Abstract
Despite the active and intense treatment of wastewater, pathogenic microorganisms and viruses are frequently introduced into the aquatic environment. For most human pathogens, however, this is a rather hostile place, where starvation, continuous inactivation, and decay generally occur, rather than successful reproduction. Nevertheless, a great diversity of the pathogenic microorganisms can be detected, in particular, in the surface waters receiving wastewater. Pathogen survival depends majorly on abiotic factors such as irradiation, changes in water ionic strength, temperature, and redox state. In addition, inactivation is enhanced by the biotic interactions in the environment. Although knowledge of the antagonistic biotic interactions has been available since a long time, certain underlying processes and mechanisms still remain unclear. Others are well-appreciated and increasingly are applied to the present research. Our review compiles and discusses the presently known biotic interactions between autochthonous microbes and pathogens introduced into the aquatic environment, including protozoan grazing, virus-induced bacterial cell lysis, antimicrobial substances, and predatory bacteria. An overview is provided on the present knowledge, as well as on the obvious research gaps. Individual processes that appear promising for future applications in the aquatic environment are presented and discussed.
Highlights
Pathogenic microorganisms are frequent visitors, or even inhabitants, of the aquatic environments
Wastewater from households and hospitals undergoes a moderate reduction of pathogens when it is collected and treated in the sewage treatment plants, approximately 1 to 3 orders of magnitude; we know that higher numbers of pathogens are continuously released into the recipient surface waters, in particular in times of increased bacterial and viral infections in the human population (George et al, 2002; Reynolds and Barrett, 2003; Gerba and Smith, 2005; Arnone and Walling, 2007)
From these recipient water bodies, pathogens are distributed into the connected surface waters, Microbial Antagonism in Aquatic Systems such as rivers and lakes, as well as groundwater
Summary
Pathogenic microorganisms are frequent visitors, or even inhabitants, of the aquatic environments. Numerous observations from laboratory experiments and a few field studies have supported the assumption that microbially active soils reduce the amount of introduced pathogenic microorganisms; these studies have a mostly descriptive character, and the specificity as well as the extent of this biotic inactivation is not well-understood (Cutler, 1923; Postma et al, 1990; van Veen et al, 1997) This is, in particular, true regarding the combined action of several antagonistic processes that have received little attention to date. Viruses only marginally contribute to the protozoan diet in terms of carbon (Deng et al, 2014). Hennemuth et al (2008) demonstrated that protozoa may directly reutilize viral amino acids for their own protein biosynthesis
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
