STDs in Men Who Have Sex with Men (MSM)

Public Health Impact

Notifiable disease surveillance data on syphilis and data from the Gonococcal Isolate Surveillance Project (GISP) suggest that some STDs in men who have sex with men, including men who have sex with both women and men (MSM) are increasing.^1-4 Because STDs and the behaviors associated with acquiring them increase the likelihood of acquiring and transmitting HIV infection,⁵ the rise in STDs among MSM may be associated with an increase in HIV diagnoses among MSM.⁶

With the exception of reported syphilis cases, most nationally notifiable STD surveillance data do not include information on sexual behaviors; therefore, national trends in STDs among MSM in the United States are not currently available. Furthermore, testing strategies are often suboptimal for detecting STDs in MSM. Testing for gonorrhea and chlamydia in MSM largely focuses on detecting urethral infections, which are more likely to be symptomatic than pharyngeal or rectal infections.⁷ Data from enhanced surveillance projects are presented in this section to provide information on STDs in MSM.

Monitoring Trends in Prevalence of STDs among MSM attending STD Clinics, 1999–2008

From 1999 through 2008, eight U.S. cities participating in the MSM Prevalence Monitoring Project submitted syphilis, gonorrhea, chlamydia, and HIV test data to CDC from 162,019 MSM visits to STD clinics; data from 138,928 MSM visits were submitted from five public STD clinics (Denver, New York City, Philadelphia, San Francisco, and Seattle) and data from 23,091 MSM visits were submitted from three STD clinics in community-based, gay men’s health clinics (Chicago, the District of Columbia, and Houston). In 2009 and beyond, this type of enhanced surveillance data in MSM will be collected through a sentinel surveillance platform called the STD Surveillance Network (SSuN).⁸

The MSM Prevalence Monitoring Project includes data from culture and non-culture tests collected during routine care and reflects testing practices at participating clinics. Tests for gonorrhea included culture, NAATs (or nucleic acid amplification tests) and nucleic acid hybridization tests (DNA probes). Tests for chlamydia included culture, NAATs, and nucleic acid hybridization tests. Nontreponemal syphilis tests included the Rapid Plasma Reagin (RPR) and the Venereal Disease Research Laboratory (VDRL) tests.

All information is based on data collected from clinic visits and may reflect multiple visits by a patient rather than unique individuals. Clinic-specific medians and ranges were calculated for the proportion of tests done and for STD and HIV test positivity.

Gonorrhea

Between 1999 and 2008 the trend in the number of positive gonorrhea tests for all anatomic sites varied by city (Figure W).

In 2008, 71% (range: 57–95%) of MSM visits included testing for urethral gonorrhea; 44%
(range: 3–53%) for rectal gonorrhea; and 64% (range: 4–79%) with testing for pharyngeal gonorrhea.

In 2008, median clinic urethral gonorrhea positivity in MSM was 8% (range: 4–12%), median rectal gonorrhea positivity was 6% (range: 3–11%), and median pharyngeal gonorrhea positivity was 3% (range: 1–12%).

Chlamydia

In 2008, a median of 69% (range: 58–94%) of MSM visiting participating STD clinics were tested for urethral chlamydia, compared to 65% (range: 57–68%) in 1999. In 2008, the median clinic urethral chlamydia positivity was 7% (range: 5–9%).

Syphilis

In 2008, 86% (range: 59–97%) of MSM visiting participating STD clinics had a nontreponemal serologic test for syphilis (RPR or VDRL) performed, compared with 69% (range: 53–93%) in 1999 (Figure X).

Overall, median clinic seroreactivity among MSM tested for syphilis increased from 4% (range: 3–13%) in 1999 to 11% (range: 8–17%) in 2008.

Syphilis seroreactivity is used as a proxy for syphilis prevalence and has been correlated with prevalence of P&S syphilis in this population.³

HIV Infection

Overall, the percent of MSM tested for HIV in STD clinics increased between 1999 and 2008. In 2008, a clinic-specific median of 72% (range: 39–84%) of MSM visiting STD clinics who were not previously known to be HIV-positive were tested for HIV, while 44% (range: 23–55%) were tested in 1999. In 2008, median clinic HIV positivity in MSM was 3%
(range: 2–8%) (Figure Y).

In 2008, median HIV prevalence among MSM, including persons previously known to be HIV-positive and persons testing HIV-positive at their current visit, was 13% (range: 8–18%).

HIV/STDs by Race/Ethnicity

HIV positivity among persons tested for HIV during 2008 varied by race/ethnicity, but was highest in black MSM. The clinic median HIV positivity was 2% (range: 2–3%) in whites; 6% (range: 1–11%) in blacks; and 3% (range: 2–6%) in Hispanics (Figure Z).

In 2008, urethral gonorrhea median positivity was 5% (range: 4–10%) in whites; 11% (range: 7–20%) in blacks; and 9% (range: 4–18%) in Hispanics. Median clinic rectal gonorrhea positivity was 6% (range: 2–13%) in whites; 5% (range: 3–7%) in blacks; and 6% (range: 4–9%) in Hispanics. Median clinic pharyngeal gonorrhea positivity was 3% (range: 1–15%) in whites; 7% (range: 3–11%) in blacks; and 2% (range: 1–8%) in Hispanics (Figure Z).

Median clinic urethral chlamydia positivity was 5% (range: 4–8%) in whites; 8% (range: 6–14%) in blacks; and 6% (range: 4–12%) in Hispanics (Figure Z).

Median clinic syphilis seroreactivity was 9% (range: 7–11%) in whites; 18% (range: 8–25%) in blacks; and 15% (range: 9–20%) in Hispanics (Figure Z).

STDs by HIV Status, STD Clinics

In 2008, median clinic urethral gonorrhea positivity was 11% (range: 8–16%) in HIV-positive MSM and 7% (range: 3–11%) in MSM who were HIV-negative or of unknown HIV status; median rectal gonorrhea positivity was 10% (range: 2–14%) in HIV-positive MSM and 5% (range: 3–11%) in MSM who were HIV-negative or of unknown HIV status; median pharyngeal gonorrhea positivity was 7% (range: 2–10%) in HIV-positive MSM and 3% (range: 1–13%) in MSM who were HIV-negative or of unknown HIV status.

Median urethral chlamydia positivity was 8% (range: 6–14%) in HIV-positive MSM and 7% (range: 4–9%) in MSM who were HIV-negative or of unknown HIV status.

Median syphilis seroreactivity was 33% (range: 22–42%) in HIV-positive MSM and 9% (range: 5–12%) in MSM who were HIV-negative or of unknown HIV status.

Nationally Notifiable Syphilis Surveillance Data

P&S syphilis increased in the United States between 2004 and 2008, with a 67.4% increase in the number of P&S syphilis cases among men and a 78.6% increase in the number of cases among women (Tables 26 and 27). In 2008, the rate of reported P&S syphilis among men (7.6 cases per 100,000 males) was 5.1 times greater than the rate among women (1.5 case per 100,000 females) (Tables 26 and 27). Higher rates in men than women are observed for all racial and ethnic groups.

In 2008, MSM accounted for 63% of P&S syphilis cases in the United States. MSM account for more cases than heterosexual men or women for all racial and ethnic groups (Figure 38). Additional information on syphilis is in the Syphilis section of the National Profile.

Gonococcal Isolate Surveillance Project (GISP)

GISP is a national sentinel surveillance system designed to monitor trends in antimicrobial susceptibilities of strains of Neisseria gonorrhoeae in the United States.^{4, 9}

GISP also reports the percentage of Neisseria gonorrhoeae isolates obtained from MSM. Overall, the proportion of isolates from MSM in selected STD clinics from GISP sentinel sites has increased steadily from 4.0% in 1989 to 22.4% in 2007; in 2008, this proportion decreased slightly to 21.0% (Figure AA). Additionally, the proportion of isolates coming from MSM varies geographically with the largest percentage from the West Coast (Figure BB).

Additional information on GISP is in the Gonorrhea section of the National Profile.

¹ Fox KK, del Rio C, Holmes K, et. al. Gonorrhea in the HIV era: A reversal in trends among men who have sex with men. Am J Public Health 2001;91:959–964.

² Centers for Disease Control and Prevention. Primary and secondary syphilis among men who have sex with men–New York City, 2001. MMWR 2002;51:853–6.

³ Helms DJ, Weinstock HS, et. al. Increases in syphilis among men who have sex with men attending STD clinics, 2000–2005. In: program and abstracts of the 17th Biennial meeting of the ISSTDR, Seattle, WA, July 29-August 1, 2007 [abstract P-608].

⁴ Centers for Disease Control and Prevention. Sexually Transmitted Disease Surveillance 2007 Supplement: Gonococcal Isolate Surveillance Project (GISP) Annual Report 2007. Atlanta, GA: U.S. Department of Health and Human Services.

⁵ Fleming DT, Wasserheit JN. From epidemiologic synergy to public health policy and practice: the contribution of other sexually transmitted diseases to sexual transmission of HIV infection. Sex Transm Infect 1999;75:3–17.

⁶ Hall HI, Song R, Rhodes P, et. al. HIV Incidence Surveillance Group. JAMA, 2008 Aug 6;300(5):520–9.

⁷ Mahle KC, Helms DJ, Golden MR, Asbel LE, Cherneskie T, Gratzer B, Kent CK, Klausner JD, Rietmeijer C, Shahkolahi, Weckerly E, Weinstock HS. Missed Gonorrhea Infections by Anatomic Site Among Asymptomatic Men Who Have Sex with Men (MSM) Attending U.S. STD Clinics, 2002-2006. In: program and abstracts of the 2008 National STD Prevention Conference, Chicago, IL March 10-13, 2008 [abstract A1d].

⁸ Rietmeijer K, Donnelly J,Bernstein K, Bissette J, Martins S, Pathela P, Schillinger J,Stenger M, Weinstock H, Newman L. Here comes the SSuN—Early experiences with the STD Surveillance Network. Public Health Reports (in press)

⁹ Schwarcz S, Zenilman J, Schnell D, et. al. National Surveillance of Antimicrobial Resistance in Neisseria gonorrhoeae. JAMA 1990; 264(11):1413–1417.