Discovery of Aeromonas hydrophila in sea surface microlayer at Pulau Tenggol, Terengganu

Aeromonas hydrophila is a formidable pathogen that represents a significant threat to both aquatic organisms and human health. To date, research on the abundance of bacterioneuston, particularly A.hydrophila, within the sea surface microlayer remains limited as studies on the sea surface microlayer in Malaysia primarily focus on physicochemical parameters and surfactant concentrations. The presence of A.hydrophila within the sea surface microlayer of Pulau Tenggol’s poses a potential risk for disease transmission to marine fauna, local communities, and visitors. This study was conducted to identify and characterise A.hydrophila isolated from the sea surface microlayer at Pulau Tenggol, Terengganu. The two A.hydrophila isolates identified in this study demonstrated notable pathogenicity, as evidenced by positive reactions in all virulence factor tests and their strong biofilm-forming capabilities. Although A.hydrophila is naturally found in seawater, the relatively low abundance of this pathogen within the sea surface microlayer observed in this study does not constitute an immediate public health concern. Nevertheless, the pathogenic potential of the detected strains and the likelihood of bacterial contamination emphasising the importance of regular monitoring and stringent quality control measures of the sea surface microlayer to mitigate potential risks to the ecosystem and human health.