Haemophilus ducreyi

Taxobox
color = lightgrey
name = "Haemophilus ducreyi"

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image_width = 240px
image_caption = Photomicrograph of "H. ducreyi"
regnum = Bacteria
phylum = Proteobacteria
classis = Gamma Proteobacteria
ordo = Pasteurellales
familia = Pasteurellaceae
genus = "Haemophilus"
species = "H. ducreyi"
binomial = "Haemophilus ducreyi"
binomial_authority = (Neveu-Lemaire 1921)
Bergey et al. 1923

"Haemophilus ducreyi" is a fastidious Gram-negative streptobacillus causing the sexually transmitted disease chancroid characterized by painful sores on the genitalia.

Haemophilus ducreyi is responsible for chancroid, the commonest cause of genital ulceration worldwide. It starts as an erythematous papular lesion which breaks down into a painful bleeding ulcer with a necrotic base and ragged edge.