Application of Bacteroides fragilis Phage as an Alternative Indicator of Sewage Pollution in Tampa Bay, Florida

• Published in: Estuaries and coasts Vol. 29; no. 2; pp. 246 - 256
• Main Authors: McLaughlin, Molly R., Rose, Joan B.
• Format: Journal Article
• Language: English
• Published: Heidelberg Estuarine Research Federation 01.04.2006; Springer
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Applied sciences; Bacteriophages; Bacteroides fragilis; Biological and medical sciences; Brackish; Brackish water ecosystems; Coliphages; Environmental pollution; Exact sciences and technology; Fecal coliforms; Fundamental and applied biological sciences. Psychology; Marine; Ocean pollution; Phage B40-8; Pollution; Sea water; Sewage; Sewage effluent; Synecology; Wastewaters; Water pollution; Water treatment and pollution; ASW, USA, Florida, Tampa Bay; USA, Florida, Tampa Bay; Brackish water environment; Bacteroides fragilis; Florida Bay; Estuaries; Biological indicator; Bacteroidaceae; Waste water; Virus; Marine environment; Aquatic environment; Pollution; Bacteria; Tampa Bay; Phage
• ISSN: 1559-2723; 1559-2731
• DOI: 10.1007/BF02781993

Traditional fecal coliform bacterial indicators have been found to be severely limited in determining the significance and sources of fecal contamination in ambient waters of tropical and subtropical regions. The bacteriophages that infect Bacteroides fragilis have been suggested as better fecal indicators and at least one type may be human specific. In this study, the phages that infect B. fragilis host RYC2056 (RYC), including phage B56-3, and host ATCC 51477-HSP40 (HSP), including the human specific phage B40-8, were evaluated in the drainage basins of Tampa Bay, 7 samples (n = 62), or 11%, tested positive for the presence of phages infecting the host HSP, whereas 28 samples, or 45%, tested positive using the host RYC. A survival study was also done to compare the persistence of phages B56-3 and B40-8 to MS2 coliphage in seawater at various temperatures. The decay rates for MS2 were $0.239 log_{10} d^{-1}$ at 10° C, but increased to 0.896 at 20° C and $2.62 log_{10} d^{-1}$ at 30° C. The two B. fragilis phages persisted much longer in the seawater compared to the coliphage and showed little variation between the temperatures. All sewage influents sampled from area wastewater treatment plants contained phages that infected the two B. fragilis hosts at levels from $1.2 \times 10^{-4} to 1.11 \times 10^{5} pfu 100 ml^{-1}$ for host RYC and 67 to 350 pfu $100 ml^{-1}$ for host HSP. Of the 7 chlorinated effluent samples tested, 3 were positive for the presence of the phage using the host RYC and the phage enrichment method, with levels estimated to be $<10 pfu 100 ml^{-1}$. No phages were detected using the host HSP in the treated sewage effluent. Coliphages were found in 3 of the 7 effluent samples at a range of $30 to 1.2 \times 10^{-3} pfu 100 ml^{-1}$.