Outbreak of acute fasciolosis in sheep farms in a Mediterranean area arising as a possible consequence of climate change.

The objective of the present study was to investigate whether climate change in recent years have influenced the onset of acute outbreaks of Fasciola hepatica in ovine farms in southern Italy. In May-June 2014, a severe outbreak of F. hepatica occurred in three sheep farms in the Campania region. Clinical, coprological and necroscopic examinations were performed. Morbidity and mortality due to F. hepatica were 3-67% and 3-50%, respectively. Coprological examinations showed high values of F. hepatica eggs per gram (EPG) of faeces (860-1,240). Similarly, high adult parasitic burdens were found in animals that had sucombed (124-426 flukes). The study area was georeferenced and climatic data (temperature, humidity, days of rain and total amount of rainfall) were recorded at four georeferenced meterological stations in the study area. Montly data were processed and analyzed for the period 2000-2013 to evaluate the change of the climatic parameters during these years. The results show that there was a significant increase (P<0.001) of temperature, increased rainfall and increase in the number of rainy days compared to previous years. In addition to the outbreak reported here, we discuss the potential effects of climate change on the epidemiology of F. hepatica and the implications for sheep farming in the Mediterranean area.