Dramatic increase in laboratory-diagnosed human cutaneous leishmaniasis cases in southern Israel, 2007-2013

Background: Cutaneous leishmaniasis (CL) is an endemic zoonosis in southern Israel. In recent years, substantial urbanization has been taking place in this region. The introduction of populations into endemic foci was previously reported to facilitate human CL outbreaks. Our aim was to describe a continuous CL outbreak in southern Israel, through laboratory reports of CL diagnosis. Methods: The Soroka University Medical Center parasitology laboratory is the major laboratory confirming CL cases in our region. Data regarding patients referred to the hospital for CL diagnosis were collected retrospectively. Cases were defined by microscopic findings of skin lesion biopsies. Results: The annual number of cases sent for CL laboratory confirmation increased from a mean of 77 +/- 9 in the years 2007-2010 to 178, 327, and 528 in the years 2011, 2012, and 2013, respectively. The respective increase in annual confirmed/positive cases of CL was from 36 +/- 12 to 117, 171, and 282, leading to respective increase in CL rate (per 100 000) from 5.8 +/- 1.9 to 18.4, 26.3, and 42.7. The outbreak was mainly (>60%) observed in the north-west area of the region. Conclusions: In conclusion, a sevenfold increase in laboratory-confirmed CL was observed in southern Israel in 2007-2013, probably reflecting a bigger outbreak, possibly related to urban expansion bordering with CL foci.