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HIV and Sexually Transmitted Infections HIV and Sexually Transmitted Infections Sexually transmitted infections (STIs) continue to be Untreated chlamydial infection can cause pelvic a significant public health issue in the United States. inflammatory disease in women, which can lead to In fact, most sexually active people will have an STI chronic pelvic pain and infertility. Chlamydial at some point during their lifetime (Satterwhite et infection has also been linked to problems during al., 2013). Including HIV infections, there are an pregnancy and, newborns may become infected estimated 19–20 million new STIs annually in the during birth, which can lead to eye or lung U.S. (CDC, 2013). The prevalence of STIs in the U.S. infections. CDC recommends that all pregnant population in 2008 was estimated at around 110 women be screened for chlamydia (CDC, 2014c). million infections with lifetime direct medical costs estimated at $16 billion (CDC, 2013). Illinois In 2013, there were 63,797 cases of chlamydia Anyone who is sexually active risks exposure to an reported in Illinois or 497 cases per 100,000 th STI. Having unprotected (without use of a latex population. Illinois had the 12 highest rate of condom)vaginal or anal sex increases risk of STI chlamydia infection among the 50 states in 2013 transmission. Oral sex, without usage of a latex (CDC, 2014h). condom or dental dam, can also transmit infection. Additional risk factors including having sexual Sex contact with multiple partners and substance use, Females account for the majority of reported which can inhibit judgment and increase risky chlamydial infections. This is likely due to higher behaviors. screening rates among women. However, with increased availability of urine testing, men are STIs are often asymptomatic and treatment may be increasingly being tested for and diagnosed with delayed. Thus, screening for STIs is an important part chlamydial infection (CDC, 2014h). In 2013, reported of routine health care (CDC, 2014o). Unlike HIV, rates of chlamydial infections were over two-fold most STIs are curable with treatment. However, higher among Illinois women than men with 0.7 antimicrobial resistance has emerged as an issue for chlamydial infections diagnosed per 100 females. the treatment of some STIs. Figure 1. Rate of Reported Chlamydia Cases by Sex, Chlamydia, Syphilis and Gonorrhea Illinois, 2009–2013 In Illinois, chlamydia, gonorrhea, and syphilis are reportable conditions. Because individuals diagnosed with STIs may practice high-risk behaviors, IDPH Female Male Total conducts interventions targeting these high-risk 743 800 715 individuals (see section, “IDPH HIV Programs”). 703 682 700 Interventions include HIV testing and expedited 600 528 506 497 partner therapy, among others. 488 473 400 287 302 285 Chlamydia 263 254 Chlamydia, caused by the bacterium Chlamydia 200 trachomatis, is the most common sexually Cases per100,000 Population transmitted bacterial infection in the United States 0 2009 2010 2011 2012 2013 (CDC, 2014h). Most chlamydial infections are asymptomatic though some men (~10%) and women Source: Illinois Department of Public Health STD Program Data, (~10-30%) may develop symptoms (CDC, 2014c). 2015 2014 ILLINOIS HIV/AIDS EPIDEMIOLOGY PROFILE Race/Ethnicity Figure 3. Rate of Reported Chlamydia Cases by Age Despite a decline in the rate of chlamydial infections at Diagnosis, Illinois, 2013 from 2009 to 2013, non-Hispanic (NH) blacks continued to have the highest infection rate among ≥50 12 all racial/ethnic groups in Illinois. In 2013, the rate 45-49 58 among NH blacks was seven-fold higher than among 40-44 122 NH whites and four-fold higher than among 35-39 226 30-34 477 Hispanics. In 2013, there were 1.5 chlamydial 25-29 1,061 infections for every 100 NH black Illinois residents. 20-24 2,826 15-19 2,216 10-14 77 Figure 2. Rate of Reported Chlamydia Cases by Cases per100,000 Population Race/Ethnicity, Illinois, 2009–2013 5-9 1 0-4 4 NH White NH Black 0 500 1,000 1,500 2,000 2,500 3,000 Hispanic Asian/Pacific Islander 2,000 American Indian/Alaskan Native Source: Illinois Department of Public Health STD Program Data, 2015 1,600 1,781 1,565 NH Black 1,200 Syphilis 800 Hispanic Syphilis is a sexually transmitted disease caused by the bacterium Treponema pallidum. Syphilis is 400 397 348 Cases per100,000 Population 302 239 transmitted person-to-person by direct contact with 89 0 80 a syphilitic sore, known as a chancre (primary 2009 2010 2011 2012 2013 syphilis). Chancres occur mainly in the genital and Source: Illinois Department of Public Health STD Program Data, rectal areas but can also occur on the lips and in the 2015 mouth. Transmission can occur during vaginal, anal, or oral sex and pregnant women with the disease Age at Diagnosis can transmit it to their unborn child (CDC, 2014q). Chlamydial infection rates peak in young adults aged Syphilis can be successfully treated with appropriate 20–24 years. In 2013, almost 3% of young adults in antibiotics; however, treatment does not reverse Illinois aged 20–24 years were diagnosed with organ damage that may have been caused by the chlamydia. bacterium (CDC, 2014q). Sexually active youth are at higher risk of acquiring Untreated syphilis develops in stages and symptoms chlamydia for a combination of behavioral, vary with each stage. The first stage is development biological, and cultural reasons. In 2013, among of the chancre, normally at the location where the sexually active Illinois high school students, 42% bacteria entered the body. The chancre is painless reported not using a condom during last sexual and can be hidden within the vagina or rectum, intercourse (see section, “Youth”) (CDC, 2014a). making it difficult to detect. Secondary syphilis Youth may face barriers, such as transportation or occurs a few weeks after the chancre heals and can stigma, that can reduce access to STI prevention present as a non-itchy rash. Other symptoms of services (CDC, 2014c). Teenage girls and young secondary syphilis include sore throat, fever, and women are at increased risk due to cervical changes swollen lymph nodes. These signs and symptoms that can increase susceptibility to STIs. may disappear within a few weeks or can reoccur. (CDC, 2014c). Without treatment, the disease moves from the second stage to the asymptomatic latent stage. The Did You Know? asymptomatic stage has two phases: early latent stage (within 1 year of infection) and late latent Youth (15–24 years) account for 50% of all new stage (after 1 year). Late latent syphilis is STIs in the U.S., although they represent just noninfectious. Symptoms may never return or may 25% of the sexually experienced population. progress to tertiary (late) syphilis, which occurs in about 15–30% of untreated individuals. In the 2014 ILLINOIS HIV/AIDS EPIDEMIOLOGY PROFILE tertiary stage, the disease may damage the brain, Race/Ethnicity nerves, bones, and other organs and may result in NH blacks had the highest rates of early syphilis death. Tertiary syphilis usually occurs three or more infections from 2009–2013. In 2013, the rate among years after the original, untreated infection (CDC, NH blacks was 2.5 times higher than among 2014q). Hispanics and eight times higher than among NH whites. From 2009–2013, early syphilis infection Among pregnant women, untreated syphilis can rates increased among all racial/ethnic groups in result in complications during pregnancy including Illinois. fetal death. Children born with congenital syphilis can experience serious health effects. CDC Figure 5. Rate of Reported Early Syphilis Cases by recommends that all pregnant women be screened Race/Ethnicity, Illinois, 2009–2013 for syphilis. NH White NH Black Illinois 50 Hispanic Asian/Pacific Islander 45 43.7 In 2013, there were 2,661 cases of any stage of 40 NH Black syphilis and 1,607 cases of early syphilis reported in 35 32.7 Illinois. Twenty-three cases of congenital syphilis 30 were reported or 13.9 cases per 100,000 live births 25 (CDC, 2014h). 20 15 Hispanic 14.6 10 10.1 Cases per100,000 Population Sex 5 NH White 5.3 3.4 Asian/Pacific Islander In Illinois, rates of early syphilis infection are much 0 2009 2010 2011 2012 2013 higher in males than females. Rates among Illinois males have increased steadily since 2009. Nationally, Note: Early syphilis is defined as syphilis diagnosed at the syphilis rates have been increasing overall, after a primary, secondary or early latent stage. long period of decline. The rise in incidence has been Source: Illinois Department of Public Health STD Program Data, 2015 attributed to increased cases among men who have sex with men (MSM). In 2013, MSM accounted for 75% of all primary and secondary syphilis cases in Age at Diagnosis the U.S. (CDC, 2014q). In 2013, early syphilis infection rates peaked in youth aged 20–24 years. Among adults >24 years, infection Figure 4. Rate of Reported Early Syphilis Cases by rates declined with increasing age. Sex, Illinois, 2009–2013 Figure 5. Rate of Reported Early Syphilis Cases by Female Male Total Age at Diagnosis, Illinois, 2013 25 22.5 20.2 20.7 ≥50 4.0 19.3 20 45-49 16.6 16.2 40-44 20.0 15 12.5 35-39 20.9 11.4 11.7 11 30-34 27.4 8.8 10 25-29 31.7 20-24 38.0 5 3.0 2.9 3.0 2.9 15-19 8.2 Cases per100,000 Population 1.7 10-14 0.1 0 Cases per100,000 Population 5-9 0.0 2009 2010 2011 2012 2013 0-4 0.1 0 10 20 30 40 Note: Early syphilis is defined as syphilis diagnosed at the primary, secondary or early latent stage.
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