Urbanization and Waterborne Pathogen Emergence in Low-Income Countries: Where and How to Conduct Surveys?

Abstract

A major forthcoming sanitary issue concerns the apparition and spreading of drug-resistant microorganisms, potentially threatening millions of humans. In low-income countries, polluted urban runoff and open sewage channels are major sources of microbes. These microbes join natural microbial communities in aquatic ecosystems already impacted by various chemicals, including antibiotics. These composite microbial communities must adapt to survive in such hostile conditions, sometimes promoting the selection of antibiotic-resistant microbial strains by gene transfer. The low probability of exchanges between planktonic microorganisms within the water column may be significantly improved if their contact was facilitated by particular meeting places. This could be specifically the case within biofilms that develop on the surface of the myriads of floating macroplastics increasingly polluting urban tropical surface waters. Moreover, as uncultivable bacterial strains could be involved, analyses of the microbial communities in their whole have to be performed. This means that new-omic technologies must be routinely implemented in low- and middle-income countries to detect the appearance of resistance genes in microbial ecosystems, especially when considering the new ‘plastic context.’ We summarize the related current knowledge in this short review paper to anticipate new strategies for monitoring and surveying microbial communities.

Vibrio Colonization Is Highly Dynamic in Early Microplastic-Associated Biofilms as Well as on Field-Collected Microplastics

“…While in most regions of the world’s oceans we do not expect a relevant colonization of microplastics with potentially pathogenic taxa, the risk might be higher in strongly anthropologically impacted areas. A great amount of plastic waste worldwide enters the oceans at coastal sites with high populations, often situated at estuaries with dynamic conditions, and close to waste water drainage systems, such that an enhanced dissemination of potentially pathogenic bacteria on plastics poses a realistic threat to these communities [ 52 ].…”

High‐throughput molecular analyses of microbiomes as a tool to monitor the wellbeing of aquatic environments

“…The prevalence and dissemination of antimicrobial resistance (AMR) is an increasingly serious threat to global public health (WHO, 2015;Qiao et al, 2018;Thomas et al, 2020), that has turned into an emergency in lowincome countries (Bastaraud et al, 2020). Consequently, a significant reduction in the effectiveness of antibiotics and other antimicrobial agents (antifungals, antivirals, antimalarials, and anthelmintics) threatens our ability to treat common infectious diseases, resulting in prolonged illness, disability, and death (Wright, 2010;Almakki et al, 2019).…”

“…Recently, flow cytometry and 16S rRNA sequencing have shown that silver nanoparticles (AgNPs) clearly affect the microbial community structure and suggest a potential negative impact on WWTP functions (Guo et al, 2019). Finally, given the increased presence of microplastics as aquatic emerging water pollutants, their role as potential vectors for harmful microbes and propagation of ARBs and ARGs is a matter of growing concern (Bastaraud et al, 2020;Song et al, 2020;Zhang et al, 2020).…”

<em> </em>Current Research on Microbe-Plastic Interactions in the Marine Environment

“…(i) use multi-OMIC and interdisciplinary approaches to understand the role of the plastisphere in plastic biodegradation as well as in determining the mechanisms and pathways used for biodegradation 19,151,157,161,164,170,172,175,178,180,181,183,184,188,189,191,194,196,[198][199][200][204][205][206][207] ;…”

“…Other taxa that are not generally regarded as invasive, toxic or pathogenic as such, but that can cause nuisance via mucilage events, such as the diatom species Ceratoneis closterium 83 have also been reported as plastisphere members. Alongside the potential toxicity of the plastic polymer itself, or plastic additives and sorbed contaminants (as reviewed recently by Pham et al 207 ), plastics' potential to be considered harmful clearly also depends on the interaction with pathogens and non-native taxa present in the environment (see above), especially in polluted environments such as wastewater effluents and water bodies in the proximity of densely populated urbanised areas 180 .…”