Leptospirosis Incidence Post-Flooding Following Storm Daniel: The First Case Series in Greece

The present study investigates the public health impact of flooding on leptospirosis incidence after Storm Daniel in Thessaly, Greece, in September 2023. A notable increase in cases was observed, with seven cases of female patients and a mean age of 40.2 years, indicating a significant risk among working-age adults. From the end of September to the beginning of November 2023, a total of 35 patients from flood-prone areas presented to the Emergency Department of the Tertiary University Hospital of Larissa. Diagnosis of leptospirosis was established by meeting the criteria suggested by the national public health organisation (EODY)-compatible clinical course, epidemiological exposure, molecular and serologic confirmation by the detection of immunoglobulin M antibodies to leptospira spp. using a commercially available enzyme-linked immunosorbent assay and real-time quantitative PCR for the molecular detection of leptospira. The larger part (84.6%) of leptospirosis cases were associated with contact with floodwater. The majority of these patients (71.4%) were from the prefecture of Larissa, followed by 14.3% from the prefecture of Karditsa, 8.6% from the prefecture of Trikala, and 5.7% from the prefecture of Magnesia. Occupational exposure and urbanisation were key risk factors. The most prevalent clinical feature was rash (69.2%), followed by fever (61.5%) and myalgia (30.7%). The findings emphasise the need for robust public health strategies, improved sanitation, rodent control, and protective measures for sanitation workers. The data highlight the broader implications of climate change on public health and the necessity for ongoing surveillance and community education to mitigate future outbreaks.