Adolescents At Risk

Statistics on HIV/AIDS, STDs and Unintended Pregnancy

Many Illinois adolescents think HIV/AIDS, sexually transmitted diseases (STDs) and unintended pregnancy are health concerns only other people need to worry about. The harsh reality is that everyone is potentially at risk, and the threat of these issues needs to be taken seriously.

Part of the Problem

Behaviors that Put Teens at Risk

  • Nearly half of U.S. high school students have had sexual intercourse; the average age of first intercourse for boys and girls is 15.
  • Although teenagers tend to have sexual relationships with only one partner during any given time, their number of sexual partners adds up over time; almost 25 percent report having sex with four or more partners by 12th grade.
  • A 1991 national survey of adolescent males found condom use to be highest at the beginning of a relationship, declining once the partner is perceived as "safe."
  • Only 35 percent of males and females ages 15 to 17 use a condom during every act of sexual intercourse.
  • One out of 50 high school students reports having injected an illegal drug; many students report using alcohol or drugs when they have had sex.


National Statistics

  • According to the U. S. Centers for Disease Control and Prevention (CDC), an average of 40,000 to 80,000 new cases of HIV are reported each year in the U.S. It is estimated that half of all new infections are among people younger than 25.
  • Compared to the general population, adolescents have one of the fastest increasing rates of HIV infection; an average of two young people are infected with HIV every hour of every day.
  • Through December 2000, CDC statistics show 774,467 reported AIDS cases; 4,061 cases were among teenagers 13 to 19 years of age.
  • Among reported AIDS cases in adolescents 13 to 19 years of age, 50 percent occur in African Americans, 28 percent in Caucasians and 20 percent in Hispanics.

Illinois Statistics

  • In 1998, HIV infection was the sixth leading cause of death in Illinois for persons 25 to 44 years of age -- a large portion of whom likely contracted the virus as adolescents.
  • As of June 1998, a total of 5,406 cases of HIV infection have been reported in Illinois residents ages 20 to 29 – a group likely to have contracted the virus as adolescents.
  • CDC statistics rank Illinois the sixth highest for reported AIDS cases among all states.

Sexually Transmitted Diseases (STDs)

More than 20 diseases can be transmitted sexually. Very few are "reportable" infections due to lack of diagnosis and treatment, but many have serious and costly consequences.

National Statistics

  • Each year one-quarter of the estimated 12 million new cases of STDs, other than HIV, in the U.S. occur among teenagers.
  • Adolescents 15 to 19 years old have some of the highest reported rates of gonorrhea and chlamydia among sexually active people.
  • Many cases of chlamydia and gonorrhea go unreported due to high rate of asymptomatic (showing no symptoms) infections; diagnosis is especially difficult in women. Both diseases can be characterized by burning, frequent urination and discharge, although chlamydia symptoms are much milder than those of gonorrhea.
  • Latest estimates indicate that chlamydia infects 3 million people each year; gonorrhea infects 650,000 people each year.
  • An estimated 20 percent to 40 percent of women infected with chlamydia and 10 percent to 40 percent of women with gonorrhea develop upper genital tract infections or pelvic inflammatory disease (PID); PID is the leading cause of preventable infertility and ectopic pregnancy.
  • Primary syphilis infections are characterized by sores on genitals, rectum, tongue or lips; secondary infections are characterized by body rash (especially on hands and feet), fever, headache and soreness of joints.
  • Each year, there are an estimated 70,000 new cases of syphilis.
  • Fetal or neonatal death occurs in up to 40 percent of pregnant women with untreated syphilis.
  • Human papillomavirus (HPV) is characterized by genital warts. Each year, it is estimated that there are more than 5 milllion new cases of HPV.
  • HPV is the single most important risk factor for cervical cancer; other types of HPV can cause genital warts, for which there is no cure.
  • Genital herpes is characterized by itching, water blisters or open sores in genital area. There are an estimated 1 million new cases of genital herpes each year.
  • There is no cure for genital herpes and symptoms can continue to reoccur.

Illinois Statistics

  • Chlamydia
    • In 2000, Illinois ranked third in number of cases and 19th for rate per 100,000 population among all states for chlamydia infections.
    • In 2000, Illinois adolescents ages 10 to 19 accounted for 12,957 cases of chlamydia (39 percent of total reported cases in Illinois).
  • Gonorrhea
    • In 2000, Illinois ranked third for number of cases and 12th for rate per 100,000 population among all states for gonorrhea infections.
    • In 2000, Illinois adolescents ages 10 to 19 accounted for 5,763 cases of gonorrhea (39 percent of total reported cases in Illinois).
  • Syphilis
    • In 2000, Illinois adolescents ages 10 to 19 accounted for 61 cases of early syphilis (8 percent of total reported cases in Illinois).

Unintended Pregnancy

National Statistics

  • More than 1 million American teenagers become pregnant each year – one of the highest rates of any western industrialized country.
  • One in eight women ages 15 to 19 become pregnant each year.
  • Pregnancy among school-age youth can reduce completed levels of education, employment opportunities and marital stability, and can increase welfare dependency.

Illinois Statistics

  • According to the Illinois Department of Public Aid Teen Parent Services, nearly 4,100 Illinois women younger than 19 draw public assistance every year because of teen pregnancy.
  • In 2000, 11.4 percent of total Illinois births -- or 21,108 babies -- were born to teens.
  • Illinois ranks 18th out of all states for teen birth rates; the Illinois birth rate of 60.0 per 1,000 teens is significantly higher than the national rate of 56.8.

The following fact sheets on HIV/AIDS, STDs and unintended pregnancy are available: African-American Adolescents, Living in a High-risk Population: Hispanic Adolescents, Living in a High-risk Population : Adolescents at Risk, Statistics on HIV/AIDS, STDs and Unintended Pregnancy, Talking to Your Kids about HIV/AIDS, STDs and Unintended Pregnancy

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Illinois Department of Public Health
535 West Jefferson Street
Springfield, Illinois 62761
Phone 217-782-4977
Fax 217-782-3987
TTY 800-547-0466
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