up to the age of 45-49.
Signsand Symptoms of HPV
Theimmune system that protects human beings from different pathogens hasthe capacity to fight most of the strains of HPV before they developserious symptoms. The HPV infection that developed to advanced stagesmanifests in the form of four types of wart. The first type of wartis referred to as genital warts and appears in the form of flatlesions or cauliflower-like bumps (Laskar & Swain, 2015). Thesewarts affect women near the vulva, cervix, or the anus. In men thewarts affect the penis, around the anus, and scrotum. Genital wartsare quite common, but they rarely cause pain or discomfort topatients.
Figure3: Prevalence of HPV anal infection
Thesecond type of wart that is seen in patients with HPV infection isreferred to as plantar warts. These warts are grainy and hard. Theytend to develop on the balls of the patient’s feet or on the heels(Boumba etal/,2013). Unlike the genital warts, plantar lump cause some discomfortto infected persons.
Thethird category of lumps that can be considered when diagnosing HPVinfection is known as flat warts. Flat warts are slightly raised fromthe skin. In addition, they have flat tops that distinguish them fromother types of lump. Unlike other types of lumps that develop onspecific parts of the body, flat warts can grow anywhere (Laskar &Swain, 2015). However, there tend to appear on the face in childrenand in the beard regions in men. In addition, they appear on the legsin women in most of the cases. These types of genitals appear inpatients depending on the strain of HPV that has infected them.
Apartfrom the wide range of warts that are considered the symptoms of HPVinfection, patients may show different signs when the diseases leadto the development of cancer. Patients do not show any symptom duringthe early stages of the infection. However, the signs start appearingthen the infection is left untreated for long, where the cancer cellspenetrate through the layer of the cervical tissue (Kang etal.,2015). Although symptoms that appear during this stage are associatedwith the cancer, they originate from the HPV infection. The first andthe most common type of symptom is irregular discharge that occursafter sex or between the menstrual periods. In some women, thebleeding may occur in the form of blood-streaked vaginal dischargethat is mostly dismissed as a type of spotting. The second type ofsymptom associated the cervical cancer that results from HPVinfection is unusual vaginal discharge. This discharge may be clear,white, brown, tinged with blood, watery, and foul smelling.
HPVaffects sexual organs, but there are some strains that infect otherparts of the body, including the palms and feet. The damage that theHPV cells cause on the body manifests through the development ofwarts and cervical cells that have uncontrolled growth. HPV is a DNAtype of pathogen. This implies that it causes damage to the targetcells by interfering with their genetic composition and structure.HPV integrates its DNA into the cell’s genome, but it does notstart reproducing immediately. Instead, HPV starts producing proteinsthat are required to facilitate the synthesis of more DNA (Molina,Valencia, Lamoyi, Paredes & Lizano, 2013). The proteins that areproduced by HPV commandeer the process of DNA synthesis. Viral genes(including E6 and 7) serve as oncogenes. Proteins encoded by viralgenes bind those that act as tumor suppressors, thus creatingconditions for cells to grow and divide uncontrollably. Therefore,HPV cause damage by introducing viral genes into the target cells.
Theincubation from the time of infection and the development of warts isestimated to be between two weeks to eight months. The infectioncycle of the virus is determined by the differentiation rate programof the host cells (Molina etal.,2013). The differentiation phase of viral growth accompanies thematuration of keratinocyte. The virus that infects the basalkeratinocytes as it targets the stem cells. At this level, the viralcells express high levels of proteins on the upper layers of squamousepithelium. It takes about 3 weeks from the time of infection to therelease of the virus. In most cases, HPV is not accompanied byinflammation, which implies that, the immune system of the hostremains ignorant of the virus. This results in the development ofchronic illnesses. Therefore, HPV cause infection in a sequalae, byduration from one phase to another varies from one strain to another.
Thehuman body responds to HPV infection through adaptive and innateimmunity. Regression of genital warts is facilitated by theinfiltration of the T-cells and macrophages. Infiltrating lymphocytestend to express different activation markers. The cytokine mulieu isthen dominated by pro-inflammatory cytokines. The cytokines cause theup-regulation of adhesion molecules needed for the process oftrafficking lymphocytes to the epithelium of capillaries found on thewarts (Molina etal.,2013). This process results in the downsizing of the lumps that formwarts. However, studies have shown that HPV cells are able to evadethe immune system through a wide range of mechanisms, which resultsin further development of the disease.
HPVsimilar to most of the infections does not have a cure. The infectioncures itself with time. However, there is a wide range of therapiesthat are recommended for proper management of HPV symptoms. The firstcategory of therapy is medication and it involves the administrationof pharmaceutical products. Medications are prescribed with theobjective of eliminating warts, but most patients try more than onetype of drug before the treatment can succeed. Salicylic acid refersto an over-the-counter type of drug that is works by removing thelayers of warts (Molina etal.,2013). However, it has some side effects, including the skinirritation.
Imiquimodis a type of cream that is applied on warts. This cream works byenhancing the immune system of the infected person. An increase inthe level of immune system enhances the ability of the body to fightthe HPV through the cell-mediated immunity (Molina etal.,2013). Some of the common side effects of the cream include swellingand redness at the sites where it has been applied.
Podofiloxis a type of cream that is prescribed in order to destroy tissuesthat form warts. It is also a topical medication, and its sideeffects include itching and pain at the sites of application(Kollipara, Ekhlasso, Downing, Lee, Guidy & Tyring, 2015).
Trichloroaceticacid is a strong chemical that is applied on the warts in order toburn them off. It is mainly applied on genitals and palms. It resultsin local irritation. These types of medication complement the immunesystem by reducing some symptoms. They limit the progression of theHPV infection. However, they fail to contain the development of HPVin some patients, which creates the need for surgery to be carriedout. Some of the common types of surgical operations and proceduresthat might be used to remove warts when medication fails includelaser surgery, electrocautery, and cryotherapy (Kollipara etal.,2015). These procedures halt the progression of HPV infection throughthe mechanical removal of warts.
HPVis sexually transmitted and it can be prevented through manystrategies. Currently, a vaccine for HPV is available and it can beused to protect individuals who are sexually active from warts. Thevaccine is known as gardasil and it also protects people from HPVVstrains that are associated with the development of cervical cancer(Kollipara etal.,2015). There is also another type of vaccine known as cervarix thatprotect sexually active people against the HPV strains that lead tothe development of cervical cancer. These are more effective whenadministered to kids before they become sexually active.Alternatively, sexually active people can use condoms, abstain, orreduce the number of partners. A combination of these measuresreduces the risk of contracting the virus from partners who arealready infected.
Socioeconomicand Political Issues
Thelack of adequate resources to finance programs that are designed tohelp people access is among the key economic challenges that thatfrustrated the efforts made to reduce the prevalence of HPV. There isa general perception that the issue of the lack of adequate resourcesfor health-related programs affects the developing and themiddle-income nations. However, studies have shown that thestakeholders who are mandated to fight the HPV infection in allcountries (including the developed nations) face some commonchallenges, such as the lack of substantial government endorsement,sustainable financing for the administration of vaccine, clearguidelines, and support in addressing the negative public perceptionabout the level of safety of various prevention measures (Latu &Homer, 2016). The lack of adequate financial support limits thenumber of people that the stakeholders in the health care sectorreach in the immunization and civic education campaigns. Thesefactors limit the capacity of players in the health care system tolimit the spread of HPV infection.
Inaddition, there are several social factors that have limited theeffectiveness of prevention measures for HPV infection. For example,poverty is a critical factor that denies millions of people thecapacity to access the health care facilities since they cannotafford insurance coverage and out-of-pocket fee (Cesario, 2015). Inaddition, the negative perceptions held by the society where peopleassociate HPV with irresponsible sexual behaviors discourage thevulnerable people from seeking the medical care and advice. Accordingto Cesario (2015) some people feel embarrassed anxiety, anduncomfortable when being screened for HPV. Therefore, stigma is asocial factor that reduces the effectiveness of prevention measures.In addition, an exposure to crime gives the HPV an opportunity tothrive. Rape is an example of crimes that can increase theprobability of being infected with HPV. This is quite common inovercrowded urban areas.
Thelack of effective policies that can help the vulnerable people reducethe risk of suffering from HPV has contributed towards the increasein the prevalence of viral infection. Governments in many countrieshave been able to make other types of vaccines universal and free inorder to help all people access them (Bailey, Chuang, Dupont, Eng,Foxhall, Merrill & Blanke, 2014). However, the lack of politicalwill to develop policies that will make the HPV vaccine universal andfree for all people has limited the capacity of many jurisdictions toreduce the rate at which the infections spreads each year.
Thereare two policies and practices that can be used to limit the spreadof HPV. First, an increase in the level of collaboration betweenlegislators and health care providers will lead to the development ofeffective policies that can enhance the findings. For example, thehealth care providers will be able to convince the legislators aboutthe significance of developing a policy that will make HPV vaccinefree for all people. This policy will allow all people to accesshealth care service, irrespective of their financial background (Latu& Homer, 2016). The successful implementation of a policy leadingto the delivery of HPV vaccine free of charge will require politicalgoodwill, financial resources, and collaboration among thestakeholders. Secondly, civic education is an effective program thatcan go a long way in addressing the stigma associated with HPVinfection. Effective civic education will help people understand theimportance of being screened regularly in order to ensure that theHPV infection is detected at an early stage. This practice will alsoreduce the risk of HPV developing to severe conditions, such ascervical cancer. Some of the factors that are needed in order toensure a successful implementation of the civic education policyinclude finances and volunteers.
HPVis currently one of the most common types of infections that aresexually transmitted. The fact that it is more prevalent than othertypes of infection is confirmed by the data showing that over 80 % ofthe people who are sexually active are likely to contract theinfection during their lifetime. The existence of more than 150strains of HPV makes the study of the virus quite challenging. Thesestrains cause varying types of infection. The identification ofdifferent strains and the types of infection that they cause was amajor breakthrough that enhanced the human understanding of theinfection. The study of the relationship between HPV and theoccurrence of different types of cancer started in the 1960s, butsignificant breakthroughs were made in the 1980s and the 1990s. Thelong time that it took before researchers could identify thisrelationship can be attributed to the existence of multiple types ofstrain that cause dissimilar signs and symptoms. The integration ofgenetic material into the host cells is the key mechanism throughwhich exerts its effects. Although this infection has no cure, thereare effective medications that address its key symptoms.
Bailey,H., Chuang, .T. Dupont, C., Eng, C., Foxhall, E., Merrill, K. &Blanke, D. (2014). American society of Clinical oncology statement:HPV vaccination for cancer prevention. Journalof Clinical Oncology,67, 1803-1815.
Bansal,D., Elmi, A., Skariah, S., Haddad, P., Raddad, A., Hamadi, A. (2014).Molecular epidemiology and genotype distribution of humanpapillomavirus among Arab women in the state of Qatar. Journalof Translational Medicine,12, 300-320.
Boumba,L., Moulliff, M., Halali, L. Moukassa, H. & Ennaji, M. (2013).InternationalJournal of Science and Research,6 (14), 521-255.
Cesario,K. (2015). HPV vaccine: Public health, politics, and personal choice.International Journalof Women’s Health and Reproductive Sciences,3, 123-125.
Chan,A., Brown, B., Sepulveda, E. & Clayton, L. (2015). Evaluation offotonovela to increase human papillomavirus vaccine knowledge,attitudes, and intentions in low-income Hispanic community. BMCMedical Research,8, 615-620.
Kang,G., Pang, L., Huang, R. & Qiao, Y. (2015). Effect of a groupeducational intervention on rural Chinese women’s knowledge andattitudes about human papillomavirus and HPV vaccine. BMCCancer,15, 691-683.
Kollipara,R., Ekhlasso, E., Downing, C., Lee, M. Guidy, J. & Tyring, K.(2015). Advancement in pharmacotherapy for noncancerous manifestationof HPV. Journalof Clinical Medicine,4, 832-846.
Laskar,S. & Swain, M. (2015). HPV positive oropharyngeal cancer andtreatment de-intensification: How pertinent is it? Journalof Cancer Research and Therapeutics,11 (1), 6-9.
Latu,R. & Homer, S. (2016). Cancer control in resource-limitedsettings. PacificJournal of Reproductive Health,1 (3), 99-101.
Molina,A., Valencia, F., Lamoyi, E., Paredes, A. & Lizano, M. (2013).Role of innate immunity against human papillomavirus infections andeffect of adjuvants in promoting specific immune responses. Viruses,5 (11), 2624-2642.
Pandey,M., & Mishra, M. (2012). Human papillomavirus screening in NorthIndian women. Asian Pacific Journal of Cancer Prevention, 13,2643-26-46.
Palefsky,M. (2011). Human papillomavirus-related disease in men: Not justwomen’s issue. Journalof Adolescent health,46 (4), 12-19.