Nine men treated in Barcelona between December 2025 and March 2026 have been diagnosed with dermatophilosis in a confirmed chain of sexual transmission among people. The study was led by the Microbiology Service and the Drassanes STI Unit of the Infectious Diseases Service of the Vall d'Hebron University Hospital.
The finding breaks with the usual pattern of an infection associated with animals and tropical areas. In these cases, the patients had not had contact with animals nor had they traveled to these environments, and the strain detected is also genetically distinct from that circulating among animals, with a possible greater capacity for infection and transmission among humans.
The Barcelona series confirmed sexual transmission without contact with animals
The nine patients are men who had had sexual relations with other men and presented mild skin lesions in the genital area, groins, thighs, or beard. All evolved favorably after receiving antibiotic treatment and none suffered complications.
Juanjo González, a microbiologist involved in the study, downplayed the alarm despite the change in pattern detected. The specialist focuses on identifying cases and clinically monitoring an infection that until now had not been described with this transmission mechanism among people.
In the research, professionals detected that most episodes had occurred under conditions of close contact and humidity. Attendance at saunas appears as one of the factors that facilitated transmission due to the humid environment.
"It is important for professionals to consider this infection in certain skin conditions, to facilitate its diagnosis and treatment" - Vicente Descalzo, researcher at the Infectious Diseases group, VHIR
Humidity in saunas and shared objects were the focus of recommendations
In addition to direct contact, the team recommends extreme caution with personal items. Juanjo González and Vicente Descalzo urge avoiding sharing razors or towels, as the microorganism can remain on the skin.
Outside of Barcelona, the described pattern no longer appears as an isolated event. Following the publication of the report, other cases with similar characteristics have been identified in Paris, Lyon, and Berlin.
Researchers link this expansion to increased international mobility and transmission circuits reminiscent of those observed during monkeypox. The comparison points to the effect of globalization on the circulation of infections that change environment and mode of contagion.
"The sooner we start treating it, the sooner we will eradicate it" - Vicente Descalzo, researcher at the Infectious Diseases group, VHIR
Juanjo González, microbiologist of the study, maintains that the situation is not alarming, while the report records nine cases detected in Barcelona between December 2025 and March 2026 and the subsequent appearance of diagnoses with the same pattern in Paris, Lyon, and Berlin.