December, 1997

Adolescents and young adults have a disproportionate number of sexually transmitted diseases (STDs) compared to adults. STDs can result in serious health consequences, both for young people and their children. Because women often show no symptoms for the most common STDs, chlamydia and gonorrhea, they are diagnosed and treated less frequently than men, who generally have symptoms. Adolescents face special obstacles in obtaining diagnosis and treatment even when they do show symptoms. They are reluctant to seek care, and/or providers are often hesitant to treat them. ¹² Because STDs increase an individual’s susceptibility to human immunodeficiency virus (HIV) infection, it is extremely important for these diseases to be treated.^{7, 10} Also, STD’s can cause tubal infection and thus infertility.

Young people are vulnerable to sexually transmitted diseases for both biological and behavioral reasons. In fact, worldwide, the highest reported rates of STDs are found among young people aged 15-19 and 20-24. In the developed world, two-thirds of all reported STD infections occur among men and women under the age of 25. In developing countries the proportion is even higher.⁶ Here are some prevalence data for specific diseases:

• Adolescents represent a large proportion of overall chlamydia infections worldwide—at least one-third. In Haiti and Nigeria, this age-group is reported to have the highest level of culture-detectable chlamydia.^{3, 4, 6} Prevalence levels can be as high as one-half of all sexually active young women.⁶

• Rates of gonorrhea are often highest among adolescents.⁸ As is true of other curable STDs, South Asia and sub-Saharan Africa have a disproportionate number of these infections, and adolescents comprise about one-third of all cases.⁶

• Syphilis, in contrast to gonorrhea and chlamydia, is most common among adults but remains a major problem for teenagers in developing countries.⁶ In rural Nigeria, for example, nearly 3% of sexually active teenagers have active syphilis.⁴

• Trichomonal infections are the most common curable STD worldwide, representing more than half of all treatable STD cases. Adolescents make up a disproportionate share of these cases.⁶ In Nigeria, nearly one-fourth of adolescents have been identified with this infection.⁴

• Bacterial vaginosis is a common condition among sexually active women though its prevalence among adolescents is not specifically known.

• Although generally less prevalent among young adults, infection with the herpes simplex virus nevertheless affects adolescents, often leading to genital ulceration.⁶

• Adolescents have a higher prevalence of genital human papilloma virus (HPV) than other age groups. ¹⁴ One US study showed that up to one-half of sexually active young women have cytologic evidence of infection, even though there is less evidence of external genital warts.⁵

• Hepatitis B virus is widespread, especially in Asia, and has possibly severe health consequences for both adolescents and their offspring.⁶

• About one-half of all human immunodeficiency virus (HIV) infections occur among men and women 24 and younger. Up to 60 % of new infections in developing countries occur among 15-24-year-olds.¹⁹ Twice as many young women as men in this age-group are newly infected. ¹⁹ In rural Tanzania, females aged 15-24 show the highest HIV infection rate.¹⁰

For biological, behavioral, and cultural reasons, young people are at especially high risk of contracting STDs, including HIV:

• Sizable numbers of adolescents are sexually active. In some countries, sexual activity begins in early adolescence, either within or outside of marriage. Young age at first intercourse is a strong risk factor for STDs.^{11, 15}

• Their immature reproductive and immune systems make adolescents more vulnerable to infection by various STD agents.^{6, 12}

• Adolescents, especially young girls, are less able to refuse sex and/or less able to insist on adequate protection. Sometimes sexual activity involves abuse or coercion which, in turn, is linked to young age at first intercourse and to more than one sexual partner—both STD risk factors.¹¹

• Conditions such as poverty, homelessness, political strife, and dislocation, which are increasingly common among young people in developing countries, are associated with sexual abuse or with sexual intercourse exchanged for money or support for basic needs.^{1, 12}

• Young people are ill-informed about STDs, their symptoms, the need for treatment, and where to obtain treatment. Combined with many adolescents’ fear of the medical system, these circumstances often result in avoidance and delays in seeking health care.²⁰ Untreated STDs result in increased susceptibility to HIV infection. ¹⁰

• Reproductive health service providers tend not to welcome adolescent clients. Studies in Antigua, Senegal, and Thailand, among other settings, have found health facilities where adolescent clients are denied privacy and confidentiality, and in which the staff are often rude or moralizing.¹⁸

Early acquisition of an STD increases the probability of recurrent infections because of longer exposure time and the likelihood of a greater number of partners.^{6, 13} Recurrence can exacerbate the health consequences. For example, repeat chamydial infection is more likely than primary infection to be associated with fallopian tube damage.^{16, 17}

• Pelvic inflammatory disease (PID), typically resulting from lower genital tract infection as a result of chlamydia or gonorrhea, is more common among sexually active female adolescents than among women in the older age-groups. PID can result in tubal infertility or ectopic pregnancy.⁶

• Genital human papilloma virus (HPV), which is widespread among adolescents, causes genital warts. In addition, adolescents are at greater risk of developing HPV-associated cancers.¹⁴

• Frequent health consequences of the Hepatitis B virus, in addition to hepatitis, include cancer and cirrhosis. ⁶

• STDs increase the likelihood of negative pregnancy outcomes for both the adolescent mother and her infant. STDs such as syphilis, hepatitis B, and HIV can be transmitted to newborns.⁶ Bacterial vaginosis and trichomoniasis are related to preterm delivery and low birthweight.⁶ These problems are made worse by the fact that fewer adolescents than older women seek prenatal care or other reproductive health services for the treatment of these infections.^{5, 6}

• HIV infection is enhanced by the presence of other STDs. Thus adolescents are at increased risk of HIV infection because of their high STD rates.^{7, 10} While AIDS usually develops fully only after the young person is out of the teenage years, the consequences are nevertheless devastating.

• Many teenagers experience serious psychological consequences as a result of becoming infected with an STD. Typical reactions of guilt and shame often prevent young people from seeking treatment in a timely fashion. ⁹

• Infertility as a result of STDs can lead to men abandoning or divorcing their partners. In some societies, women without support turn to commercial sex for survival.⁷

The author is particularly indebted to Ward Cates for assistance with this In Focus issue, significant portions of which were summarized from Cates W. and McPheeters M. (see bibliography).