Resurgence of Field Fever in a Temperate Country: An Epidemic of Leptospirosis among Seasonal Strawberry Harvesters in Germany in 2007
Creators: name: Desai, Sarika
name: Treeck, Ulrich Van
name: Lierz, Michael
name: Espelage, Werner
name: Zota, Lavinia
name: Sarbu, Anca
name: Czerwinski, Michal
name: Sadkowska‐Todys, Malgorzata
name: Avdicová, Maria
name: Reetz, Jochen
name: Luge, Enno
name: Guerra, Beatriz
name: Nöckler, Karsten
name: Jansen, Andreas
Publisher: name: Robert Koch-Institut
Year: 2009
Subjects: subject: Adolescent
subject: Humans
subject: Female
subject: Disease Outbreaks
subject: Germany/epidemiology
subject: Male
subject: Middle Aged
subject: Risk Factors
subject: Animals
subject: Antibodies
subject: Adult
subject: Cohort Studies
subject: Retrospective Studies
subject: Leptospirosis/epidemiology
subject: Bacterial/blood
subject: Young Adult
subject: Agricultural Workers' Diseases/epidemiology
subject: Arvicolinae/microbiology
subject: Climate
subject: Enzyme-Linked Immunosorbent Assay/methods
subject: Leptospira/isolation &amp; purification
subject: 610 Medizin

description: Background: Although leptospirosis is a reemerging zoonosis of global importance, outbreaks related to agricultural exposures are primarily situated in tropical countries. In July 2007, a suspected leptospirosis outbreak was recognized among strawberry harvesters from Eastern Europe who were working in Germany. An investigation was initiated to identify the outbreak source and the risk factors for infection. Methods: We conducted a retrospective cohort study with use of a questionnaire administered to harvesters by health authorities in Romania, Slovakia, and Poland. Collected serum samples were tested by microscopic agglutination test and immunoglobulin M enzyme‐linked immunosorbent assay. A case patient was defined as a person who worked in the strawberry field during the period 5 June–8 September 2007 and had leptospirosis‐compatible symptoms and either an antibody titer 1:800 and a positive immunoglobulin M enzyme‐linked immunosorbent assay result (for a confirmed case) or no serological confirmation (for a suspected case). Local rodents were examined for leptospirosis. Results: Among 153 strawberry harvesters, we detected 13 confirmed case patients who had test results positive for antibodies against Leptospira species serogroup Grippotyphosa and 11 suspected case patients (attack rate, 16%). Risk of disease increased with each day that an individual worked in the rain with hand wounds (odds ratio, 1.1; 95% confidence interval, 1.04–1.14) and accidental rodent contact (odds ratio, 4.8; 95% confidence interval, 1.5–15.9). Leptospires of the serogroup Grippotyphosa were isolated from the kidneys of 7 (64%) of 11 voles. Conclusions: This is, to our knowledge, the largest leptospirosis epidemic to occur in Germany since the 1960s. Contact between hand lesions and contaminated water or soil and infected voles was the most likely outbreak source. The unusually warm winter of 2006–2007 supported vole population growth and contributed to this resurgence of leptospirosis in Germany. Because of ongoing climate change, heightened awareness of leptospirosis in temperate regions is warranted.