Two-Year Monitoring of Water Samples from Dam of Iskar and the Black Sea, Bulgaria, by Molecular Analysis: Focus on Mycobacterium spp.

Stefan Panaiotov,Emilio D'Ugo,Bas Boots,Karim Helmi,Pauline Jacob,Ivan Simeonovski,Todor Kantardjiev,Ulrich Breitenbach,Victoria Levterova,Nadia Brankova,Laura Mancini,Ventzislav Karamfilov,Stefania Marcheggiani,Erik Mielke,Kristin Tankova,Katrina Campbell

doi:10.3390/ijerph120707430

Stefan Panaiotov, Emilio D'Ugo + Show 14 more

Open Access

PDF Available

https://doi.org/10.3390/ijerph120707430

Copy DOI

Export

Save

Cite

Abstract
Highlights/Summary
Full-Text PDF
Similar Papers

Abstract

Listen

The coast of the Bulgarian Black Sea is a popular summer holiday destination. The Dam of Iskar is the largest artificial dam in Bulgaria, with a capacity of 675 million m3. It is the main source of tap water for the capital Sofia and for irrigating the surrounding valley. There is a close relationship between the quality of aquatic ecosystems and human health as many infections are waterborne. Rapid molecular methods for the analysis of highly pathogenic bacteria have been developed for monitoring quality. Mycobacterial species can be isolated from waste, surface, recreational, ground and tap waters and human pathogenicity of nontuberculose mycobacteria (NTM) is well recognized. The objective of our study was to perform molecular analysis for key-pathogens, with a focus on mycobacteria, in water samples collected from the Black Sea and the Dam of Iskar. In a two year period, 38 water samples were collected—24 from the Dam of Iskar and 14 from the Black Sea coastal zone. Fifty liter water samples were concentrated by ultrafiltration. Molecular analysis for 15 pathogens, including all species of genus Mycobacterium was performed. Our results showed presence of Vibrio spp. in the Black Sea. Rotavirus A was also identified in four samples from the Dam of Iskar. Toxigenic Escherichia coli was present in both locations, based on markers for stx1 and stx2 genes. No detectable amounts of Cryptosporidium were detected in either location using immunomagnetic separation and fluorescence microscopy. Furthermore, mass spectrometry analyses did not detect key cyanobacterial toxins. On the basis of the results obtained we can conclude that for the period 2012–2014 no Mycobacterium species were present in the water samples. During the study period no cases of waterborne infections were reported.

Highlights

During the last two decades waterborne infections have contributed to the emergence of illnesses in Bulgaria, such as Q-fever and tularemia, which were previously rare or unknown [1,2,3]
We focused on the application of rapid molecular tests based on the use of PCR and Real-Time PCR for detection of the key-pathogens Mycobacterium spp., Vibirio spp., Listeria monocytogenes, Clostridium perfringens, Clostridium botulinum, Shigella spp., Salmonella spp., and Yersinia enterocolitica
Microscopic and PCR analyses demonstrated that no mycobacterial were present in the water samples (Table 1)

Summary

Introduction

During the last two decades waterborne infections have contributed to the emergence of illnesses in Bulgaria, such as Q-fever and tularemia, which were previously rare or unknown [1,2,3]. Studies have confirmed that the sources of infections originated from the drinking water supply system. Contamination of water sources often occurs by accidental falls of animals into water reservoirs or contamination by fecal matter linked to agricultural activities. Black Sea marine coastal zone, especially in sea resorts, is a serious ecological and public health concern. The Bulgarian Black Sea shore is a popular recreational and vacation destination for tourists. The Dam of Iskar, with a capacity of 675 million m3, is part of the largest artificial lake in Bulgaria, and a popular place for aquatic leisure activities. The Dam of Iskar is the main source of tap water for the capital

Objectives

Results

Conclusion