Research Commentary: Association of Zoonotic Pathogens with Fresh, Estuarine, and Marine Macroaggregates

• Published in: Microbial ecology 2013-05, Vol.65 (4), p.928-933
• Main Authors: Shapiro, Karen, Miller, Woutrina A., Silver, Mary W., Odagiri, Mitsunori, Largier, John L., Conrad, Patricia A., Mazet, Jonna A. K.
• Format: Article
• Language: English
• Subjects: Aggregates; Aggregation; Animals; Aquatic ecosystems; Bacteria - genetics; Bacteria - isolation & purification; Bacteriophages - genetics; Bacteriophages - isolation & purification; Biological and medical sciences; Biomedical and Life Sciences; Brackish; Brackish water; Cell aggregates; Coastal waters; Cryptosporidium; Ecology; Ecosystem; Electrochemistry; Flocculation; Fluid dynamics; Fresh water; Fresh Water - microbiology; Fresh Water - parasitology; Fresh Water - virology; Freshwater; Freshwater pollution; Fundamental and applied biological sciences. Psychology; Geoecology/Natural Processes; Giardia; Giardia - genetics; Giardia - isolation & purification; Hydrodynamics; Life Sciences; Microbial Ecology; Microbiology; MICROBIOLOGY OF AQUATIC SYSTEMS; Microorganisms; Nature Conservation; Organic matter; Pathogens; Salmonella; Saltwater; Sea water; Seafood; Seawater - microbiology; Seawater - parasitology; Seawater - virology; Water control; Water Microbiology; Water Quality/Water Pollution; Zoonoses; Zoonoses - microbiology; Zoonoses - parasitology; Zoonoses - transmission; Zoonoses - virology
• ISSN: 0095-3628; 1432-184X
• DOI: 10.1007/s00248-012-0147-2

Aquatic macroaggregates (flocs ≥0.5 mm) provide an important mechanism for vertical flux of nutrients and organic matter in aquatic ecosystems, yet their role in the transport and fate of zoonotic pathogens is largely unknown. Terrestrial pathogens that enter coastal waters through contaminated freshwater runoff may be especially prone to flocculation due to fluid dynamics and electrochemical changes that occur where fresh and marine waters mix. In this study, laboratory experiments were conducted to evaluate whether zoonotic pathogens (Cryptosporidium, Giardia, Salmonella) and a virus surrogate (PP7) are associated with aquatic macroaggregates and whether pathogen aggregation is enhanced in saline waters. Targeted microorganisms showed increased association with macroaggregates in estuarine and marine waters, as compared with an ultrapure water control and natural freshwater. Enrichment factor estimations demonstrated that pathogens are 2—4 orders of magnitude more concentrated in aggregates than in the estuarine and marine water surrounding the aggregates. Pathogen incorporation into aquatic macroaggregates may influence their transmission to susceptible hosts through settling and subsequent accumulation in zones where aggregation is greatest, as well as via enhanced uptake by invertebrates that serve as prey for marine animals or as seafood for humans.