Sexually Transmitted Diseases, 2003
Active surveillance for gonorrhea and chlamydia was initiated in January 2002. This process involves crosschecking laboratory-reported cases against cases reported by clinicians. Although both laboratories and clinical facilities are required to report STDs independently of each other, an episode of STD is not considered a case for surveillance purposes until a corresponding case report is submitted by a clinical facility. Additionally, case reports contain critical 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, MDH mails a reminder letter and case report form to the corresponding clinical facility. Cases of syphilis and 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 STD in Minnesota. In 2003, 10,714 cases (218 per 100,000 population) were reported, representing a 6% increase from 2002 (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 (1,253 per 100,000 population), with the next highest rate among 15 to 19- year-olds (927 per 100,000). The incidence of chlamydia among adults 25 to 29 years of age (518 per 100,000) is considerably lower but has increased in recent years. The chlamydia rate among females (317 per 100,000) is more than twice the rate among males (117 per 100,000). This difference probably is due to more frequent screening among women.
The incidence of chlamydia infection is highest in communities of color (Table 4). The rate among blacks (1,490 per 100,000 population) is 14 times higher than the rate among whites (105 per 100,000). Although blacks comprise approximately 4% of Minnesota’s population, they account for 28% of reported chlamydia cases. Rates among Asian/Pacific Islanders (275 per 100,000), American Indians (464 per 100,000), and Hispanics (561 per 100,000) are two to five times higher than the rate among whites.
Chlamydia infections occur throughout the state, with the highest reported rates in Minneapolis (755 per 100,000 population) and St. Paul (618 per 100,000). The incidence in the suburban metropolitan area (156 per 100,000) is similar to that in Greater Minnesota (131 per 100,000).
Gonorrhea, caused by Neisseria gonorrhoeae, is the second most commonly reported STD in Minnesota. In 2003, 3,202 cases (65 per 100,000 population) were reported, representing an increase of 5% from 2002 (Table 3).
Adolescents and young adults are at greatest risk for gonorrhea (Table 4), with incidence rates of 209 per 100,000 population among 15 to 19- year-olds, 321 per 100,000 among 20 to 24-year olds, and 168 per 100,000 among 25 to 29-year-olds. Gonorrhea rates for males (58 per 100,000) and females (72 per 100,000) are comparable. Communities of color are disproportionately affected by gonorrhea, with 46% of cases reported among blacks. The incidence of gonorrhea among blacks (727 per 100,000) is approximately 33 times higher than the rate among whites (22 per 100,000). Rates among American Indians (104 per 100,000) and Hispanics (106 per 100,000) are approximately five times higher than among whites. The rate among Asian/Pacific Islanders (29 per 100,000) is similar to that among whites.
Gonorrhea rates are highest in the cities of Minneapolis and St. Paul (Table 4). The incidence in Minneapolis (359 per 100,000 population) is nearly twice the rate in St. Paul (200 per 100,000), nine times higher than the rate in the suburban metropolitan area (40 per 100,000), and 18 times higher than the rate in Greater Minnesota (20 per 100,000).
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). Forty-seven cases of primary/secondary syphilis (1.0 per 100,000 population) were reported in 2003.
The number of cases of early syphilis increased significantly in 2003, driven by an increase in syphilis cases among white men who have sex with men (MSM). Ninety-two cases of early syphilis were reported in 2003, compared to 82 cases in 2002. Of the 92 early syphilis cases in 2003, 83 (90%) occurred among men; 71 (86%) of these men reported having sex with other men. Almost half (42%) of the MSM diagnosed with early syphilis were co-infected with HIV. Similar increases in syphilis among MSM have been observed in other parts of the Unites States.
No cases of congenital syphilis were reported in Minnesota in 2003 (Table 3).
Chancroid continues to be very rare in Minnesota. No cases were reported in 2003.
Note: For up to date information on Sexually Transmitted Diseases see Sexually Transmitted Diseases (STDs)
Go to full issue: DCN, August 2004: Volume 32, Number 4