Chancroid

Chancroid is a bacterial sexually transmitted infection caused by the fastidious Gram-negative streptobacillus Haemophilus ducreyi. The disease is characterized by painful sores on the genitalia and represents a distinct clinical entity from syphilitic chancres, often referred to colloquially as 'soft chancre' to contrast with the 'hard chancre' of primary syphilis. The pathogen is highly infectious and produces localized disease without systemic manifestations.

Chancroid presents with painful genital ulcers that are typically confined to the genital region without systemic involvement. Men frequently develop a single ulcer, while women more commonly present with four or more ulcers, often with fewer associated symptoms. Approximately one-third of infected individuals develop enlargement of the inguinal lymph nodes, and half of those with lymphadenopathy progress to rupture through the skin, producing draining abscesses known as buboes. The ulceration progresses through characteristic stages from erythematous papule to pustule over 4-7 days, followed by central necrosis and ulcer formation.

Chancroid is found primarily in developing countries and remains most prevalent among low socioeconomic groups with associated commercial sex work. In the United States, the infection has been isolated in up to 10% of genital ulcer cases diagnosed at STI clinics in Memphis and Chicago, though overall infection levels in Western countries are very low, typically around one case per two million population in Canada, France, Australia, and the UK. The disease is considered a marker of sexual network characteristics and healthcare access patterns.

Chancroid spreads from one individual to another solely through sexual contact, with the pathogen entering skin through microabrasions incurred during intercourse. The incubation period ranges from 10 to 14 days before clinical progression. There have been rare reports of accidental infection through the hand, though such transmission is exceptional and not a significant epidemiological concern.

Populations at elevated risk include individuals in developing countries, particularly those in low socioeconomic groups with limited healthcare access. Commercial sex workers represent a key epidemiological reservoir in endemic settings. The disease is strongly associated with sexual network characteristics rather than inherent biological susceptibility, meaning risk is primarily determined by exposure opportunity within high-prevalence populations.

Public health prevention measures for chancroid align with general sexually transmitted infection control strategies, emphasizing barrier protection and partner notification. Source-backed detail on specific prevention protocols is not yet available in the provided material. The disease's association with high-risk sexual networks in resource-limited settings suggests that comprehensive STI prevention programs addressing multiple concurrent infections may be most effective.

Chancroid is not a nationally notifiable disease in most jurisdictions, limiting routine surveillance data availability. Laboratory confirmation remains challenging due to the fastidious nature of H. ducreyi, with culture sensitivity below 80% and no FDA-cleared PCR assays available in the United States. Diagnosis is frequently presumptive based on clinical presentation of multiple painful genital ulcers, particularly in settings where alternative diagnoses have been excluded. The disease's low prevalence in Western settings means that clinicians may have limited experience with recognition and management.

1. 1 Wikidata. chancroid.
2. 2 Wikipedia. Chancroid - Wikipedia.

ICD-10

ICD-11

Total cases

47

Peak month

2021-01

Coverage

2 reporting countries · 2000-01-01 → 2026-05-09