Epidemiology of jellyfish stings using the Sting Index to identify trends and support proactive management

Abstract

We explore the epidemiological trends of jellyfish stings along the south and eastern Spanish coast. Using data from lifeguard reports over a 15-year span, we offer a comprehensive analysis of the “Sting Index” (SI), initially described by Bordehore et al. (2016). Our findings reveal that from 2008 to 2022, jellyfish stings accounted for 54.5% of reported beach injuries, a slight decrease from the previously reported 59.7% in 2012. We found 359,909 people were stung during the study period from 787 participating lifeguard stations. We observed high variability in the SI, with a peak in 2012, followed by a period of stability with a slight decrease overall from 2013 onwards. However, the number of stings did not see the same decrease. The Balearic Islands and Granada exhibit the highest SI. Despite visual overlaps in their distribution, we found no significant correlation between SI and sightings of high-stinging species like Pelagia noctiluca. The knowledge derived from our research is vital for developing informed beach management policies, improving beachgoer safety, and monitoring jellyfish presence. By providing a more accurate reflection of sting incidents through the SI, independent of fluctuations in beach attendance, this study enhances our understanding of jellyfish impacts and aids in the implementation of effective management measures.