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Reporting Obligations

Individuals who have or may have chancroid shall be reported to the local Health Unit.

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Aetiologic Agent

Chancroid is caused by Haemophilus ducreyi, a gram-negative coccobacillus.

Clinical Presentation

Chancroid is an acute, sexually transmitted bacterial infection usually localized in the genital area and characterized clinically by a single or multiple painful, necrotic ulcers that bleed on contact. Ulcers are more frequently found in uncircumcised men (especially clients of sex trade workers). Primary lesions are frequently accompanied by painful, swollen and suppurating regional lymph nodes. In women, asymptomatic carriage is rare, but minimally symptomatic or painless lesions may occur on the vaginal wall or cervix. Chancroid can mimic other genital ulcer diseases, particularly syphilis; however, chancroid lesions are usually painful, and classic primary syphilis chancres are generally painless.

Modes of Transmission

Direct sexual contact with discharge from open lesions and pus from buboes. Autoinoculation to non-genital sites may occur in infected people. It is transmitted only by individuals with ulcerations. Sexual abuse must be considered when chancroid is found in children.

Incubation Period

3–5 days up to 14 days.

Period of Communicability

Chancroid is communicable until the original ulcer(s) and/or discharging regional lymph node are healed. This may take up to several weeks or months without antibiotic treatment. With antibiotic treatment, elimination of H. ducreyi, and lesions heal within 1–2 weeks.

Risk Factors/Susceptibility

Susceptibility is general; the uncircumcised are at higher risk than the circumcised; there is no evidence of natural resistance. Risk factors are:

  • High risk sexual contact with sex trade workers
  • Males who are uncircumcised
  • Infection with H. ducreyi s associated with increased risk of HIV infection
  • The risk of HIV infection increases by 10–50 fold following sexual exposure to an individual with concomitant H. ducreyi and HIV infection

Diagnosis and Laboratory Testing

Specimens of choice for the detection of Haemophilus ducreyi are taken from the base of the ulcer using a calcium alginate or cotton swab, or an aspirate if buboes are present.

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Treatment and Case Management

Chancroid is not known to be endemic in Canada and its appearance should be responded to immediately. Treatment and follow up is under the direction of the attending physician. For treatment of cases and contacts see the “Canadian Guidelines on Sexually Transmitted Infections, evergreen edition”.

All patients diagnosed with chancroid should undergo testing to rule out co-infection with other STI’s, including HIV (at presentation and 3 months later), Lymphogranuloma venereum, HSV, Syphilis, Donovanosis (granuloma inguinale) and gonorrhea.

Patient Information

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Ministry of Health and Long-Term Care, Infectious Diseases Protocol, 2022.

Heymann, D.I., Control of Communicable Disease Manual (19th Ed.), Washington, American Public Health Association, 2008.

Public Health Agency of Canada, Canadian Guidelines on Sexually Transmitted Infections, evergreen edition.

Chancroid | Public Health Ontario