Leptospirosis in the Tel Aviv District, Israel, 2016-2022

Background: Leptospirosis is a bacterial zoonosis with a wide range of presentation, from unspecific and mild symptoms, to a more severe form of disease, which can sometimes be fatal. In Israel, leptospirosis is endemic with occasional outbreaks, including a nationwide outbreak in 2018 of approximately 600 cases. The aim of this study is to describe the epidemiologic, clinical and laboratory characteristics of leptospirosis in the Tel Aviv (TA) District, Israel between 2016-2022. Methods: We retrospectively analyzed all leptospirosis cases among residents of the TA District, Israel, during 2016-2022. Leptospirosis is a notifiable disease by law. An epidemiologic investigation is effectuated for each notified case by a trained nurse. Clinical data were obtained from patients’ clinical files. Results: A total 130 patients with leptospirosis were reported in the TA district between 2016-2022 (rates from 0-7.3 per 100,000 population per year). Most cases were men (n=109, 84%). Hospitalization was required for 40 (31%) cases; no deaths were reported. Among all cases, 78 (60%) were from the Ultra-orthodox city of Bnei Brak, 6 (5%) were workers without legal residency. Common sources of exposure included freshwater recreational activities (85% cases) and exposure to rodents (8% cases) Leptospira serovars were found to be associated with different sources of exposures: L. pomona was associated with exposures to freshwater recreational activities; L. Icterohemorrhagie, L. Sejreo Bratislava and L. Burgas were associated with exposure to rodents. Conclusion: More accessible diagnostic methods should be developed to better recognize the prevalence of leptospirosis and its burden, taking into account clinical symptoms as well as sources of exposures. This should enable adequate treatment and better control of potential reservoirs of leptospirosis and reduce the impact on vulnerable populations, such as residents of areas of lower socio-economic status.