Understanding Psychology (10th Ed)

 SEXUALLY TRANSMITTED INFECTIONS (STIs) 
Millions of people suffer the discomfort—not to mention the psychological distress—
of a
 sexually transmitted infection (STI), 
a disease acquired through sexual contact. 
Estimates suggest that one in fi ve people in the United States is infected with some 
form of STI, and at least one in four will probably contract a STI during their life-
times. The United States has the highest rate of sexually transmitted infections of all 
the economically developed countries in the world in part because people in the 
United States don’t talk about sex as frankly or receive as much sex education as 
people in other developed nations (see Figure 6; CDC, 2008).
These are the major STIs:
• Chlamydia. The most widespread STI is chlamydia, a disease that in women 
initially produces no symptoms and in men causes a burning sensation 
during urination and a discharge from the penis. If it is left untreated, 
chlamydia can lead to pelvic infl ammation, urethral damage, arthritis, and 
even sterility. There are almost 3 million new cases each year in the United 
States. Because it usually produces no symptoms in females, the Centers for 
Disease Control recommends that sexually active women under age 26 
should be tested for the disease every year. Once diagnosed, chlamydia can 
be cured with antibiotics, most often azithromycin or doxycycline (Ku et al., 
2002; CDC, 2004a).
• Genital herpes . Genital herpes is a virus related to the cold sores that sometimes 
appear around the mouth. Herpes fi rst appears as small blisters or sores 
around the genitals that later break open, causing severe pain. These sores heal 
after a few weeks, but the disease usually reappears typically four or fi ve 
times in the year following infection. Later outbreaks are less frequent, but the 
infection, which cannot be cured, often causes psychological distress for those 
who know they are infected. During the active phases of the disease, it can be 
transmitted to sexual partners. Genital herpes is common among college-age 
students: About 17% of 20- to 29-year-olds have the infection (Farrell, 2005).
• Trichomoniasis. Trichomoniasis is an infection in the vagina or penis. Caused by 
a parasite, it is often without symptoms, especially in men. Eventually, it can 
cause painful urination and intercourse, a discharge from the vagina, itching,