Page 103 - 86 human physiology part-2

Chapter 16

Prevention of Sexually Transmitted Diseases

Although healthcare professionals suggest that safer sex, such as the use of condoms, as the most
reliable way of decreasing the risk of contracting sexually transmitted diseases during sexual activity,
safer sex should by no means be considered an absolute safeguard. Abstinence is the best control of and
protection from the transmission of sexually transmitted infections. The transfer of and exposure to
bodily fluids, such as blood transfusions and other blood products, sharing injection needles, needle-
stick injuries (when medical staff are inadvertently jabbed or pricked with needles during medical
procedures), sharing tattoo needles, and childbirth are all avenues of transmission. These means put
certain groups, such as doctors, haemophiliacs and drug users, particularly at risk.

Human Papillomavirus (HPV)

There are over 100 types of this virus which is often asymptomatic. Nearly 3 out of 4 Americans
between ages 15 and 49 have been infected. It can be contracted through one partner and remain
dormant allowing it to be transmitted to another. Some types can cause cervical cancer.

Genital HPV infection is a sexually transmitted disease that is caused by human papillomavirus.
Human papillomavirus is the name of a group of viruses that includes more than 100 different strains.
More than 30 of these are sexually transmitted and they can infect the genital area of men and women.
Approximately 20 million people are currently infected with HPV and at least 50% of sexually active
men and women will acquire HPV at some point in their lives. By age 50 at least 80% of women will
have acquired HPV and about 6.2 million Americans get a new HPV infection each year. Most people
who have HPV don't know that they are infected. The virus lives in the skin or mucous membranes and
usually causes no symptoms. Commonly some people get visible genital warts or have pre-cancerous
changes in the cervix, vulva, anus, or penis. Very rarely, HPV results in anal or genital cancers. Genital
warts usually appear soft, moist, pink, or flesh colored swellings. They can be raised, flat, single, or
multiple, small or large and sometimes cauliflower shaped. Warts may not appear for weeks or months
or not at all and the only way to diagnose them is by visible inspection. Most women are diagnosed
with HPV on the basis of abnormal pap tests and there are no tests available for men. There is no cure
for HPV. The surest way to eliminate risk for HPV is to refrain from any genital contact with another
individual. For those who choose to be sexually active, a long term monogamous relationship with an
uninfected partner is the strategy most likely to prevent future HPV infections.The next best way to
help reduce risk is using a condom but the effectiveness is unknown.

What is the connection between HPV and cervical cancer? All types of HPV cause mild pap
test abnormalities which do not have serious consequences. Approximately 10 of the 30 identified HPV
types can lead to development of cervical cancer. Research as shown that for most women, 90%
cervical HPV infection becomes undetectable within two years. Although only a small proportion of
women have persistent infection, persistent infection with the high risk types of HPV is the main risk
factor for cervical cancer.

A pap test can detect pre-cancerous and cancerous cells on the cervix. Regular pap testing and
careful medical follow up, with treatment if necessary, can help ensure that pre-cancerous changes in
the cervix caused by HPV infection do not develop into life threatening cervical cancer. The pap test
used in the U.S. cervical cancer screening programs is responsible for greatly reducing deaths from
cervical cancer.

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