Predicting the Global Distribution of Vibrio vulnificus Under Changing Climate Scenarios

Vibrio vulnificus is a Gram-negative bacterium and an emerging pathogen globally distributed in brackish and marine waters. It can be transmitted to humans through contaminated food, which causes primary septicemia, or through wound exposure, causing necrotizing fasciitis. Increased abundance and range expansion have recently been associated with climate change. Further understanding of the spatial epidemiology of V. vulnificus is necessary, and species distribution modeling is a technique to correlate all the factors related to the spread of V. vulnificus. Through meta-analysis aided by Rayyan, extraction of environmental variables from Bio-ORACLE, and global mapping using QGIS and MaxEnt, a global model of V. vulnificus suitability is projected under current and future climate scenarios. The model indicates that sea surface minimum chlorophyll-a, mean dissolved oxygen, mean pH, and mean salinity are good predictors of V. vulnificus occurrence, with minimum chlorophyll-a and mean salinity having the greatest percent contribution at 53.3 and 31.6, respectively. Specific geographic locations with moderate to high V. vulnificus suitability include the west coast of Colombia, the coast of Uruguay, the northeastern coast of Brazil, the coast of Maryland and Louisiana, USA, the coast of China, the Black Sea, the south coast of South Africa, and the coast of Poland and Lithuania. A northward shift in V. vulnificus populations is observed due to climate change driven by plankton migration and decreasing salinity. These findings highlight the potential of these suitability maps for future V. vulnificus surveillance, and disease protection and control.