Suspected human-to-human sexual transmission of dermatophilosis
Poinews.com – A recent study, published in early June by a group of epidemiologists from the Hospices Civils de Lyon (HCL), has raised concerns about the potential for human-to-human spread of dermatophilosis through sexual activity. The research, featured in the US-based journal Emerging Infectious Diseases, marks a significant shift in understanding this bacterial zoonosis, which has historically been linked to animal contact.
Unusual Cases in France and Spain
Previously only documented in individuals working with infected livestock such as horses and cattle, dermatophilosis has now been observed in a new context. Between January and June, approximately 40 cases were reported across France and Spain, with 30 of them concentrated in Lyon. The study’s focus narrowed to nine patients who sought medical attention at HCL.
Genomic Evidence and Shared Exposures
Of the nine individuals, seven had engaged in sexual activity at gay saunas in Lyon, often in the same venues, days before symptoms appeared. While direct connections between patients were not confirmed, the researchers concluded that “genomic similarity and shared sexual exposures strongly suggest human-to-human sexual transmission of this zoonotic bacterium.” All affected individuals identified as men who have sex with men in Lyon and Paris.
“Genomic similarity and shared sexual exposures strongly suggest human-to-human sexual transmission of this zoonotic bacterium.”
Symptoms and Treatment
Patients exhibited skin lesions characterized by pustules and crusts, primarily affecting the genital region, torso, mouth, and lower limbs. In contrast to its progression in animals—where it can spread systemically and become life-threatening—none of the human cases required hospitalization. A straightforward antibiotic regimen, occasionally paired with topical antiseptic applications, resulted in swift recovery.
Environmental Factors in Transmission
Scientists propose that the warm, moist environment of saunas likely intensified transmission. These conditions are believed to have encouraged the release of zoospores, microscopic bacteria capable of moving through water and infiltrating the skin. This discovery highlights how human behavior and environmental factors can influence the spread of animal-origin infections.
