Detection of Emergent and Opportunistic Pathogens in the San Juan Bay Estuary system in Puerto Rico
Citation:
Hanlon, J., M. Molina, S. Brown, I. Cappielo Cosme, B. Parker, AND M. Cuebas Irizarry. Detection of Emergent and Opportunistic Pathogens in the San Juan Bay Estuary system in Puerto Rico. 2024 American Society for Microbiology Annual Meeting, Atlanta, GA, June 13 - 17, 2024.
Impact/Purpose:
Due to the rapid rate of urbanization, some communities across the San Juan Bay Estuary (SJBE) have limited access to or are impacted by failures in the wastewater infrastructure. Those failures, paired with flooding events, can lead to contamination of the SJBE, posing a public health risk in an area heavily used for recreational activities. In this study, we characterize the bacterial communities across the estuarine system using NGS and will identify through qPCR analysis the presence of emergent or opportunistic pathogens. This study will elucidate the effect of environmental factors, including land use, on bacterial community composition and the impact of anthropogenic stressors on the abundance of pathogenic bacteria across a tropical estuary.
Description:
The San Juan Bay Estuary (SJBE) is an interconnected system of streams, bays, lagoons, and canals located in a highly urbanized area in San Juan, Puerto Rico. Due to the rapid rate of urbanization, some communities across the SJBE have limited access to or are impacted by failures in the wastewater infrastructure. Those failures, paired with flooding events, can lead to contamination of the SJBE, posing a public health risk in an area heavily used for recreational activities. In this study, we aim to: (I) Characterize the bacterial communities across the estuarine system with emphasis on the presence of emergent or opportunistic pathogens; and (II) Identify factors that influence the presence of these pathogens in specific areas of the estuary. Water samples were collected from 16 sites throughout the estuary during the wet (June-November) and dry (December – May) seasons from May 2021 thru December 2023 and filtered through 0.45 um filters. DNA was extracted from each filter for 16s rRNA amplicon-based sequencing using an Illumina MiSeq. Fastq files were processed using QIIME2 for taxonomy assignment. NMDS analysis indicated that location in the estuary significantly influenced the composition of the bacterial community, with samples collected at the bay, canals, and lagoons forming distinct clusters from each other. Taxonomic groups containing potential emergent pathogens (Aeromonas spp, Arcobacter spp) and waterborne pathogens (Vibrio spp and Campylobacter spp.) were identified in the western part of the estuary and correlated with the presence of stormwater outfalls combined with inputs of untreated wastewater. In contrast, none of these taxa were detected in the system with the least urbanization and with the highest mangrove coverage (Pinones Lagoon). Similar microbial community composition was observed in both wet and dry seasons, with the exception that members of the Vibrio family were only detected during the wet season. Further analyses will elucidate the effect of environmental factors, including land use, on bacterial community composition and the abundance of pathogenic bacteria across the estuary.