Gonorrhea

Background

Gonorrhea is the second most commonly reported notifiable disease in the United States. Infections due to Neisseria gonorrhoeae, like those resulting from C. trachomatis, are a major cause of PID in the United States. PID can lead to serious outcomes in women, such as tubal infertility, ectopic pregnancy, and chronic pelvic pain. In addition, epidemiologic and biologic studies provide strong evidence that gonococcal infections facilitate the transmission of HIV infection.¹

During 1975–1997, the national gonorrhea rate declined 74% after implementation of the national gonorrhea control program in the mid-1970s (Figure 14). During 1996–2006, the rate fluctuated at about 115 cases per 100,000 population. During 2006–2009, it decreased from 119.7 cases per 100,000 population to 99.1 cases (Table 1).

During 2006–2009, decreases in gonorrhea rates were seen in all racial/ethnic groups, in all age groups, and in both males and females (Figure 15). During 2008–2009, rate decreases were seen in 84% (42/50) of states.

In 2007, increases in quinolone-resistant N. gonorrhoeae (QRNG) led to changes in national guidelines that now limit the recommended treatment of gonorrhea to a single class of drug, the cephalosporins.² The combination of persistently high gonorrhea morbidity in some populations, along with increases in resistance and decreased treatment options, has reinforced the need to better understand the epidemiology of gonorrhea.

Although gonorrhea case reporting is useful for monitoring disease trends, true increases or decreases in the burden of the disease may be masked by changes in screening practices (e.g., concomitant testing for chlamydia and broader use of urine-based testing), changes in reporting practices, and the use of diagnostic tests with different test performance.³

For most states, the number of gonorrhea cases reported to CDC is affected by many factors in addition to the actual occurrence of the infection within the population. As with other STDs, reporting of gonorrhea cases to CDC is incomplete.⁴ For these reasons, supplemental data on gonorrhea prevalence in persons screened in a variety of settings are useful in assessing the burden of the disease in selected populations.

Gonorrhea—United States

In 2009, a total of 301,174 cases of gonorrhea were reported in the United States, a rate of 99.1 cases per 100,000 population (Figure 14, Table 1). This is a rate decrease of 10.5% since 2008.

Gonorrhea by Region

In 2009, as in previous years, the South had the highest gonorrhea rate (133.2 cases per 100,000 population) among the four regions of the country, and rates in the South and Midwest remained higher than rates in the Northeast and West. Rates in all regions have decreased during the past 2 years (Figure 16, Table 13).

Gonorrhea by State

In 2009, gonorrhea rates per 100,000 population by state ranged from 7.2 in Idaho to 246.4 in Mississippi (Figure 17, Table 12). During 2008–2009, 84% (42/50) of states reported a decrease in gonorrhea rates.

Gonorrhea by Metropolitan Statistical Area

The overall gonorrhea rate in the 50 most populous MSAs was 110.4 cases per 100,000 population in 2009. This is a decrease from the rate of 120.4 cases per 100,000 population in 2008. In 2009, 60.2% of gonorrhea cases were reported by these MSAs (Table 16). Similar to previous years, the total gonorrhea rate among females in these MSAs in 2009 (111.1) remained similar to that in males (109.1) (Tables 17 and 18).

Gonorrhea by County

In 2009, a total of 1,405 counties (44.7%) in the United States had a rate less than or equal to 19 cases per 100,000 population. Rates ranged from 19.0 to 100.0 in 1,129 counties (35.9%) and more than 100.0 in 607 counties (19.3%). Most counties with more than 100 cases per 100,000 population were located in the South (Figure 18).

In 2009, 50% of reported gonorrhea cases occurred in just 63 counties or independent cities (Table 19).

Gonorrhea by Sex

Before 1996, gonorrhea rates among men were higher than rates among women. Since that time, rates have been similar among women and men, but during the past 3 years, an increasing trend shows slightly lower rates among men (Figure 15). In 2009, the gonorrhea rate was 105.5 cases per 100,000 population among women and 91.9 among men (Tables 14 and 15).

Gonorrhea by Age

In 2009, gonorrhea rates continued to be highest among adolescents and young adults. In 2009, women aged 15–19 and 20–24 years had the highest rates of gonorrhea (568.8 and 555.3, respectively). Among men, the rate was highest among those aged 20–24 years (407.5) (Figure 19, Table 20).

During 2005–2009, gonorrhea rates decreased in all age groups (Table 20). The largest decreases were among those aged 40–44 years (33.4%), 65 years or older (33.3%), and 35–39 years (29.8%). The smallest decreases were among those aged 20–24 years (5.2%) and 15–19 years (6.1%).

These decreases were reported for both males and females. In males, the largest decreases were among those aged 65 years or older (34.1%) and 40–44 years (33.6%). The smallest decreases were among those aged 15–19 years (2.9%) and 20–24 years (6.2%). In females, the largest decreases were among those aged 40–44 years (33.2%) and 10–14 years (29.1%). The smallest decreases were among those aged 20–24 years (4.3%) and 15–19 years (7.6%).

Gonorrhea by Race/Ethnicity

In 2009, gonorrhea rates remained highest among blacks (556.4 cases per 100,000 population) (Figure 22, Table 21B). Similar to recent years, the rate among blacks was 20.5 times higher than the rate among whites (27.2). Gonorrhea rates were 4.2 times higher among American Indians/Alaska Natives (113.3) and 2.2 times higher among Hispanics (58.6) than among whites in 2009. Rates among whites were 1.5 times higher than those among Asians/Pacific Islanders (18.1) in 2009 (Figure 22, Table 21B).

During 2005–2009, gonorrhea rates decreased in all racial/ethnic groups (22.5% in non-Hispanic whites, 10.2% in blacks, 19.1% in Hispanics, 28.2% in Asians/Pacific Islanders, and 13.8% in American Indians/Alaska Natives) (Figure 22, Table 21B). More information on gonorrhea rates among minority populations can be found in the Special Focus Profiles.

Gonorrhea by Region and Sex

During 2005–2009, gonorrhea rates among women decreased in the West, Northeast, and Midwest and remained essentially unchanged in the South (39.2% decrease in the West, 13.7% in the Northeast, and 12.7% in the Midwest; 0.6% increase in the South) (Table 14). During 2005–2009, rates among men decreased in all regions of the United States (29.1% in the West, 20.2% in the Midwest, 13.2% in the South, and 4.7% in the Northeast) (Table 15).

Gonorrhea by Race/Ethnicity and Sex

During 2005–2009, overall gonorrhea rates decreased among men in all racial/ethnic groups (31.8% in Asians/Pacific Islanders, 22.1% in whites, 16.5% in Hispanics, 15.6% in blacks, and 15.1% in American Indians/Alaska Natives) (Table 21B).

During 2005–2009, overall gonorrhea rates decreased among women in all racial/ethnic groups (24.8% in Asians/Pacific Islanders, 22.6% in whites, 21.3% in Hispanics, 13.2% in American Indians/Alaska Natives, and 4.6% in blacks) (Table 21 B).

In 2009, black women aged 15–19 years had the highest gonorrhea rate of any group (2,613.8 per 100,000 population). Black women and black men aged 20–24 years had similar rates (2,548.7 and 2,168.9, respectively).

Gonorrhea by Reporting Source

In 2009, 22.6% of gonorrhea cases were reported by STD clinics (Table A2). This is a decrease from 2005, when 28.1% of gonorrhea cases were reported by STD clinics. In 2009, a higher proportion of male gonorrhea cases than female cases (31.8% and 14.9%, respectively) were reported from STD clinics (Figure 23, Table A2). Among males, 35.0% of cases with known reporting source came from STD clinics.

Other common reporting sources for males were private physicians/HMOs (22.8%), other health department clinics (7.5%), family planning clinics (2.9%), and emergency rooms (5.0%) (Figure 24). Among females, the most common reporting source was private physicians/HMOs (30.9%), followed by STD clinics (16.7%), family planning clinics (9.1%), other health department clinics (8.1%), and emergency rooms (5.8%).

Prevalence Monitoring

Positivity data from gonorrhea tests are primarily available from family planning clinics. Screening criteria and practices vary by state and over time.

In 2009, the median state-specific gonorrhea test positivity among women aged 15–24 years screened in selected family planning clinics in 46 states, the District of Columbia, Puerto Rico, and the Virgin Islands was 1.0% (range: 0.0% to 3.4%) (Figure 25).

Gonococcal Isolate Surveillance Project

Antimicrobial resistance remains an important consideration in the treatment of gonorrhea.^3,5–12 In 1986, the Gonococcal Isolate Surveillance Project (GISP), a national sentinel surveillance system, was established to monitor trends in antimicrobial susceptibilities of strains of N. gonorrhoeae in the United States. Data are collected from selected STD clinics at 25–30 GISP sentinel sites and from 4–5 regional laboratories (Figure 26).¹²

With the renewed availability of cefixime, susceptibility testing for this oral cephalosporin antibiotic was restarted in 2009. Susceptibility testing for an additional oral cephalosporin, cefpodoxime, was started in 2009.

Information on the GISP antimicrobial susceptibility criteria used can be found in the Gonococcal Isolate Surveillance Project section of the Appendix, Interpreting STD Surveillance Data.

Susceptibility to Ceftriaxone

Susceptibility testing for ceftriaxone began in 1987. Figure 27 shows the distribution of minimum inhibitory concentrations (MICs) to ceftriaxone among GISP isolates during 2005–2009. An increase was reported in the proportion of isolates with MICs of 0.06 μg/ml, from 0.5% in 2006 to 2.4% in 2009. No increases were observed at higher MIC values.

The GISP has reported four isolates with decreased susceptibility to ceftriaxone, and all four had MICs of 0.5 μg/ml. The locations and years of these isolates were San Diego, 1987; Cincinnati, 1992 and 1993; and Philadelphia, 1997. No isolates with decreased susceptibility to ceftriaxone were seen in 2009.

Susceptibility to Cefixime

Susceptibility testing for cefixime began in 1992, was discontinued in 2007, and was restarted in 2009. Figure 28 displays the distribution of MICs to cefixime among GISP isolates in 2005, 2006, and 2009. An increase was reported in the proportion of isolates with MICs greater than or equal to 0.06 μg/ml, from 3.4% in 2005 to 8.3% in 2009.

Since 2000, the GISP has reported 11 isolates with decreased susceptibility to cefixime, and all had MICs of 0.5 μg/ml. Four isolates with decreased susceptibility to cefixime (MIC = 0.5 μg/ml) were reported in 2009 from Chicago, Honolulu, Los Angeles, and Portland.

Susceptibility to Cefpodoxime

GISP began monitoring cefpodoxime susceptibility in 2009. Of 5,630 GISP isolates tested for cefpodoxime susceptibility in 2009, 58.1% had MICs to cefpodoxime less than or equal to 0.015 μg/ml, 39.8% had MICs of 0.03–0.125 μg/ml, and 1.3% had MICs of 0.250–0.5 μg/ml. There were 46 (0.8%) isolates with decreased susceptibility to cefpodoxime (MICs of 1.0–2.0 μg/ml).

Susceptibility to Azithromycin

GISP began monitoring azithromycin susceptibility in 1992. Figure 29 shows the distribution of MICs to azithromycin among GISP isolates during 2005–2009. The proportion of GISP isolates with MICs of 0.5 μg/ml and 1.0 μg/ml to azithromycin increased during 2005–2008 and decreased in 2009. In 2009, five isolates had MICs of 8.0 μg/ml, and two isolates had MICs of 16.0 μg/ml.

Susceptibility to Spectinomycin

All isolates were susceptible to spectinomycin in 2009. GISP has reported five spectinomycin-resistant isolates—from St. Louis in 1988, Honolulu in 1989, San Francisco in 1989, Long Beach in 1990, and West Palm Beach in 1994.

Susceptibility to Ciprofloxacin

Resistance to ciprofloxacin (a fluoroquinolone in the quinolone family of antimicrobials) was first identified at GISP sites in 1991. However, since 1999, QRNG prevalence has steadily increased, first in Hawaii and the Pacific Islands, then in the Western states, then among MSM,^6,8,9 and eventually among all populations in all regions of the United States.2

In 2009, a total of 542 (9.6%) of 5,630 GISP isolates collected were identified as QRNG (Figure 30). The proportion of GISP isolates identified as QRNG declined in 2008 and 2009 after peaking at 14.8% in 2007.

Quinolone-resistant Neisseria gonorrhoeae by Sexual Behavior

The prevalence of QRNG in isolates from men who have sex with men (MSM) decreased from 33.6% in 2008 to 20.1% in 2009. During the same period, the prevalence of QRNG in isolates from men who have sex with women only (MSW) also decreased from 8.2% in 2008 to 6.0% in 2009.

Other Antimicrobial Susceptibility Testing

Overall in 2009, 23.5% of isolates collected from GISP sites were resistant to penicillin, tetracycline, ciprofloxacin, or some combination of those antibiotics (Figure 31).

Antimicrobial Treatments Given for Gonorrhea

The antimicrobial agents given to GISP patients for gonorrhea therapy are shown in Figure 32. The proportion of GISP patients treated with cephalosporins increased from 95.1% in 2008 to 96.2% in 2009. Among patients treated with cephalosporins, the proportion treated with ceftriaxone 250 mg increased from 15.7% in 2008 to 21.6% in 2009; the proportion treated with ceftriaxone 125 mg decreased from 59.5% in 2008 to 53.7% in 2009. The proportion treated with cefixime increased from 5.1% in 2008 to 13.2%
in 2009.

Conversely, the proportion of GISP patients being treated with fluoroquinolones (ciprofloxacin, ofloxacin, or levofloxacin) declined from 2.2% in 2008 to 0.5% in 2009. Treatment with azithromycin 2 g increased slightly, from 1.2% in 2008 to 1.7% in 2009.

More information about 2009 GISP data can be found at /std/GISP.

Gonorrhea Among Special Populations

More information about gonorrhea in racial and ethnic minority populations, women of reproductive age, adolescents, MSM, and other populations at higher risk can be found in the Special Focus Profiles.

Gonorrhea Summary

The national gonorrhea rate fluctuated at about 115 cases per 100,000 population for 10 years during 1996–2006 and then decreased during 2006–2009. High rates persist in some geographic areas, adolescents and young adults, and some racial/ethnic groups.

The GISP continues to monitor for the emergence of decreased susceptibility and resistance to cephalosporins and for decreased susceptibility to azithromycin.

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2 Centers for Disease Control and Prevention. Update to CDC’s sexually transmitted diseases treatment guidelines, 2006: fluoroquinolones no longer recommended for treatment of gonococcal infections. MMWR Morb Mortal Wkly Rep. 2007;56:332-6.

3 Centers for Disease Control and Prevention. Gonorrhea — United States, 1998. MMWR Morb Mortal Wkly Rep. 2000;49:538-42.

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6 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; 2007.

7 Centers for Disease Control and Prevention. Increases in fluoroquinolone-resistant Neisseria gonorrhoeae — Hawaii and California, 2001. MMWR Morb Mortal Wkly Rep. 2002;51:1041-4.

8 Centers for Disease Control and Prevention. Increases in fluoroquinolone-resistant Neisseria gonorrhoeae among men who have sex with men — United States, 2003, and revised recommendations for gonorrhea treatment, 2004. MMWR Morb Mortal Wkly Rep. 2004;53:335-8.

9 Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines, 2006. MMWR Recomm Rep. 2006;55(No.RR-11).

10 Wang SA, Lee MV, Iverson CJ, Ohye RG, Whiticar PM, Hale JA, et al. Multi-drug resistant Neisseria gonorrhoeae with decreased susceptibility to cefixime, Hawaii, 2001. Clin Infect Dis. 2003;37:849-52.

11 Wang SA, Harvey AB, Conner SM, Zaidi AA, Knapp JS, Whittington WL, et al. Antimicrobial resistance for Neisseria gonorrhoeae in the United States, 1988 to 2003: the spread of fluoroquinolone resistance. Ann Intern Med. 2007;147:81-9.

12 Schwarcz S, Zenilman J, Schnell D, Knapp JS, Hook EW 3rd, Thompson S, et al. National surveillance of antimicrobial resistance in Neisseria gonorrhoeae. JAMA. 1990;264:1413-7.