Wednesday 7 October 2015

What is the human papillomavirus (HPV) vaccine?


Definition

Two brands of the human papillomavirus (HPV) vaccine, Cervarix and Gardasil, have been approved by the US Food and Drug Administration. Both brands can prevent most cases of cervical cancer if the vaccine is given before exposure to HPV. Gardasil can also prevent genital warts in both females and males.




More than forty types of HPV can infect the genital areas of both males and females. Most HPV types cause no symptoms and resolve on their own. Some types of HPV, however, cause cervical cancer and other, less common, genital cancers (of the penis, anus, vagina, and vulva). The Centers for Disease Control and Prevention (CDC) estimate that 17,500 women and 9,300 men are affected by cancers caused by HPV each year. Some types of HPV can cause genital warts. Because the HPV vaccine does not prevent all kinds of cervical cancer, females who receive the HPV vaccine still need to have regular Pap tests.




Candidates for Vaccination

The HPV vaccine should be given before beginning sexual activity with another person. The vaccine is most effective in persons who have not been exposed to HPV.


The vaccine is recommended for children age eleven and twelve. However, the vaccines can be administered in children as young as nine years of age. Also, people through age twenty-six years can receive the vaccine if they did not receive any or all of the shots when they were younger.




Dosage

The HPV vaccine is given as a three-dose series. Each dose is 0.5 milliliters, administered intramuscularly, preferably in a deltoid muscle. It is best to use the same vaccine brand for all three doses. The minimum time between dose one and dose two of the vaccine is four weeks; between does two and dose three is twelve weeks. The minimum time between dose one and dose three is twenty-four weeks. Doses that were received after a shorter-than-recommended time interval should be given again.




Risks

Generally, the HPV vaccine is very safe, but mild to moderate reactions have been reported. Reactions include pain, redness, itching, bruising, or swelling at the injection site; mild to moderate fever; headache; nausea; vomiting; dizziness; and fainting. Persons who are allergic to the ingredients of the vaccines, including yeast, should not receive the vaccine, nor should pregnant persons.




Impact

The HPV vaccine is the first preventive cancer vaccine. Initially, the vaccine was controversial because some parents and religious groups claimed it would make casual sex more acceptable, especially among girls, although studies by both Merck (the manufacturer of Gardasil) and independent researchers show no link between receiving the vaccine and increased sexual activity. Lawmakers are debating whether to make this vaccine mandatory; as of December 2015 it was mandatory only in Rhode Island, Virginia, and Washington, DC, and many teenagers were still not receiving it. According to the CDC, in 2014 60 percent of adolescent girls and 42 percent of boys had received at least one dose of the vaccine, an increase over the previous year but still a lower percentage than those receiving other vaccines recommended for eleven- and twelve-year-olds, such as the Tdap (tetanus, diphtheria, and pertussis) and meningitis vaccines.




Bibliography


Boston Women’s Health Collective. Our Bodies, Ourselves: A New Edition for a New Era. 35th anniversary ed. New York: Simon, 2005. Print.



Centers for Disease Control and Prevention. “FDA Licensure of Bivalent Human Papillomavirus Vaccine (HPV2, Cervarix) for Use in Females: Recommendations of the Advisory Committee on Immunization Practices (ACIP).” Morbidity and Mortality Weekly Report 28 May 2010: 626–29. Print.



Centers for Disease Control and Prevention. “FDA Licensure of Quadrivalent Human Papillomavirus Vaccine (HPV4, Gardasil) for Use in Males: Recommendations of the Advisory Committee on Immunization Practices (ACIP).” Morbidity and Mortality Weekly Report 28 May 2010: 630–32.



Centers for Disease Control and Prevention. “HPV Vaccine Information for Young Women.” Centers for Disease Control and Prevention. Dept. of Health and Human Services, 26 Mar. 2015. Web. 30 Dec. 2015.



Daniel, Jennifer. “Good Talks Needed to Combat HPV Vaccine Myth.” New York Times. New York Times, 9 Nov. 2015. Web. 30 Dec. 2015.



Dunne, E. F., and L. E. Markowitz. “Genital Human Papillomavirus Infection.” Clinical Infectious Diseases 43 (2006): 624. Print.



“Human Papillomavirus (HPV) Vaccines.” National Cancer Institute. Natl. Inst. of Health, 19 Feb. 2015. Web. 30 Dec. 2015.



Larsen, Laura. Sexually Transmitted Diseases Sourcebook. Detroit: Omnigraphics, 2009. Print.



McCance, Dennis J., ed. Human Papilloma Viruses. New York: Elsevier Science, 2002. Print.



Plotkin, Stanley A., Walter A. Orenstein, and Paul A. Offit. Vaccines. 5th ed. Philadelphia: Saunders, 2008. Print.



“Quadrivalent Vaccine Against Human Papillomavirus to Prevent High-Grade Cervical Lesions.” New England Journal of Medicine 356 (2007): 1915–927. Print.



Thompson, Dennis. "CDC Says Too Few US Teens Getting HPV Vaccine." CBS News. CBS, 30 July 2015. Web. 30 Dec. 2015.



Trottier, H., and E. L. Franco. “The Epidemiology of Genital Human Papillomavirus Infection.” Vaccine 24 suppl. 1 (2006): S1–S15. Print.

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