Microbial water quality of recreational lakes near Tbilisi, Georgia Ekaterine Jaiani, Tamar Kokashvili, Nino Mitaishvili, Tinantin Elbakidze, Nino Janelidze, Nino Lashkhi, Rusudan Kalandadze, Eteri Mikashavidze, Gulnara Natroshvili, Chris A. Whitehouse, Anwar Huq and Marina Tediashvili ABSTRACT Microbial safety of recreational water is one of the major human public health issues in developing countries. Three water bodies, the Tbilisi Sea, Kumisi and Lisi lakes, in the South Caucasus region near Tbilisi, Georgia, were monitored in 2006–2009 to determine microbiological quality using standard methods. Microbial pollution indicators were determined in parallel with phytoplankton abundance and measurement of a number of physical–chemical parameters. Kumisi Lake, a brackish water body in an active agricultural area, appeared to be the most polluted, whereas the Tbilisi Sea, a freshwater reservoir was the least polluted. High values for fecal indicators in all three lakes in summer and early autumn were revealed. In our study, total enterococci counts (TEC) appeared to be a better indicator than either fecal or total coliform counts for the evaluation of fresh and brackish microbial water quality. We found significant correlation between total Vibrio counts and TEC for all three water bodies. Prevalence of somatic coliphages and V. cholerae-specific phages as additional water pollution indicator significantly correlated with abundance of the host bacteria. Particular phytoplankton groups in the lakes responded to the changes of fecal indicators; however, no correlation was observed between dominant zooplankton taxonomic groups and microbial parameters. Ekaterine Jaiani Tamar Kokashvili Nino Mitaishvili Tinantin Elbakidze Nino Janelidze Nino Lashkhi Gulnara Natroshvili Marina Tediashvili (corresponding author) George Eliava Institute of Bacteriophage, Microbiology and Virology, Tbilisi 0160, Georgia E-mail: m_tediash.ibmv@caucasus.net Rusudan Kalandadze Eteri Mikashavidze Black Sea Monitoring Institute, The National Environmental Agency of Georgia, Batumi 6010, Georgia Chris A. Whitehouse United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, MD 21702-5011, USA Anwar Huq Maryland Pathogen Research Institute, University of Maryland, College Park, Bioscience Research Building # 413, Room 3132, MD 20742, USA Key words | fecal indicators, phages, phytoplankton, recreational waters, vibrios, water quality INTRODUCTION Microbial contamination of aquatic ecosystems is a major public health concern in both developing and developed countries. Pathogen composition in a particular location may vary depending on the type, nature (e.g., lake, estuary), and microbial profile of effluents from surrounding areas. In waters used for recreation, organisms of concern include Salmonella spp., Shigella spp., Vibrio spp., Escherichia coli, Clostridium spp., and various human enteric viruses and protozoa (Golubovskaya ; Fleisher et al. ; Wade et al. ; Fong & Lipp ). In general, the most significant threats are autochthonous microorganisms that may be triggered to multiply when conditions are favorable. In addition, reservoirs often are contaminated through external loading, e.g., runoff from agricultural and/or urban catchments via rain waters or direct discharge of efflu- ents from farms. Enteric coliform bacteria (e.g., total coliforms or fecal coliforms), as well as E. coli and entero- cocci are the most widely used indicators of water microbial pollution (US EPA ; APHA ; WHO ; Wheeler et al. ). Total vibrios, including V. cho- lerae, can be considered as model organisms for the abundance of autochthonous flora, and their abundance 333 © IWA Publishing 2013 Journal of Water and Health | 11.2 | 2013 doi: 10.2166/wh.2013.057 Downloaded from https://iwaponline.com/jwh/article-pdf/11/2/333/395504/333.pdf by guest on 15 December 2018