Leptospirosis - 2019

Leptospirosis - 2019

Leptospirosis is a zoonosis, i.e., a disease that is transmitted between animals and humans. The disease is caused by infection with spirochetes from the Leptospira bacterium species. Spirochetes are found naturally in the urine of many mammals, but in Denmark humans mainly become infected from rodent urine. Frequently, the condition is seen in people who have increased contact to rats, such as sewer workers, farmers or private citizens who clean out cellars, e.g. after a flood, EPI-NEWS 34b/11 and 4-5/19.

In 2019, a total of 14 cases of leptospirosis were recorded. Nine of the cases had become infected in Denmark (primarily in South Denmark), and the remaining cases had become infected in Indonesia, Vietnam, South America and Greenland. The distribution of the cases acquired in Denmark may possibly be explained by a heightened local attention to the condition, as rodents are more common in wetlands. Additional details about disease incidence and national monitoring are described in the 2019 Annual Report  and on the SSI’s website.

Leptospirosis is rare in humans, but may cause serious disease and death, EPI-NEWS 28-33/16. Persons who develop influenza-like symptoms, a cold, red eyes and/or petechia after coming into contact with rats, or potentially infected material such as rubbish, manure, freshwater, sewage and waste water or water/mud after floodings and the like should see their doctor for further work-up.

Read more about the disease description, testing, diagnostics and management at the SSI´s website . 

Leptospirosis is individually notifiable on Form 1515. A presentation of the Danish cases and their trend as from 1980 is available at the SSI’s website.

One Health

In 2019, as part of the national implementation of the One Health strategy against infectious diseases, the SSI and the University of Copenhagen jointly assumed responsibility for the Danish veterinary preparedness programme (Danish Veterinary Consortium, DK-VET) which, among others, includes providing advisory services to the Danish Veterinary and Food Administration in connection with One Health monitoring and preparedness services. Thus, the diagnostics for leptospirosis in humans and animals are performed jointly at Statens Serum Institut. This improves the opportunity to compare and identify if infection was transmitted directly from animals to humans or between animals.

Read more about the One Health activities and preparedness services here at the SSI’s website.

(C. Kjelsø, Department of Infectious Disease Epidemiology and Infection, K.A. Krogfelt, C. S. Jørgensen, Department for Virus and Microbiological Special Diagnostics)