Sexually Transmitted Diseases, 2011
Active surveillance for gonorrhea and chlamydia involves cross-checking laboratory-reported cases against cases reported by clinicians. Although both laboratories and clinicians are required to report STDs independently of each other, a laboratory-reported case is not considered a case for surveillance purposes until a corresponding case report is submitted by the clinical facility. Case reports contain demographic and clinical information that is not available from laboratory reports. When a laboratory report is received but no corresponding case report is received within 45 days, we mail a reminder letter and case report form to the clinical facility. Active surveillance for syphilis involves immediate follow-up with the clinician upon receipt of a positive laboratory report. Cases of chancroid are monitored through a mostly passive surveillance system. Herpes simplex virus and human papillomavirus infections are not reportable.
Although overall incidence rates for STDs in Minnesota are lower than those in many other areas of the United States, certain population subgroups in Minnesota have very high STD rates. Specifically, STDs disproportionately affect adolescents, young adults, and persons of color.
Chlamydia trachomatis infection is the most commonly reported infectious disease in Minnesota. In 2011, 16,898 chlamydia cases (319 per 100,000 population) were reported, representing a 9% increase from 2010 (Table 3). Adolescents and young adults are at highest risk for acquiring chlamydial infection (Table 4). The chlamydia rate is highest among 20 to 24-year-olds (1,907 per 100,000), with the next highest rate among 15 to 19-year-olds (1,385 per 100,000). The incidence of chlamydia among adults 25 to 29 years of age (719 per 100,000) is considerably lower but has increased in recent years. The chlamydia rate among females (443 per 100,000) is more than twice the rate among males (193 per 100,000), a difference most likely due to more frequent screening among women. The incidence of chlamydia infection is highest in communities of color (Table 4). The rate among blacks (1,768 per 100,000) is 11 times higher than the rate among whites (166 per 100,000). Although blacks comprise approximately 5% of Minnesota’s population, they account for 29% of reported chlamydia cases. Rates among Asian/Pacific Islanders (320 per 100,000), Hispanics (434 per 100,000), and American Indians (780 per 100,000) are over two to four times higher than the rate among whites. Chlamydia infections occur throughout the state, with the highest reported rates in Minneapolis (848 per 100,000) and St. Paul (759 per 100,000). While there was an overall increase of 9% across the state in 2011 the greatest increase for chlamydia was seen in the suburban area (metropolitan area excluding Minneapolis and St. Paul) with an increase of 15%, shown in Table 4.
Gonorrhea, caused by Neisseria gonorrhoeae, is the second most commonly reported STD in Minnesota. In 2011, 2,283 cases (43 per 100,000 population) were reported, representing a 5% increase from 2010. This is the first increase in reported gonorrhea cases since 2007 (Table 3). Adolescents and young adults are at with incidence rates of 159 per 100,000 among 15 to 19-year-olds, 227 per 100,000 among 20 to 24-year olds, and 105 per 100,000 among 25 to 29-yearolds. Gonorrhea rates for males (38 per 100,000) and females (48 per 100,000) are comparable. Communities of color are disproportionately affected by gonorrhea, with nearly one half of cases reported among blacks. The incidence of gonorrhea among blacks (420 per 100,000) is 26 times higher than the rate among whites (16 per 100,000). Rates among Asian/Pacific Islanders (15 per 100,000), Hispanics (37 per 100,000), and American Indians (103 per 100,000) are up to six times higher than among whites. Gonorrhea rates are highest in the cities of Minneapolis and St. Paul (Table 4). The incidence in Minneapolis (211 per 100,000) is nearly two times higher than the rate in St. Paul (132 per 100,000), seven times higher than the rate in the suburban metropolitan area (30 per 100,000), and 15 times higher than the rate in Greater Minnesota (14 per 100,000). Geographically in 2011, St. Paul saw the largest increase in cases at 35% and Minneapolis saw an 8% increase in cases. The emergence of quinolone-resistant N. gonorrhoeae (QRNG) in recent years has become a particular concern. Due to the high prevalence of QRNG in Minnesota as well as nationwide, quinolones are no longer recommended for the treatment of gonococcal infections.
Surveillance data for primary and secondary syphilis are used to monitor morbidity trends because they represent recently acquired infections. Data for early syphilis (which includes primary, secondary, and early latent stages of disease) are used in outbreak investigations because they represent infections acquired within the past 12 months and signify opportunities for disease prevention.
Primary and Secondary Syphilis
The incidence of primary/secondary syphilis in Minnesota is lower than that of chlamydia or gonorrhea (Table 3), but has remained elevated since an outbreak began in 2002 among men who have sex with men (MSM). In 2011, there were 139 cases of primary/ secondary syphilis in Minnesota (2.6 cases per 100,000 persons). This represents a decrease of 8% compared to the 149 cases (2.8 per 100,000 population) reported in 2010.
In 2011, the number of early syphilis cases increased by 16%, with 260 cases occurring compared to 224 cases in 2010. The incidence remains highly concentrated among MSM. Of the early syphilis cases in 2011, 246 (95%) occurred among men; 218 (88%) of these men reported having sex with other men; 57% of the MSM diagnosed with early syphilis were co-infected with HIV.
Chancroid continues to be very rare in Minnesota. No cases were reported in 2010. The last case was reported in 1999.
- For up to date information see>> Sexually Transmitted Diseases (STDs)
- Full issue>> Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2011