Gonorrhea

Background

Gonorrhea is the second most commonly-reported notifiable disease in the United States. Infections due to Neisseria gonorrhoeae, like those resulting from Chlamydia 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

From 1975 through 1997, the national gonorrhea rate declined 74% following implementation of the national gonorrhea control program in the mid-1970s (Figure 13). For the past ten years, however, gonorrhea rates appear to have reached a plateau, unfortunately still far from the Healthy People 2010 target of 19 cases per 100,000 population (Figure 14 and Table 1).

Increases in gonorrhea rates in eight western states from 2000 to 2005 have been described among a wide variety of populations in the affected states.² Increases in quinolone-resistant Neisseria gonorrhoeae (QRNG) in 2006 led to changes in national guidelines that now limit the recommended treatment of gonorrhea to a single class of drug, the cephalosporins.³ The combination of increases in gonorrhea morbidity in some populations with increases in resistance and decreased treatment options have reinforced the need for better understanding of the epidemiology of gonorrhea.

Although gonorrhea case reporting is useful for monitoring trends in gonorrhea, true increases or decreases in disease burden may be masked by changes in screening practices (affected by concomitant testing for chlamydia and broader use of urine-based testing), use of diagnostic tests with differing test performance, and changes in reporting practices.⁴

For most areas, the number of gonorrhea cases reported to CDC is affected by many factors, in addition to the occurrence of the infection within the population. As with reporting of other STDs, reporting of gonorrhea cases to CDC is incomplete.⁵ For these reasons, supplemental data on gonorrhea prevalence in persons screened in a variety of different settings are useful in assessing disease burden in selected populations.

Gonorrhea – United States

In 2007, 355,991 cases of gonorrhea were reported in the United States. The rate of reported gonorrhea in the United States was 118.9 cases per 100,000 population in 2007 (Figure 13 and Table 1), a decrease of 0.7% since 2006. Gonorrhea rates have remained relatively stable for over 10 years.

Gonorrhea by Region

As in previous years, in 2007 the South had the highest gonorrhea rate among the four regions of the country (156.0 cases per 100,000 population). Rates in the South and Midwest have remained substantially higher than rates in the Northeast and West. Rates in all regions over the last year have shown little change (Figure 15 and Table 13).

An evaluation of increases in gonorrhea in eight western states from 2000 to 2005 suggested that increases were likely due to a variety of factors such as changes in testing practices (increased volume and use of more sensitive tests) as well as real increases in disease.²

Gonorrhea by State

In 2007, only seven states and Puerto Rico had gonorrhea rates below the HP2010 national target of 19 cases per 100,000 population (Figure 16 and Tables 12 and 13).⁶ This is an increase from 2006 of three states (Montana, North Dakota, and Wyoming) that now meet the HP2010 target.

Gonorrhea by Metropolitan Statistical Area (MSA)

The overall gonorrhea rate in the 50 most populous MSAs was 129.4 cases per 100,000 population in 2007. This is essentially unchanged from 2006. All of these MSAs had rates higher than the HP2010 target of 19 cases per 100,000 population. In 2007, 58.6% of gonorrhea cases were reported by these MSAs (Table 16). Similar to previous years, in 2007 the total gonorrhea rate among females in these MSAs (128.4) remained similar to that among males (129.9) (Tables 17 and 18).

Gonorrhea by County

In 2007, 1,305 (41.6%) of 3,140 counties in the United States had gonorrhea rates at or below the HP2010 national target of 19 cases per 100,000 population. Rates per 100,000 population were between 19 and 100 in 1,099 counties (35.0%), and greater than 100 in 736 counties (23.4%). The majority of counties with greater than 100 cases per 100,000 population were located in the South (Figure 17).

In 2007, 50% of reported gonorrhea cases occurred in just 69 counties or independent cities (Table 19).

Gonorrhea by Sex

Prior to 1996, rates of gonorrhea among men were higher than rates among women. For the seventh consecutive year, however, gonorrhea rates among women and men were similar with rates among women being slightly higher (Figure 14). In 2007, the gonorrhea rate among women was 123.5 and the rate among men was 113.7 cases per 100,000 population (Tables 14 and 15).

Gonorrhea by Age

In 2007, gonorrhea rates continued to be highest among adolescents and young adults. Among females in 2007, 15- to 19 and 20- to 24-year-old women had the highest rates of gonorrhea (647.9 and 614.5, respectively). Among males, the rate was highest in those 20 to 24 years of age  (450.1) (Figure 18 and Table 20).

From 2003 to 2007, slight increases were seen among the age groups under 35 years (4.8% among those 15 to 19 years of age, 2.6% among those 20 to 24 years of age, 5.8% among those 25 to 29 years of age, and 4.3% among those 30 to 34 years of age) (Table 20). Slight decreases were seen among those 35 to 39 years of age (4.6%), and those 40 to 44 years of age (2.0%).

Among females between 15 and 44 years of age (from 2003 to 2007) increases were greatest in those 25 to 29 years of age (10.9%) and those 30 to 34 years of age (11.4%). Among males between 15 and 44 years of age, increases over that time period were seen among those 15 to 19 years of age (9.5%) and those 25 to 29 years of age (1.5%) (Figures 19 and 20, and Table 20).

Gonorrhea by Race/Ethnicity

In 2007, gonorrhea rates remained highest among blacks (662.9 cases per 100,000 population, Table 21B and Figure 21). Similar to recent years, the rate among blacks was 19.1 times greater than the rate among whites (34.7 cases per 100,000 population). Gonorrhea rates were 3.1 times greater among American Indian/Alaska Natives (107.1 cases per 100,000 population), and 2.0 times greater among Hispanics (69.2 cases per 100,000 population) than among whites in 2007. Rates among whites were 1.8 times higher than those among Asian Pacific Islanders (18.8 cases per 100,000 population in 2007 (Figure 21).

Between 2003 and 2007, gonorrhea rates showed no marked changes for any racial or ethnic group, except for a 14.9% decline among Asian Pacific Islanders. There was a  21.8% decline among American Indian/Alaska Natives from 2006 to 2007 (Figure 21 and Table 21B). Additional information on gonorrhea among minority populations can be found in the Special Focus Profiles.

Gonorrhea by Region and Sex

Between 2003 and 2007, gonorrhea rates among women increased 19.1% in the West, 8.7% in the South, and 5.5% in the Midwest. Gonorrhea rates among women decreased 19.7% in the Northeast during the same time period.

Between 2003 and 2007, gonorrhea rates among men increased 15.1% in the West and 1.7% in the South, and decreased 9.4% in the Northeast and 0.5% in the Midwest (Tables 14 and 15).

Gonorrhea by Race/Ethnicity and Sex

From 2003 to 2007, overall rates among white, Hispanic, American Indian/Alaska Native, and black men increased (2.7%, 2.6%, 1.0%, and 0.4% respectively). Gonorrhea rates decreased only among Asian/Pacific Islander males (5.3%) (Table 21B).

Between 2003 and 2007 the overall rate among white, American Indian/Alaska Native, and black women increased (9.0%, 6.1%, and 3.8% respectively). However, decreases were seen among Asian/Pacific Islander and Hispanic women (21.8% and 3.4% respectively) (Table 21B).

Currently, 15- to 19-year-old black women still have the highest gonorrhea rate of any group (2,955.7 per 100,000 population), closely followed by 20- to 24-year-old black women (2,789.2), and 20- to 24-year-old black men (2,451.3).

Gonorrhea by Reporting Source

In 2007, 26.7% of gonorrhea cases were reported by STD clinics (Table A2). This is a slight change from 2003, when 29.9% of gonorrhea cases were reported by STD clinics. In 2007, a higher proportion of male gonorrhea cases were reported from STD clinics than female cases (37.2% and 17.3% respectively) (Figure 22 and Table A2).

Gonorrhea Prevalence Monitoring Project

Gonorrhea test positivity data are available from a variety of settings. Screening criteria and practices may vary by state and over time.

Family Planning Clinics

In 2007, the median state-specific gonorrhea test positivity among 15- to 24-year-old women screened in selected family planning clinics in 43 states, Puerto Rico, and the Virgin Islands was 0.9% (range: 0.1% to 4.9%) (Figure 23). Median gonorrhea positivity in family planning clinics has shown minimal change in recent years (range: 0.8% to 1.1% between 2003 and 2007).

Prenatal Clinics

For women attending selected prenatal clinics in 19 states, Puerto Rico, and the Virgin Islands, the median positivity was 0.8% (range: 0.0% to 3.9%) (Figure D). Median gonorrhea positivity in prenatal clinics has shown minimal change in recent years (range: 0.8% to1.0% between 2003 and 2007).

National Job Training Program

Among 16- to 24-year-old women entering the National Job Training Program in 36 states and Puerto Rico in 2007, the median state-specific gonorrhea prevalence was 3.0% (range: 0.0% to 7.2%) (Figure M). Among men entering the program from 32 states and Puerto Rico in 2007, the median state-specific gonorrhea positivity was 1.1% (range: 0.0% to 4.4%) (Figure N).

Juvenile Corrections

In 2007, the median positivity for gonorrhea by facility in women entering 52 juvenile corrections facilities was 5.3% (range: 0.0% to 13.9%). In men entering 90 juvenile corrections facilities in 2007, the median was 1.0% (range: 0.0% to 4.5%) (Table C).

Gonococcal Isolate Surveillance Project (GISP)

Antimicrobial resistance remains an important consideration in the treatment of gonorrhea.^3,7-14 In 1986, the Gonococcal Isolate Surveillance Project (GISP), a national sentinel surveillance system, was established to monitor trends in antimicrobial susceptibilities of strains of Neisseria gonorrhoeae in the United States among selected STD clinics in approximately 25-30 GISP sentinel sites¹⁴ (Figure 24).

Overall in 2007, 27% of isolates collected from 29 of 30 GISP sites were resistant to penicillin, tetracycline, ciprofloxacin, or some combination of those antibiotics (Figure 25).

Quinolone-resistant N. Gonorrhoeae (QRNG)

Resistance to ciprofloxacin (a fluoroquinolone in the quinolone family of antimicrobials) was first identified in GISP sites in 1991. From 1991 through 1998, fewer than nine quinolone-resistant N. gonorrhoeae (QRNG) isolates were identified each year, and such isolates were identified in only a few GISP clinics. However since 1999 QRNG prevalence has steadily increased, first in Hawaii and the Pacific Islands, then in the Western states, and then among MSM.^7,9,10 In 2007, 891 (14.8%) of 6,009 GISP isolates collected were identified as QRNG, an increase from 2006, when 843/6,089 (13.8%) isolates were identified as QRNG (Figure 26). QRNG isolates were identified from all 29 GISP sites that submitted isolates in 2007. GISP did not receive any isolates from Tripler in 2007.

QRNG by Region

In 2007, QRNG increased most markedly in those regions where prevalence had been relatively low.

In 2007, 20 (28.6%) of 70 isolates submitted from Honolulu demonstrated ciprofloxacin-resistance, a decrease from  34 (35.8%) of 95 isolates in 2006.

From 2006 to 2007, several western sites demonstrated an increase in the number of isolates resistant to ciprofloxacin. In Albuquerque, the prevalence of QRNG more than doubled to 16.7% of isolates collected in 2007 from 7.3% in 2006; in Denver, 17% were resistant to fluoroquinolones in 2007 compared with 15.7% in 2006; in Las Vegas, the prevalence also doubled to 18.7% in 2007 from 8.7% in 2006; in Long Beach, 30.4% were resistant in 2007 compared to 28.4% in 2006; in Orange County, 41% were resistant in 2007 compared with 34.6% in 2006; in Portland, 28.6% were resistant in 2007 compared with 27.2% in 2006; and in San Diego, 36.3% were resistant in 2007 compared with 35.1% in 2006. The prevalence in Los Angeles was relatively the same at 22.4% in 2007. In other western sites such as Phoenix, San Francisco, and Seattle, the prevalence of QRNG decreased slightly during the same time period. In Phoenix, 8.7% of isolates were QRNG when compared with 11.9% in 2006; in San Francisco, the prevalence of QRNG decreased to 31.3% in 2007 from 44.5% in 2006; and in Seattle to 29.3% in 2007 from 31.8% in 2006.

In the South from 2006 to 2007, most of the sites continued to observe increases in the prevalence of QRNG. In Baltimore, QRNG resistance increased to 2% in 2007 from 1.4% in 2006; in Birmingham, the prevalence increased about eight fold to 9.4% in 2007 from 1.1% in 2006; in Dallas, the prevalence increased to 7.5% from 6.1%; in Greensboro, it tripled to 5.3% from 1.7%; in New Orleans it increased to 18.1% from 10.2%; and in Oklahoma City, it increased to 6% from 4.3%. However, in Atlanta, where isolates were submitted from January-April 2007 only, the prevalence of QRNG decreased to 2.6% in 2007 from 5.7% in 2006. In Miami, the prevalence of QRNG  remained about the same in 2007 at 19.6%.

In the Midwest and Northeast there were  dramatic increases in prevalence of QRNG from 2006 to 2007 among several sites. In Chicago, the prevalence of isolates that were resistant to ciprofloxacin doubled to 8.6% in 2007 from 4.1% in 2006; in Cincinnati, the prevalence almost doubled to 1.2% in 2007 from 0.7% in 2006; in Detroit, it increased by five fold to 1.7% in 2007 from 0.3% in 2006; in Minneapolis, it doubled to 10.7% in 2007 from 5.7% in 2006; and in New York City, it also almost doubled to 14.9% in 2007 from 7.6% in 2006. There was a decrease in QRNG prevalence in Cleveland to 0.7% in 2007 from 3.1% in 2006 and in Philadelphia to 29.1% from 30.3%, respectively.

New sites in GISP that identified ciprofloxacin-resistant isolates included Kansas City and Richmond. Kansas City rejoined GISP in September 2007 and observed a QRNG prevalence of 16.4% in 2007. Richmond started collection in November 2007 and QRNG was identified in 17.9% of isolates.

QRNG by Sexual Behavior

The prevalence of QRNG in isolates from MSM slightly decreased from 39% in 2006 to 36% in 2007. During the same time period, the prevalence of QRNG in isolates from heterosexuals increased from 7% to 9% (Figure 27).

As a result of high and continued widespread prevalence of QRNG among MSM and then more recently, among heterosexuals, CDC revised the 2006 CDC STD Treatment Guidelines in April 2007.³ Therefore, CDC states that fluoroquinolones are no longer recommended for use in the United States for the treatment of gonococcal infections and associated conditions such as pelvic inflammatory disease.³

Other Antimicrobial Susceptibility Testing

The proportion of GISP isolates demonstrating decreased susceptibility to ceftriaxone or cefixime has remained very low over time. Overall in GISP, from 1987 to 2007, there have been a total of four isolates with decreased susceptibility to ceftriaxone (all four had minimum inhibitory concentrations (MICs) of 0.5 μg/ml) and 48 isolates with decreased susceptibility to cefixime (MIC range from 0.5-2.0 μg/ml) in GISP. In 2007, there were no isolates identified with decreased susceptibility to ceftriaxone. (Note: Cefixime was discontinued in 2007 from the GISP antibiotic susceptibility panel.)

The proportion of GISP isolates demonstrating elevated MICs to azithromycin has been increasing since GISP began monitoring azithromycin susceptibility in 1992. In 2005, there was a change in the media used for antimicrobial susceptibility testing which resulted in an observational shift of the MIC curve for azithromycin. Thus, the azithromycin MIC for decreased susceptibility was changed from ≥1.0 μg/ml to ≥ 2.0 μg/ml in 2005 and thereafter. In 2007, 0.5% (27/6,009) isolates had azithromycin MIC ≥ 2.0 μg/ml compared to 0.2% (14/6,089) in 2006.

Additional information on antimicrobial susceptibility data and on GISP may be found in the 2007 GISP report⁸ or the GISP website: http://www.cdc.gov/std/GISP

Gonorrhea Among Special Populations

Additional information about gonorrhea in racial and ethnic minority populations, adolescents, MSM, and other at risk populations can be found in the Special Focus Profiles.

Gonorrhea Summary

In summary, the national gonorrhea rate has remained relatively unchanged for approximately ten years. Unfortunately the 2007 rate of 118.9 cases per 100,000 population is still greater than the Healthy People 2010 goal of 19 cases per 100,000 population. Of particular concern are the persistent high rates in some geographic areas, adolescents and young adults, and some racial/ethnic groups.

Although fluoroquinolones are no longer recommended for treatment of gonococcal infections in the U.S., GISP data continues to show widespread increases in QRNG prevalence throughout the country. With only one class of antibiotics recommended for treating gonorrhea, continued monitoring for the emergence of decreased susceptibility and resistance to cephalosporins is critical.

 

¹ Fleming DT, Wasserheit JN. From epidemiological synergy to public health policy and practice: the contribution of other sexually transmitted diseases to sexual transmission of HIV infection. Sex Transm Infect, 1999 Feb;75(1):3–17.

² Centers for Disease Control and Prevention. Increases in gonorrhea - Eight western states, 2000-2005. MMWR 2007;56:222–225.

³ 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, 2007;56: 332–336.

⁴ Centers for Disease Control and Prevention. Gonorrhea -- United States, 1998. MMWR 2000;49:538–42.

⁵ Sexually Transmitted Diseases in America: How Many Cases and At What Cost? Prepared for the Kaiser Family Foundation by: American Social Health Association, December 1998, ASHA: Research Triangle Park, NC, Kaiser Family Foundation: Menlo Park, CA 94025.

⁶ U.S. Department of Health and Human Services. Healthy People 2010. 2nd ed. With Understanding and Improving Health and Objectives for Improving Health. 2 vols. Washington, DC: U.S. Government Printing Office, November 2000.

⁷ Centers for Disease Control and Prevention. Fluoroquinolone-resistance in Neisseria gonorrhoeae, Hawaii, 1999, and decreased susceptibility to azithromycin in N. gonorrhoeae, Missouri, 1999. MMWR 2000;49:833–837.

⁸ 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 (available first quarter 2009).

⁹ Centers for Disease Control and Prevention. Increases in fluoroquinolone-resistant Neisseria gonorrhoeae -- Hawaii and California, 2001 MMWR 2002;51:1041–1044.

¹⁰ 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 2004;53:335–338.

¹¹ Centers for Disease Control and Prevention. Sexually Transmitted Diseases Treatment Guidelines, 2006. MMWR, 2006;55(No.RR-11).

¹² Wang SA, Lee MV, Iverson CJ, Ohye RG, Whiticar PM, Hale JA, Trees DL, Knapp JS, Effler PV, Weinstock HS. Multi-drug resistant Neisseria gonorrhoeae with decreased susceptibility to cefixime, Hawaii, 2001. CID 2003;37:849–52.

¹³ Wang SA, Harvey AB, Conner SM, et al. Antimicrobial Resistance for Neisseria gonorrhoeae in the United States, 1988 to 2003: The Spread of Fluoroquinolone Resistance. Annals of Internal Medicine 2007;147:81–89.

¹⁴ Schwarcz S, Zenilman J, Schnell D, et al. National surveillance of antimicrobial resistance in Neisseria gonorrhoeae. JAMA 1990;264:1413–1417.