Copenhageni

Copenhageni is a serovar of Leptospira interrogans, a pathogenic spirochete bacterium that causes leptospirosis in humans and other mammals. It is one of the most widely studied serovars and is named after Copenhagen, Denmark, where it was first described. Leptospira organisms are slender, motile, spiral-shaped bacteria that colonize the renal tubules of reservoir hosts.

In humans, Copenhageni infection occurs through contact with water or soil contaminated with urine from infected animals. The principal reservoir is the urban rat, Rattus norvegicus, though other mammals can harbor it. Transmission can occur during swimming, wading in floodwaters, farming, or occupational exposure to animal urine.

Infection ranges from mild flu-like illness to severe disease. Incubation is typically 7 to 12 days. Common signs include sudden fever, myalgias (notably in the calves), headache, conjunctival suffusion, and sometimes jaundice and kidney dysfunction. Severe leptospirosis, or Weil's disease, may involve hepatic dysfunction, renal failure, hemorrhage, and meningitis.

Diagnosis relies on serology, especially the microscopic agglutination test for serovar Copenhageni, plus molecular methods such as PCR in acute illness. Cultures can detect the organism in later stages. Antibiotic therapy, typically doxycycline or penicillin derivatives, is most effective when started early; severe cases may require intravenous antibiotics and supportive care.

Copenhageni is found worldwide but is particularly associated with urban slums and warm climates where rat populations are dense. Prevention focuses on avoiding exposure to contaminated water, protective equipment for at-risk workers, rodent control, and vaccination of animals. Human vaccines are limited and not widely used in many regions.