Human Papilloma Virus (HPV) is one of the most widespread sexually transmitted infections in the world. More than one hundred types of HPV have been described since 1930s when the infection was identified.
HPV can lead to such serious diseases as “cervical intraepithelial neoplasia (CIN), cervical and other anogenital cancers (vulva, vaginal, anus, penile), head and neck cancers, genital warts, and recurrent respiratory papillomatoses” (Brisson et al. 5399). More so, according to World Health Organization (WHO) some types of HPV are found in about 70% of cervical cancer samples worldwide (Human Papillomavirus Laboratory Manual 5).
Fortunately, Papanicolaou (Pap) smear screening programs have led to reduction of cervical cancer mortalities (Shors 263). One more effective way to prevent the development of cervical cancer was introduced in the early 1990s (Shors 265).
Vaccination has been regarded as one of the most effective tools to prevent cervical cancer. However, some researchers cast doubt on the cost-effectiveness of vaccination. For instance, many researchers point out that vaccination is more beneficial for vaccine producers rather than for those vaccinated (Lippman 570).
Admittedly, high prize of vaccines, the lack of the necessary research in the field and existence of other effective tools of prevention raise many questions concerning the need in vaccination or its effectiveness. The present paper touches upon biology of HPV infection and its natural history. It also deals with the effectiveness of the vaccination pointing out the most effective tools of the cervical cancer prevention.
The history of the virus dates back 1932 when Richard Shope identified the first papilloma virus demonstrating the “the induction of papilloma in cottontail rabbits by a viral agent” (Ou & Yen 7). Nowadays more than 110 papilloma viruses are described. Though, this virus affects mammals as well as birds, papilloma viruses affecting humans are mostly studied (Shors 263).
HPV infection often causes occurrence of papillomas in the skin (these papillomas occur in genitals, hands or feet). The virus gets to the organism through the damaged skin (Shors 263). HPV is a non-enveloped virus measuring 55nm in diameter. It only affects “the cutaneous and mucosal epithelia of the anogenital tract or upper respiratory tract” (Ou & Yen 263). HPV cannot affect other skin layers (e.g. dermis) because “those cells are not metabolically active” (Shors 263).
The virus particles have dsDNA which are about eight thousand base pairs. It is worth mentioning that the receptor of the virus is still unidentified, though it is believed that heparin sulfate is the mediator of the virus’ entry (Ou & Yen 8). Research of HPV infections has led to the development of a particular classification.
There are three major types of HPV infections: high-, intermediate- and low-risk types (Shors 263). Types 18 and 16 often lead to the development of cancer. These types of the infection often lead to lethal outcomes. There can be a four or twenty year latent period. Therefore, diagnosing can be complicated in many cases.
Notably, these types of HPV infections were detected in cervical carcinoma samples in 1980s. Low-risk types of HPV (types 11 and 6) do not cause the development of cancer. The intermediate-risk types (31, 33, 51, 52, 83) do not usually lead to the development of cancer.
Reportedly, HPV infection is the most widespread genital infection in the United States of America. According to WHO about 440 million people worldwide are infected (Dizon et al. 2). Dizon et al. also point out that younger women are especially vulnerable, noting that the infection is often acquired within the first months of the “first sexual intercourse” (2). However, the virus is also common for men as well as for women.
As far as the transmission of the infection is concerned HPV is transmitted by such types of sexual intercourse as vaginal, anal, oral. Importantly, the use of condoms cannot guarantee complete protection against the transmission. Notably, the cases of vertical transmission of the virus (i.e. the transmission from mother to child) are very rare (Dizon et al. 4).
It is worth mentioning that HPV can be cleared by the immune system. However, researchers estimate this process differently. For example, Dizon et al. point out that only antibodies are found in 50% of women (4). Whereas, Haug notes that “almost all HPV infections” are cleared by the immune system (795).
As has been stated above the major concern of the researchers, officials and ordinary people is the association of HPV with cervical cancer. Screening is believed to be a very effective tool of the disease prevention as it enables to detect the infection and start the necessary treatment. However, two decades ago it was suggested that vaccination is the most effective tool to prevent HPV. Thus, the statement of WTO reveals this trend:
WHO recognizes the importance of cervical cancer and other HPV-related diseases as global public-health problems and recommends that routine HPV vaccination should be included in national immunization programmes, provided that: prevention of cervical cancer or other HPV-related diseases, or both, constitutes a public-health priority; vaccine introduction is programmatically feasible; sustainable financing can be secured, and the cost effectiveness of vaccination strategies in the country or region is considered. (Human Papillomavirus Laboratory Manual 7)
The first attempts to create a vaccine against HPV were undertaken in the early 1990s. It is necessary to note that the target types of the infection were types 16 and 18, those which cause cervical cancer. Reportedly, Diane Harper and her colleagues implemented a profound research which resulted in the creation of one of the first vaccines (Shors 267.)
This vaccine was reported to be “100% effective against persistent HPV-16/18 infections” (Shors 267). The vaccine was safe for women and it was effective for cervical cancer prevention.
The creation of this successful vaccine has led to the further development in the field. It also raised such questions as the need in male vaccination. It has been believed that both women and men should be vaccinated as men act as “vectors” for HPV. Interestingly, research implemented by Al V. Taira proved that vaccination was cost-effective for women, but it was not cost-effective in men (Shors 267).
There are many studies that explore the cost-effectiveness of vaccination in different countries. Thus, Brisson et al. consider the potential effectiveness of HPV vaccines in Canada suggesting that vaccines are potentially effective though the further research is necessary (5406). There are too many issues yet to be explored as it is still unclear whether routine vaccination can be regarded as fully cost-effective.
The researchers point out that policy makers should take into consideration a lot of factors before assigning this or that vaccine to routine vaccination:
… quantifying the duration of vaccine protection, estimating the QALYs-lost and costs related to genital warts to better understand the relative cost-effectiveness of the HPV-16/18 and HPV-6/11/16/18 vaccines, and using dynamic models to examine the efficiencies and cost-efficiencies of different screening and vaccine strategies in reducing HPV-related disease. (Brisson et al. 5406)
Another research implemented by Giuliano et al. focuses on the incidence and clearance of HPV in men (932). The researchers also state that vaccination is an effective tool of prevention, though it is important to develop the vaccines carefully taking into account many factors (Giuliano et al. 939).
Admittedly, researchers are still trying to evaluate the effectiveness of existing vaccines. The vaccine which draws much attention is HPV vaccine Gardasil which was manufactured by Merck. The vaccine was licensed by the Food and Drug Administration (FDA) in 2006. The vaccine was also approved in many other developed countries.
For instance, in Canada Gardasil was approved by the federal National Advisory Committee on Immunizations in 2006 as well (NACI). This vaccine is recommended for girls aged 9-12. The major goal of Gardasil is to reduce the number of cervical cancer cases (Shors 268).
However, the vaccine has faced a lot of criticism. Thus, Lippman argues that the decision to use the vaccine was made too hastily (570). It is pointed out that $300 million dollars allocated to launch vaccination program using Gardasil to “immunize young girls” is regarded as a highly disputable measure (Lippman 570).
Rapidly approved vaccination program raised questions concerning public policy. Lippman states that the vaccine and such prevention campaign is rather financially beneficial for certain people (570-571). It is also pointed out that the harmfulness of HPV is also overestimated. Such statements have the right to exist.
For instance, Haug states that the rate of cervical cancer cases is not that high as in the majority of cases the cancer was caused by HPV infections which persisted (795). Besides, it is still unclear whether HPV is the major factor which causes the development of cervical cancer. Apart from this, it is still not clear whether the vaccine has a long-term effect. More so, the effects of the vaccine are still underexplored. The vaccine itself can be harmful in particular cases, there were some publications considering such cases (Haug 795).
Admittedly, as long as such issues are discussed vaccination cannot be regarded as the most effective tool of cervical cancer prevention. Moreover, there can be no routine vaccination if it is still unclear whether the vaccine is effective or harmful. It is important to remember that the HPV vaccines’ long-term effects are still unknown as they were introduced quite recently.
Fortunately, there are two other effective ways to cope with the spread of HPV infections and the cervical cancer prevention. The first one to be mentioned is screening. There was a 70% reduction of cervical cancer mortalities during 1947 and 1984 due to Pap smear screening programs (Shors 263). Thus, early detection of HPV infections is a very effective tool to prevent the development of cervical cancer. Therefore, it is important to continue the program which is proved to be effective during several decades.
Thus, instead of vaccinating girls it is safer and more cost-effective to detect HPV infections occurrence. If to take into account that in the vast majority of HPV cases the immune system is capable of clearing the infection, it is possible to state that when the infection is detected it is easy to prevent more serious health problems. It is worth mentioning that screening was proved to be effective in developed countries. Therefore, such kind of programs can be also effective in developing countries.
More so, it is possible to state that screening as a program of cervical cancer prevention will be the most cost-effective measure in developing counties. Thus, HPV vaccines are unaffordable in developing countries due to the high cost of the vaccines. It is important to remember that cervical cancer is one of the major causes of death among females in developing countries and it is “the second most common cancer among women” in the world (Shors 263).
It goes without saying that screening programs are less costly but more effective than vaccination. Therefore, policy makers of all countries (be it a developed or developing country) should pay more attention to the development of such programs rather than allocating significant funds to support doubtful routine vaccination campaigns.
Admittedly, another effective measure to undertake is the proper education. Teenagers as well as their parents should be educated in terms of serious health problems associated with HPV infections. Many researchers mention the importance of providing the necessary information to people (Dizon et al. 2). Secondary education should play an important role in this process.
However, it is not enough to tell about the consequences of the infection. It can be helpful to launch campaigns promulgating ‘sexual responsibility’. Teenagers should understand the responsibility associated with the beginning of their sexual life. Apart from this it can be effective to launch similar campaigns in media.
At present sexual life is regarded as a way to prove the person is ‘adult’ enough. It is important to change the attitude towards sexual life in media to make teenagers see that it is not only about having fun, but it is about responsibility and building healthy (in all respects) relationships.
On balance, it is possible to point out that HPV infections have been researched for several decades. HPV is a common genital infection in many countries worldwide. It is usually associated with the development of many oncologic diseases. The development of cervical cancer which is characterized by high mortality is also said to be caused by HPV infections.
There are three major tools of cervical cancer prevention: vaccination, screening and educating. HPV vaccination which is reported to be cost-effective is highly disputable at present. Many researchers point out that vaccination needs further research as its long-term effects are still unknown. Moreover, vaccine’s high prices raise many questions. Screening has been an effective tool of HPV detection and, as a result, cervical cancer prevention.
This is the most effective measures to undertake in developed and developing countries as they are less costly and there can be no negative effects. However, this measure should be also supported by a large-scale campaign in media. Teenagers and their parents should be educated. They should be aware of the HPV infections’ causes and effects. What is more, it is also important to change young people’s attitude towards sexual life. They should learn to be responsible: to care about themselves and to care about other people’s health.
Works Cited
Brisson, Marc, et al. “The Potential Cost-Effectiveness of Prophylactic Human Papillomavirus Vaccines in Canada.” Vaccine 25.29 (2007): 5399-5408.
Dizon, Don S., Ashley R. Stuckey and Michael L. Krychman. Dx/Rx: Human Papilloma Virus. Sudbury, MA: Jones & Bartlett Publishers, 2010.
Giuliano, Anna R., et al. “Incidence and Clearance of Genital Human Papillomavirus Infection in Men (HIM): A Cohort Study.” The Lancet 377.9769 (2011): 932-940.
Haug, Charlotte. “The Risks and Benefits of HPV Vaccination.” The Journal of the American Medical Association 302.7 (2009): 795-796.
“Human Papillomavirus Laboratory Manual.” 2010. World Health Organization. Web.
Lippman, Abby. “Human Papillomavirus (HPV) Vaccination and the Development of Public Policies.” Journal of Epidemiology & Community Health 62.7 (2008): 570-571.
Ou, Jing-Hsuing James and T. S. Benedict Yen. Human Oncogenic Viruses. Hackensack, NJ: World Scientific, 2010.
Shors, Teri. Understanding Viruses. Sudbury, MA: Jones & Bartlett Learning, 2009.