Human papillomavirus

From Wikihealth
Jump to: navigation, search

Human papillomavirus (HPV) is a class of more than 100 related viruses that cause warts, which are medically known as papillomas. These are non-cancerous tumor growths on the skin. As there are many types of papillomaviruses, the viral strains that cause common warts which grow on the extremities like hands and feet are different from those that cause growths in the oral cavity or the genitals. There are high risk HPVs that are said to cause cancer.

Contents

Description of the virus

There are about 60 subtypes of human papillomavirus identified. About one-third of these subtypes can be spread through sexual contact. Usually this virus thrives on the epithelial cells of the skin and mucosa. It requires direct contact in order to be infected with the virus.

These common human papillomavirus types, HPV types 6, 11, 16, and 18, are those that affect the anus and genitals although there are other strains that may cause warts in these areas. Of these, HPV-6 and HPV-11 are said to cause genital warts and mild cervical dysplasia which are low-risk. HPV strains 16, 18, 31, and 45 belong to the high risk group as they cause cancers in the anogenital region (anus and genitals) and in the cervix. HPV-5 and HPV-8 cause skin cancer in people with epidermodysplasia verruciformis, a rare skin condition. However, doctors consider HPV 16 and 18 to be the most deadly as they are transferred through sexual contact and cause 95% of cervical cancers.

Transmission

This virus is commonly transmitted through sexual contact, usually during vaginal and anal sex. It may also be transmitted through oral sex or direct genital contact. Very rarely, a pregnant woman may pass it on to her baby during vaginal delivery.

The infected person frequently does not realize that he/she is passing on the virus to his/her partner. It is also possible to harbor more than one strain of human papillomavirus.

Warts may manifest within weeks or months after contact with the infected person even if that person does not have any genital warts.

Prevention

Vaccines like Cevarix® and Gardasil® are developed to combat the most common types of human papillomavirus. The effectiveness of these vaccines is gained after three doses. Both brands can be used by females but only Gardasil® is given to males. It is recommended that females get vaccinated for HPV at age 11 - 26 while it is given much earlier in males at age 9 - 26.

Condoms may actually lower the risk of exposure to human papillomavirus but they should be used with every sex act, from start to finish, providing an effective barrier against it.

In addition, long-term monogamous sexual relationships lower the risk of being infected with human papillomavirus although abstinence from sexual contact of any kind is the surest way of preventing the virus from infecting the body.

Signs and symptoms

Most people who have contracted this virus do not develop any symptoms. More often than not, the body's natural resistance clears the virus within two years.

Genital warts caused by human papillomavirus show up as a small bump or a group of bumps in the genital area. They may be small or large, raised or flat, or clustered together. If left untreated, genital warts may disappear, remain unchanged or grow. They usually do not develop into cancer.

Infections of the human papillomavirus in the cervix do not show any symptoms but they are the most deadly when they cause cervical dysplasia. Women who have vaginal genital warts might experience bleeding after sexual intercourse or have an abnormal vaginal discharge.

Diagnosis

It is important for people who suspect they have genital warts to have a health professional see the affected area so that any other cause may be ruled out. Doctors diagnose genital warts in males mostly through direct visual examination.

Human papillomavirus infections in women are detected through HPV test, a form of general cervical cancer screening, which is given to women with ambiguous pap smear test results and for women over age 30. This test can identify thirteen (13) of the high-risk types of HPV that may cause cervical cancer and looks for viral DNA in cervical cells samples. In addition, medical professionals may conduct copolscopy and a biopsy to confirm their diagnosis.

At the moment, there are no approved tests to detect HPV infection in men.

Treatment

Visible genital warts can be removed manually or with medications.

Manual removal of large, clustered genital warts includes cryosurgery, loop electrosurgical excision procedure (LEEP), or conventional surgery. Chemicals like salicylic acid, trichloroacetic acid or podophyllin solution is usually given to smaller warts. After wart removal, the body's immune system gradually clears the virus but there is a chance of being re-infected again.

Imiquimod® cream has been recently approved by the US Food and Drug Administration. It works by stimulating the immune system to fight the virus.

Philippine scenario

According to the statistics in 1998, the median age of first sexual contact is from age 21 to 22. However, in a recent study in 2002, 12% of females and 18% of males have shown to be actively engaged in sex before they turn 18. This makes Filipinos vulnerable for human papillomavirus infections.

There is a call from certain groups to include HPV vaccinations as protocol in the routine immunization program implemented in the country. However, certain factors like the cost and the propensity towards promiscuity have deterred people from advocating the said vaccination. Other groups prefer more studies to be done before human papillomavirus become protocol vaccinations as the current vaccines available target only the most common strains like HPV-16 and HPV-18. Current research shows that HPV-45, 52 and 58 are prevalent in the country making such vaccinations useless.

Epidemiologists advocate that even those who have been vaccinated for human papillomavirus should still undergo screening, particularly in sexually active young women. Initial screening must be done three months after her sexual debut and every year after that. After three years of negative results, she can undergo screening every three years.

External links

References