Gonococcal Isolate Surveillance Project (GISP)

The Gonococcal Isolate Surveillance Project (GISP) was established in 1986 to monitor antimicrobial resistance (AR) trends in Neisseria gonorrhoeae in the US. GISP is a collaborative project among selected sexually transmitted disease (STD) clinics and their state or local public health authorities, and regional laboratories participating in the Antibiotic Resistance Laboratory Network (ARLN), and CDC.

GISP collects N. gonorrhoeae specimens from the first 25 men diagnosed with urethral gonorrhea attending participating STD clinics in selected US cities each month. Participating ARLN regional laboratories test the specimens for resistance to the following antibiotics: azithromycin, cefixime, ceftriaxone, ciprofloxacin, gentamicin, penicillin, and tetracycline. These are antibiotics which either are currently or were previously used for gonorrhea treatment. The ability of the bacteria to resist the effect of the antibiotics in the laboratory is measured, and the results are interpreted according to criteria recommended by the Clinical and Laboratory Standards Institute. The results of these tests are then transmitted to CDC where they are collated and analyzed. GISP provides susceptibility trends data used to directly informing gonorrhea treatment recommendations.

GISP, the main surveillance system in the US for monitoring resistant gonorrhea, has expanded in recent years to help improve the ability to detect changes in susceptibility patterns in extragenital anatomic sites of infection and in females. In 2017, GISP expanded in a subset of STD clinics to conduct N. gonorrhoeae surveillance in non-urethral specimens (i.e., pharynx, rectum, and endocervix). The Enhanced Gonococcal Isolate Surveillance Program (eGISP) was established to help understand if the pharynx and/or rectum may be anatomic niches that select for or foster resistance and to evaluate if antibiotic susceptibility patterns may vary between men and women.

In 2021, a new molecular testing component was added to eGISP to include the evaluation of known resistance-associated genetic markers. This molecular surveillance project was added to improve the identification of resistant gonorrhea in a culture-independent manner. Culture remains the best way to detect strains with reduced susceptibility to antibiotics used to treat gonorrhea, but molecular surveillance has the potential to increase the availability of resistant gonorrhea detection in the US, especially in locations without culture capacity.

Regional Laboratories and Sentinel Sites (2023 – 2024)
Map of the 2023-24 GISP sites
Published Reports Using GISP Data
CDC GISP Contact Information
  • For questions about the Gonococcal Isolate Surveillance Project, please email:
Suspected Gonorrhea Treatment Failure Consultation Form

Healthcare providers and health departments can report suspected gonorrhea cephalosporin treatment failure or any N. gonorrhoeae specimen with decreased cephalosporin susceptibility through the Suspected Gonorrhea Treatment Failure Consultation Form.

For questions about reporting a suspected treatment failure or resistant case, please email: GCFAILURE@cdc.gov