Experimental Infection of Human Volunteers with Haemophilus ducreyi: Fifteen Years of Clinical Data and Experience

• Published in: The Journal of infectious diseases Vol. 199; no. 11; pp. 1671 - 1679
• Main Authors: Janowicz, Diane M., Ofner, Susan, Katz, Barry P., Spinola, Stanley M.
• Format: Journal Article
• Language: English
• Published: Oxford The University of Chicago Press 01.06.2009; University of Chicago Press; Oxford University Press
• Subjects: Adolescent; Adult; Aged; Bacteria; Bacteriology; Biological and medical sciences; Chancroid; Chancroid - genetics; Chancroid - microbiology; Chancroid - pathology; Chancroid - transmission; Disease models; Dosage; Experimental infection; Female; Fundamental and applied biological sciences. Psychology; Haemophilus ducreyi; Haemophilus ducreyi - pathogenicity; Human experimentation; Human immunodeficiency virus 1; Humans; Infections; Infectious diseases; Male; Medical sciences; Men; Microbiology; Middle Aged; Miscellaneous; Recurrence; Scars; Skin Diseases, Vesiculobullous - pathology; Volunteerism; Young Adult; Pasteurellaceae; Human; Infection; Experimental disease; Microbiology; Bacteria; Haemophilus ducreyi
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/598966

Haemophilus ducreyi causes chancroid, which facilitates transmission of human immunodeficiency virus type 1. To better understand the biology of H. ducreyi we developed a human inoculation model. In the present article, we describe clinical outcomes for 267 volunteers who were infected with H. ducreyi. There was a relationship between papule formation and estimated delivered dose. The outcome (either pustule formation or resolution) of infected sites for a given subject was not independent; the most important determinants of pustule formation were sex and host effects. When 41 subjects were infected a second time, their outcomes segregated toward their initial outcome, confirming the host effect. Subjects with pustules developed local symptoms that required withdrawal from the study after a mean of 8.6 days. There were 191 volunteers who had tissue biopsy performed, 173 of whom were available for follow-up analysis; 28 (16.2%) of these developed hypertrophic scars, but the model was otherwise safe. Mutant-parent trials confirmed key features in H. ducreyi pathogenesis, and the model has provided an opportunity to study differential human susceptibility to a bacterial infection