STD Quarterly

Despite progress, STD numbers continue to rise; diseases remain a major challenge

Chlamydia, syphilis, gonorrhea cases increase for second year in a row

Review the number of sexually transmitted diseases (STDs) detected in your patient population over the last year. Have the numbers gone up? If so, don't be surprised. National numbers from 2006 show that cases of chlamydia, as well as gonorrhea and syphilis, continued to increase in the United States for the second year in a row, according to a new report by the Centers for Disease Control and Prevention (CDC).1

The CDC estimates that approximately 19 million STD infections occur each year in the United States, with almost half among young people ages 15 to 24.2 Young women, racial and ethnic populations, and men who have sex with men (MSM) are particularly hard hit by these diseases, says John Douglas Jr., MD, director of the Division of STD Prevention in the CDC's National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention. STDs can have serious health consequences, particularly if they are undiagnosed and left untreated, he notes.

Many cases of notifiable STDs go undiagnosed, and some highly prevalent viral infections, such as human papillomavirus and genital herpes, are not reported at all, notes the CDC.1 In releasing its new publication, 2006 STD Surveillance Report, the CDC focused special attention on trends in three notifiable STDs: chlamydia, gonorrhea, and syphilis.

How to stem chlamydia?

The national rate of reported chlamydia in 2006 was 347.8 cases per 100,000 population, an increase of 5.6% from 2005.1 While recent data underscore the impact of innovative screening and prevention strategies, clinicians must continue to adapt to meet new challenges in detecting and treating the disease, says Stuart Berman, MD, chief of the epidemiology and surveillance branch in the CDC's Division of STD Prevention.

Chlamydia screening for women under the age of 26 is critical, says Berman. While the CDC recommends screening for this group, such recommendations are not always implemented, he notes.

"Studies show that chlamydia screening is one of the most effective, yet underutilized, prevention tools," says Berman. "We have seen expanded opportunities for chlamydia screening in recent years, but many young women remain untested."

Simple systems-level changes by clinicians can lead to a significant increase in the number of women screened, notes Berman. For example, placing chlamydia test materials next to Pap test materials during an exam can remind a provider to offer the test and make access to materials convenient, he states.

Recent studies indicate that many women treated for chlamydia may become reinfected by their male partners;3,4 approaches that help facilitate treatment of these partners may help reduce reinfection, says Berman.

"For example the patient herself may help deliver treatment to the partner," states Berman. "This sort of approach is known as expedited partner therapy, and CDC has recommended that it be available and considered by clinicians as an additional strategy to combat reinfection."

Screening and treating men for chlamydia may help decrease transmission to women, says Berman. Several STD programs are conducting such screening, he notes. The CDC has issued guidance that helps STD programs decide which populations of men to test and has indicated that the highest risk populations include men in correctional facilities, he notes. (Editor's note: The CDC convened an external consultation in March 2006 to address male chlamydia screening. To download a free copy of the consultation results, go to the CDC STD web page, Under "STD Topics," click on "Chlamydia and LGV." Under "Treatment," click on "Male Chlamydia Screening Consultation.")

Keep eye on syphilis

While the rate of primary and secondary (P&S) syphilis in the United States decreased throughout the 1990s, national figures show an increase over the past six years. Between 2005 and 2006, the national P&S syphilis rate increased 13.8%, from 2.9 to 3.3 cases per 100,000 population, and the number of cases increased from 8,724 to 9,756.1

To tackle the challenge, the CDC released in May 2006 its updated National Plan to Eliminate Syphilis. The plan is designed to sustain efforts in populations traditionally at risk, including heterosexual and minority populations, as well as increased efforts among men who have sex with men, says Berman. (Editor's note: To review the CDC's updated plan, go to the CDC Syphilis Elimination Effort site, Under "Plans," click on "National." Also, click on "SEE Toolkit" and then "Health Care Provider Materials" for free resources, such as a physician pocket guide on syphilis.)

"This plan will improve surveillance data and increase local capacity to respond to new outbreaks. Additionally, it will prioritize and target innovative interventions for populations at risk," notes Berman. "Finally, the National Plan will improve accountability and outcomes of syphilis elimination efforts with evidence-based approaches, training, and research to enhance prevention and control efforts."

Get a grip on gonorrhea

Public health officials also are keeping a watchful eye on the spread of gonorrhea, the second most commonly reported infectious disease in the United States. According to the CDC, 358,366 cases were reported in 2006. Following a 74% decline in the rate of reported gonorrhea from 1975 through 1997, overall gonorrhea rates plateaued, then increased for the past two years, the agency reports.1 In 2006, the gonorrhea rate was 120.9 cases per 100,000 population, which represented an increase of 5.5% since 2005.

The racial disparities in diagnoses of gonorrhea are stark, says Douglas. In 2006, African-Americans accounted for more than two-thirds (69%) of reported cases. American Indians and Alaskan Natives had the second highest rate of infection, followed by Hispanics. In June 2007, the CDC convened a consultation to address STD disparities in African-American communities as part of its accelerated efforts to bring community leaders and other partners together to address racial and ethnic disparities in STD rates.1

The South continues to record the highest gonorrhea rate among the four regions of the country, according to the CDC.1 Infection rates rose in the region for the first time in eight years, increasing 12.3% between 2005 and 2006 from 141.8 to 159.2 per 100,000 population. Researchers also are concerned about continued increases in the West, where the rate of reported gonorrhea cases rose 2.9% between 2005 and 2006, from 80.5 to 82.8 per 100,000.

Based on preliminary 2006 data that showed widespread fluoroquinolone-resistance among heterosexual and MSM populations, the CDC revised its gonorrhea treatment guidelines in April 2007. The agency no longer recommends that the fluoroquinolone class of antibiotics be used to treat any cases of gonorrhea in the United States.

With the loss of fluoroquinolones, recommended gonorrhea treatments are limited to a single class of antibiotics — cephalosporins. Although 2006 data show no indication of cephalosporin resistance, increased monitoring for emerging resistance and accelerated research into new treatments are needed to continue the nation's progress in stemming the spread of STDs, the CDC states.


  1. Centers for Disease Control and Prevention. 2006 STD Surveillance Report. Accessed at
  2. Weinstock H, Berman S, Cates W Jr. Sexually transmitted diseases among American youth: Incidence and prevalence estimates, 2000. Perspect Sex Reprod Health 2004; 36:6-10.
  3. Klinger E, Pathela P, Cordova D, et al. Burden of repeat Chlamydia trachomatis infection in young women in New York City. Presented at the 2006 National STD Prevention Conference. Jacksonville, FL. May 8-11, 2006.
  4. Chow J, Guo J, Gilson D. Repeat chlamydia and gonorrhea infection using case-based surveillance reports and laboratory-based prevalence monitoring data, California, 2003-2004. Presented at the 2006 National STD Prevention Conference. Jacksonville, FL. May 8-11, 2006.