A global multinational survey of cefotaxime-resistant coliforms in urban wastewater treatment plants

The World Health Organization Global Action Plan recommends integrated surveillance programs as crucial strategies for monitoring antibiotic resistance. Although several national surveillance programs are in place for clinical and veterinary settings, no such schemes exist for monitoring antibiotic-resistant bacteria in the environment. In this transnational study, we developed, validated, and tested a low-cost surveillance and easy to implement approach to evaluate antibiotic resistance in wastewater treatment plants (WWTPs) by targeting cefotaxime-resistant (CTX-R) coliforms as indicators. The rationale for this approach was: i) coliform quantification methods are internationally accepted as indicators of fecal contamination in recreational waters and are therefore routinely applied in analytical labs; ii) CTX-R coliforms are clinically relevant, associated with extended-spectrum β-lactamases (ESBLs), and are rare in pristine environments. We analyzed 57 WWTPs in 22 countries across Europe, Asia, Africa, Australia, and North America. CTX-R coliforms were ubiquitous in raw sewage and their relative abundance varied significantly (<0.1% to 38.3%), being positively correlated (p < 0.001) with regional atmospheric temperatures. Although most WWTPs removed large proportions of CTX-R coliforms, loads over 103 colony-forming units per mL were occasionally observed in final effluents. We demonstrate that CTX-R coliform monitoring is a feasible and affordable approach to assess wastewater antibiotic resistance status

Coping with Temperature at the Warm Edge – Patterns of Thermal Adaptation in the Microbial Eukaryote Paramecium caudatum

Ectothermic organisms are thought to be severely affected by global warming since their physiological performance is directly dependent on temperature. Latitudinal and temporal variations in mean temperatures force ectotherms to adapt to these complex environmental conditions. Studies investigating current patterns of thermal adaptation among populations of different latitudes allow a prediction of the potential impact of prospective increases in environmental temperatures on their fitness.In this study, temperature reaction norms were ascertained among 18 genetically defined, natural clones of the microbial eukaryote Paramecium caudatum. These different clones have been isolated from 12 freshwater habitats along a latitudinal transect in Europe and from 3 tropical habitats (Indonesia). The sensitivity to increasing temperatures was estimated through the analysis of clone specific thermal tolerances and by relating those to current and predicted temperature data of their natural habitats. All investigated European clones seem to be thermal generalists with a broad thermal tolerance and similar optimum temperatures. The weak or missing co-variation of thermal tolerance with latitude does not imply local adaptation to thermal gradients; it rather suggests adaptive phenotypic plasticity among the whole European subpopulation. The tested Indonesian clones appear to be locally adapted to the less variable, tropical temperature regime and show higher tolerance limits, but lower tolerance breadths.Due to the lack of local temperature adaptation within the European subpopulation, P. caudatum genotypes at the most southern edge of their geographic range seem to suffer from the predicted increase in magnitude and frequency of summer heat waves caused by climate change

A global multinational survey of cefotaxime-resistant coliforms in urban wastewater treatment plants

The World Health Organization Global Action Plan recommends integrated surveillance programs as crucial strategies for monitoring antibiotic resistance. Although several national surveillance programs are in place for clinical and veterinary settings, no such schemes exist for monitoring antibiotic-resistant bacteria in the environment. In this transnational study, we developed, validated, and tested a low-cost surveillance and easy to implement approach to evaluate antibiotic resistance in wastewater treatment plants (WWTPs) by targeting cefotaxime-resistant (CTX-R) coliforms as indicators. The rationale for this approach was: i) coliform quantification methods are internationally accepted as indicators of fecal contamination in recreational waters and are therefore routinely applied in analytical labs; ii) CTX-R coliforms are clinically relevant, associated with extended-spectrum ?-lactamases (ESBLs), and are rare in pristine environments. We analyzed 57 WWTPs in 22 countries across Europe, Asia, Africa, Australia, and North America. CTX-R coliforms were ubiquitous in raw sewage and their relative abundance varied significantly (< 0.1% to 38.3%), being positively correlated (p < 0.001) with regional atmospheric temperatures. Although most WWTPs removed large proportions of CTX-R coliforms, loads over 103 colony-forming units per mL were occasionally observed in final effluents. We demonstrate that CTX-R coliform monitoring is a feasible and affordable approach to assess wastewater antibiotic resistance status

Tackling antibiotic resistance: the environmental framework

Antibiotic resistance is a threat to human and animal health worldwide, and key measures are required to reduce the risks posed by antibiotic resistance genes that occur in the environment. These measures include the identification of critical points of control, the development of reliable surveillance and risk assessment procedures, and the implementation of technological solutions that can prevent environmental contamination with antibiotic resistant bacteria and genes. In this Opinion article, we discuss the main knowledge gaps, the future research needs and the policy and management options that should be prioritized to tackle antibiotic resistance in the environment

Isolation of polymorphic microsatellite loci in three phantom midge species of the genus Chaoborus (Diptera : Chaoboridae)

Because of its widespread distribution in lakes and ponds Chaoborus is of great interest to many freshwater ecologists. Interestingly some species are restricted to small fish-less water bodies, whereas other species live mostly in large lakes. To eventually test the genetic and evolutionary implications of these different lifestyles we identified microsatellite loci in three species in this preliminary study: C. obscuripes, C. crystallinus and C. flavicans. Using a biotin/streptavidin capture technique of repetitive sequences in a 96 well format, we obtained microsatellite-enriched genomic libraries for all three species and identified six polymorphic microsatellite markers for each species

Ephemeral metapopulations show high genetic diversity at regional scales

One of the primary questions concerning the long-term preservation of nature and its diversity is the maintenance of genetic diversity. However, despite numerous theoretical investigations, comparative empirical information on how local extinctions influence regional genetic variation does not exist. To our knowledge, this is the first report of an empirical study comparing the genetic variation of permanent vs. ephemeral species at two scales (local variation, regional variation). This approach, utilizing a microsatellite analysis of six midge species of the genus Chaoborus generated intriguing scale-dependent results. Species that experienced repeated local extinctions had reduced genetic variation at the local level, yet the regional genetic variation was greater than in species with permanent populations. Our findings call into question the assumption that species with repeated local extinctions generally contain lower genetic diversity, especially if they experience a nomadic pattern of dispersal. We encourage comparative analyses of empirical genetic data at dual scales as molecular tools become more available in ecological studies. © 2009 by the Ecological Society of America

Appendix B. Data on number of alleles (Na), number of effective alleles (Ne), observed heterozygosity (Ho), expected heterozygostiy (He), and fixation index (F) for each locus for each population and species.

Data on number of alleles (Na), number of effective alleles (Ne), observed heterozygosity (Ho), expected heterozygostiy (He), and fixation index (F) for each locus for each population and species

COST Action ES1403: new and emerging challenges and opportunities in wastewater reuse (NEREUS)

Treated urban wastewater is currently widely reused to compensate for dwindling water supplies, as it is considered to be a reliable alternative water source. In addition, the increasing demand for food due to the expanding world population, both in respect to food security and food safety, and therefore for irrigation water, renders wastewater reuse a practice of utmost importance. As a consequence, sustainable and safe urban water cycles are presently of high priority on the policy agendas of many countries around the world. Although reuse has a number of benefits and major advances have been made with respect to producing treated effluents for reuse (e.g., successful removal of metals, reduction of chemical oxygen demand and of other pollution parameters), several important questions are still unanswered and barriers exist regarding the safety/sustainability of reuse practice. Knowledge gaps associated with wastewater reuse include the following: (a) possible elemental interactions that may influence the accumulation of metals/elements in the soil and their subsequent uptake by plants and crops, (b) the fateof organic microcontaminants in receiving environments, and (c) the epidemiological potential of antibiotic resistant bacteria and/or resistance genes (ARB&ARG) released in the environment via treated effluent. Possible implications on food-chain contamination (biomagnification) require much attention, since treated wastewater is not exempt of such contaminants. The effluents’ residual organic matter after conventional treatment consists of a number of recalcitrant organic compounds including potential endocrine disrupting compounds, many types of pharmaceuticals including antibiotics, disinfection by-products, personal care products, metabolites and transformation products, other organic substances (i.e. pesticides, surfactants, biocides, etc.), and not to be forgotten ARB&ARG. In fact, preliminary results suggest that the relative abundance of certain ARG or ARB may even be enriched during the wastewater treatment (Rizzo et al. 2013). This leads to their subsequent release in the terrestrial and aquatic environments through disposal and reuse applications, and the level of risk to environmental and human health is yet to be evaluated. Contamination of the environment, food chain, drinking water, etc with ARB&ARG is presently considered to be a serious public health problem. For this reason, the World Health Organization (WHO) (WHO 2013) characterized the development of AR as one of the major global threats to society and recommends intensive monitoring for the identification/surveillance of critical hot spots (e.g., wastewater treatment plants), aiming at reducing its propagation. In September 2014, a national strategy (The White House 2014) was announced in the USA by the White House that lays out a series of steps to address the decreasing effectiveness of antibiotics, many being similar to those identified by WHO. According to the European Centre for Disease Prevention and Control, it is estimated that infections caused by a subset of ARB are responsible for about 25,000 deaths in Europe annually. In addition, the extra healthcare costs and productivity losses due to ARB are estimated to reach EUR 1.5 billion (European Centre for Disease Prevention and Control 2013). In the USA, equally dramatic numbers are reported by the Centers for Disease Control and Prevention, with AR infections killing at least 23,000 people and sickening 2 million each year (The White House 2014). All these issues have not received significant attention in the framework of the wastewater reuse practice. The EUCOST Action ES1403 (NEREUS) aims at consolidating the existing scattered data related to wastewater reuse and will address the open challenges associated with it. It will provide the platform for a systematic consolidation of data and standardization of methods for assessing emerging hazards associated with wastewater reuse. The Action is chaired by D. Fatta-Kassinos from Nireas-International Water Research Center and Department of Civil and Environmental Engineering of the University of Cyprus and vice-chaired by C.Manaia from Escola Superior de Biotecnologia, Universidade Católica Portugeusa

Advancing biological hazards risk assessment

This paper focusses on biological hazards at the global level and considers the challenges to risk assessment (RA) from a One Health perspective. Two topics – vector-borne diseases (VBD) and antimicrobial resistance (AMR) – are used to illustrate the challenges ahead and to explore the opportunities that new methodologies such as next-generation sequencing can offer. Globalisation brings complexity and introduces drivers for infectious diseases. Cooperation and the application of an integrated RA approach – one that takes into consideration food farming and production systems including social and environmental factors – are recommended. Also needed are methodologies to identify emerging risks at a global level and propose prevention strategies. AMR is one of the biggest threats to human health in the infectious disease environment. Whereas new genomic typing techniques such as whole genome sequencing (WGS) provide further insights into the mechanisms of spread of resistance, the role of the environment is not fully elucidated, nor is the role of plants as potential vehicles for spread of resistance. Historical trends and recent experience indicate that (re)-emergence and/or further spread of VBD within the EU is a matter of when rather than if. Standardised and validated vector monitoring programs are required to be implemented at an international level for continuous surveillance and assessment of potential threats. There are benefits to using WGS – such as a quicker and better response to outbreaks and additional evidence for source attribution. However, significant challenges need to be addressed, including method standardisation and validation to fully realise these benefits; barriers to data sharing; and establishing epidemiological capacity for cluster triage and response