ABSTRACT
Waterborne pathogens and associated diseases continue to pose a significant global health challenge, requiring effective monitoring, detection, and treatment strategies. This review examines the current state of waterborne pathogen management, highlighting persistent issues and recent advancements. Here, we review cutting-edge detection methods and treatment technology, emphasizing their roles in water safety and outbreak prevention. The impact of climate change on waterborne pathogen dynamics is explored, alongside a discussion of interdisciplinary research approaches. We also aimed to investigate the crucial relationship between waterborne disease control and Sustainable Development Goals (SDGs), focusing on community engagement, well-being, water sanitation, public health policies, and international cooperation. The PRISMA protocol systematic process was used to filter papers for this study and carry out the review process. Machine learning and remote sensing techniques are promising features in the pathogen detection field. SDGs 3, 6, 11, 13, and 17 are the most closely interrelated with waterborne diseases. This review provides an in-depth overview of waterborne pathogen management, contributing to improved global water quality and public health strategies. This integrated approach aims to enhance health outcomes and promote resilience against waterborne diseases, particularly for vulnerable communities.
HIGHLIGHTS
The influence of climate change on waterborne diseases should not be disregarded.
Sustainable Development Goals No 3, 6, 11, 13, and 17 are closely related to waterborne diseases.
Interdisciplinary research frameworks and collaboration with policymakers are urgently needed.
ABBREVIATIONS
- WBDs
waterborne diseases
- WHO
World Health Organization
- RNA
ribonucleic acid
- SDGs
Sustainable Development Goals
- VOS
visualization of similarities
- qPCR
quantitative polymerase chain reaction
- q(RT)-PCR
quantitative reverse transcription polymerase chain reaction
- AOPs
advanced oxidation processes
- CP
cold plasma
- PCR
polymerase chain reaction
- DNA
deoxyribonucleic acid
- NGS
next-generation sequencing
- WPPs
waterborne protozoan parasites
- ASSURED
affordable, sensitive, specific, user-friendly, rapid and robust, equipment-free, deliverable to end-users
- AI
artificial intelligence
- TiO2
titanium oxide
- Au
gold
- Ag
silver
- MST
microbial source-tracking
- FISH
fluorescence in situ hybridization
- GIS
geographic information systems
- ROS
reactive oxygen species
- UV
ultraviolet
- MF
microfiltration
- UF
ultrafiltration
- NF
nano filtration
- RO
reverse osmosis
- BioDWT
biological drinking water treatment
- DPSEEA
driving force-pressure-state-exposure-effect-action
- PSR
pressure-state-response
- DPSIR
driving force-pressure-state-impact-response
- EPIS
exploration, preparation, implementation, sustainment
- WPM
waterborne passenger mobility
- WASH
water, sanitation, and hygiene
INTRODUCTION
Water is essential for sustaining life on Earth, playing a crucial role in human activities, economic growth, social welfare, and basic necessities such as food and healthcare. However, ongoing development and industrial growth threaten the purity of our water sources with various contaminants, both biological and non-biological. Among these, waterborne pathogens have emerged as a significant global health issue. These pathogens are found in diverse aquatic environments, from freshwater ecosystems like rivers and lakes to marine habitats and domestic water supplies (Mishra 2023). The burden of waterborne diseases (WBDs) is substantial and widespread. The World Health Organization (WHO) estimates that these diseases cause approximately 2.4 million deaths annually. The economic impact is equally alarming, with costs amounting to about 1 billion dollars annually in the United States alone (Ingerson-Mahar & Reid 2013) and a global economic cost approaching 12 billion US dollars (Alhamlan et al. 2015). These diseases are caused by a diverse array of infectious agents, including bacteria, viruses, protozoa, and parasites. They are transmitted primarily by ingestion or contact with contaminated water and may lead to various health issues such as gastrointestinal disorders.
Notably, waterborne infections remain a major obstacle in realizing these ambitious objectives. The complexity of waterborne pathogens introduces multifaceted biological challenges to researchers, requiring in-depth knowledge of microbiology, biochemistry, and genetics, as well as advanced technological tools. The rapid mutation and genetic diversity of these pathogens, particularly ribonucleic acid (RNA) viruses, present a constantly shifting target for researchers. This dynamic nature requires continuous adaptability and innovation in the development of effective diagnoses, treatments, and vaccines. These challenges test our ability to combat these waterborne threats effectively (Mohanty et al. 2023). Furthermore, environmental dynamics add another layer of complexity to addressing WBDs. Pathogen behavior can be significantly influenced by factors such as water quality, temperature, and interactions with other microorganisms (Dean & Mitchell 2022). Accurately reproducing these dynamic environmental conditions in laboratory settings presents a critical challenge in bridging the gap between controlled research environments and actual field conditions.
This review navigates the complexities of waterborne disease research, emphasizing the need to strengthen the relationship between laboratory research and on-the-ground management and prevention measures. We advocate for a multidisciplinary approach, integrating microbiology, biochemistry, epidemiology, environmental science, and public health. However, this integration presents its own challenges, including differences in communication styles and research approaches across disciplines. Overcoming these interdisciplinary barriers is crucial for developing a more integrated and effective strategy against waterborne diseases, ultimately leading to improved health outcomes.
Building on these insights, this review pursues two primary objectives: (1) to provide a framework for advancing the complex landscape of waterborne disease research through an interdisciplinary approach and (2) to highlight the interrelationship between this research and the Sustainable Development Goals (SDGs), seeking to create a synergy between waterborne disease research and global sustainability development efforts.
METHODOLOGY
Data mining and extraction
Our initial search was conducted using the Web of Science database, with further searches performed through PubMed, Science Direct, and Google Scholar to ensure comprehensive coverage. Our aim was to navigate the WBDs research together and connect it with interdisciplinary studies and sustainability direction. Most of the references used in this paper were published within the last 5 years and represent the most up-to-date knowledge regarding waterborne pathogens. We applied objective inclusion criteria at each stage of screening to establish a dataset that reflects current trends and challenges in waterborne disease research and pathogen detection, ensuring alignment with both interdisciplinary frameworks and sustainability goals (Supplementary Table S1). This approach was designed to minimize potential selection bias and provide a balanced and comprehensive foundation for our analysis.
Description of the systematic process phases used to filter papers for this study in the form of a PRISMA flowchart (Page et al. 2021).
Description of the systematic process phases used to filter papers for this study in the form of a PRISMA flowchart (Page et al. 2021).
Keywords and co-occurrence analysis
(Left panel) Linkage of keywords obtained from 121 research papers with co-occurrence analysis of WBDs and SDGs in the Web of Science database (created by VOS viewer version 1.6.20). (Right panel) Cloud map of keywords about the study with a size different depending on the cruciality.
(Left panel) Linkage of keywords obtained from 121 research papers with co-occurrence analysis of WBDs and SDGs in the Web of Science database (created by VOS viewer version 1.6.20). (Right panel) Cloud map of keywords about the study with a size different depending on the cruciality.
The co-occurrence analysis from the Web of Science shows five main clusters with five distinct colors (Figure 2, left panel). The blue (waterborne disease) and red (SDGs) clusters are very crucial and interrelated with each other. The keywords that appeared most were ‘sustainable development goals’ (total link strength 1,122), ‘challenges’ (total link strength 252), and ‘waterborne disease’ (total link strength 80), which had strong links to the study title. The main keywords were ‘health’ (total link strength 209), ‘impact’ (total link strength 241), and ‘quality’ (total link strength 128) for these two clusters. Yellow cluster words (interdisciplinary) are mainly correlated and combined with words in the red cluster. The importance of the literature search for this specific topic can be seen within the figure, and it is clearly shown that it is very complex to navigate the WBDs research and link with other vital topics. The word cloud map related to this specific topic is shown in Figure 2, right panel and this shows the important keywords with different sizes depending on the word's vitality. Sustainability, health, pathogens, WBDs, interdisciplinary, and challenges are the main keywords in the cloud map as well as in the literature search throughout the process of the study.
RESULTS AND DISCUSSION
Waterborne pathogens
Uncontrolled wastewater disposal has transformed numerous water sources into reservoirs of human and animal waste, facilitating the proliferation of pathogens associated with various WBDs. This critical situation is further intensified by climate change, rapid population shifts, and the alarming emergence of antibiotic-resistant bacteria. Addressing these multifaceted challenges demands urgent action, including the implementation of robust water monitoring systems, advanced disinfection methods, and proactive management practices (Magana-Arachchi & Wanigatunge 2020). The continued prevalence of unregulated wastewater disposal creates an environment conducive for pathogens to adapt, potentially becoming more virulent, resilient, and antibiotic-resistant (Bastaraud et al. 2020). The complex issue of water contamination from diverse fecal sources underscores the need for sophisticated predictive models that focus on pathogen behavior and survival mechanisms (Alegbeleye & Sant'Ana 2020). To devise effective management strategies, a thorough understanding of the microbial ecology in the surface water is essential (Jin et al. 2018b). Recent technological advancements have introduced rapid on-site detection methods such as paper-based assays (e.g., for Escherichia coli detection) (Gunda et al. 2017), microfluidic platforms (used in the detection of Listeria monocytogenes, E. coli, and Salmonella) (Altintas et al. 2018), and lateral flow devices (employed for detecting Pseudomonas aeruginosa toxin genes) (Jin et al. 2018a) while the utilization of biological indicators, such as E. coli and advanced microarray techniques, has significantly enhanced risk assessment capabilities. These innovations have enabled more timely and proactive interventions in water management (Kumar et al. 2019). These developments represent crucial steps forward in the ongoing battle against waterborne pathogens and their associated diseases, opening up promising avenues for enhancing water safety and improving public health outcomes.
Viruses
Waterborne viruses are a significant global health threat due to their persistence, ease of transmission, and low infectious dose (Song et al. 2023). These pathogens contaminate water sources and cause a wide range of illnesses, from mild gastroenteritis to severe hepatitis and neurological disorders. Notable examples include adenovirus (respiratory and gastrointestinal infections), astrovirus (gastroenteritis), hepatitis A and E (liver diseases), rotavirus and norovirus (severe gastroenteritis), and various enteroviruses (diverse conditions including meningitis and myocarditis) (Zhang et al. 2022b).
Inadequately treated wastewater remains a major concern in the fight against waterborne viruses, with contamination risks persisting throughout drinking water distribution systems (Chen et al. 2021). Even when wastewater treatment plants successfully remove bacteria such as E. coli, significant amounts of harmful enteric viruses, such as noroviruses, can remain in treated wastewater effluent. This issue is exacerbated by environmental factors that contribute to viral spread. Urban groundwater, another crucial drinking water source, faces growing contamination risks due to ageing infrastructure, inadequate wastewater management, and the increasing frequency of climate change-induced natural disasters (Rusiñol 2023). Flooding events, in particular, can exacerbate the spread of viruses in groundwater (Masciopinto et al. 2019).
Understanding viral behavior in aquatic environments is crucial for developing effective strategies. Viruses can form clusters that enhance their survival and resistance to disinfection methods. Their interactions with bacteria can also influence transmission, further complicating control efforts (Zhang et al. 2022b). This complexity is particularly evident in settings like hospital wastewater, where a diverse range of viral types may be present (Ghernaout et al. 2020).
To tackle these challenges, researchers are investigating various approaches. Coliphages, viruses that infect bacteria, can serve as indicators to assess viral pathogens' removal efficiency in wastewater treatment (Simhon et al. 2019). Wastewater epidemiology, which analyzes the presence of various waterborne viruses in wastewater and feces, offers a proactive approach for detecting potential outbreaks before they occur (Xagoraraki & O'Brien 2020).
Advancements in detection methods are also crucial. While quantitative polymerase chain reaction is a powerful tool for viral detection, it has limitations in determining infectivity. Capsid integrity quantitative reverse transcription polymerase chain reaction (q(RT)-PCR) offers a solution by providing a way to assess potential infectivity and gain a more accurate understanding of viral threats (Canh et al. 2022). Moreover, innovative disinfection technologies, such as advanced oxidation processes (AOPs) and cold plasma, show promise as eco-friendly tools for reducing viral spread in water (Filipić et al. 2020; Kokkinos et al. 2021). Nanoparticle-enhanced methods are also being developed to improve monitoring capabilities for waterborne viruses (Ghernaout et al. 2020). However, challenges remain. The small size of viruses and filtration limitations make detecting infectious viruses difficult, likely contributing to the underreporting of waterborne illnesses (Ramírez-Castillo et al. 2015). To enhance water safety, it is imperative to prioritize the removal of pathogenic viruses like adenovirus and norovirus in water treatment evaluations. Ongoing research and development in viral detection, removal, and inactivation methods are essential for effectively combating the threat of waterborne viruses and ensuring safer water supplies for communities worldwide.
Bacteria
Waterborne bacterial pathogens pose a significant health threat, making the immediate and reliable detection of these organisms in water sources imperative for ensuring public safety (Deshmukh et al., 2016; Yarima & Yarima 2018). The challenge of bacterial detection is multifaceted, requiring methods that are fast, accurate, and easy to use, especially in resource-limited settings (Canciu et al. 2021). Climate change and contaminated irrigation water increase the risk of both waterborne and foodborne bacterial outbreaks, particularly affecting fresh produce (Bell et al. 2021). This evolving threat landscape necessitates the development of rapid, on-site detection technologies to combat outbreaks effectively (Bell et al. 2021; Petrucci et al. 2021).
While traditional methods for detecting waterborne and foodborne bacteria, such as culturing and PCR, are still widely used, they often lack the speed required for immediate response (Canciu et al. 2021). The advancement of molecular techniques, exemplified by PCR and deoxyribonucleic acid (DNA) microarrays, has undeniably enhanced the speed and accuracy of microbial analysis (Alhamlan et al. 2015). The emergence of next-generation sequencing (NGS) further amplifies this progress, offering unprecedented potential for comprehensive microbial profiling, particularly in aquatic environments. The high-throughput nature of NGS, coupled with its capacity for generating extensive sequence data, enables in-depth characterization of microbial communities, surpassing the limitations of traditional culture-based methods (Zhao et al. 2023). However, it is crucial to acknowledge that current NGS workflows may involve time-consuming laboratory procedures and complex data analysis, which can limit their applicability for rapid, on-site assessments (Zhang et al. 2021). Additionally, careful consideration of library preparation methods and primer choice is essential to ensure accurate and comprehensive microbial profiling, particularly when differentiating between closely related strains with varying pathogenicity (Alhamlan et al. 2015).
The rise of antibiotic-resistant bacteria adds another layer of complexity to the detection challenge. Rapid and accurate identification, such as optical technologies of resistant strains, is crucial for effective treatment and containment strategies (Locke et al. 2020). Wastewater surveillance, critical for monitoring both waterborne and foodborne pathogens, such as E. coli and Salmonella, requires improved pathogen recovery methods to overcome the challenges posed by complex wastewater systems (Zhang et al. 2021). Future research should focus on developing detection methods that combine high sensitivity, rapid results, and cost-effectiveness with the ability to identify multiple bacterial species, including antibiotic-resistant strains. These advancements, coupled with the integration of portable, user-friendly devices and real-time data analysis systems, will be crucial for swift identification and response to bacterial contamination, thereby significantly enhancing water safety and public health protection worldwide.
Protozoa
Waterborne protozoa pose a significant global health risk, with Giardia and Cryptosporidium responsible for most outbreaks (Ma et al. 2022). However, the full range of waterborne protozoan parasites (WPPs) extends beyond these well-known pathogens, including emerging threats such as Cyclospora, Toxoplasma, Entameba histolytica, Naegleria fowleri, and Acanthamoeba spp. (Risebro et al., 2007; Zerbo et al. (2021); Plutzer & Karanis, 2016; Triviño-Valencia et al., 2016; Moreno et al. 2018).
Climate change, particularly drought, intensifies the transmission of waterborne protozoan diseases through increased contact between wild animals and humans and a growing reliance on less-treated water sources (Angelici & Karanis 2019; Nemati et al. 2023). This environmental shift underscores the need for robust surveillance and prevention strategies, even in developed countries where outbreaks still occur.
Detection and monitoring of WPPs present significant challenges. While standardized protocols exist, they often focus on Giardia and Cryptosporidium, potentially overlooking other harmful protozoa (Palos Ladeiro et al. 2013). Traditional detection methods have limitations in sensitivity and specificity, but advancements in molecular techniques and point-of-care diagnostics offer promise for improved detection and disease surveillance (Rosado-García et al. 2017; Nemati et al. 2023). Innovative approaches, such as using aquatic invertebrates as biomonitors due to their filtering activity, show potential for monitoring protozoa contamination. However, this method's reliability may be affected by the complex relationship between protozoa accumulation and the health of these indicator organisms.
Current advances in pathogen detection
Illustration of the waterborne pathogen detection and disease occurrence caused by bacteria (adapted from Jung et al. 2023).
Illustration of the waterborne pathogen detection and disease occurrence caused by bacteria (adapted from Jung et al. 2023).
Various methods for pathogen detection exist, with molecular and nanotechnology-based approaches being the most common (Figure 3). Molecular methods appear particularly well-suited for health risk assessment research (Ramírez-Castillo et al. 2015). Emerging technologies, such as artificial intelligence (AI), machine learning, and remote sensing, show promise but are still in development stages and thus less frequently used.
Nanotechnology-based methods
Nanotechnology has emerged as an innovative and effective approach for filtration, detection, and treatment of WBDs. While recent assessments have primarily focused on foodborne pathogens, the application of nanotechnology to waterborne pathogen detection is gaining momentum (Hauck et al. 2010; Kaittanis et al. 2010; Bridle et al. 2015). Advanced nanofilters utilizing nanoparticles have demonstrated exceptional efficacy in removing pathogens from water due to their minute dimensions, effectively impeding the passage of bacteria and viruses (Shanker et al. 2020; Gacem & Wink 2021). Furthermore, the development of nanosensor technology, capable of detecting infections at extremely low concentrations, marks a significant advancement in early disease detection and water purification methods (Bridle 2021; Reddy et al. 2022).
Recent research has increasingly focused on applying nanomaterials specifically to waterborne pathogen detection (Bhardwaj et al. 2019; Ojha 2020). Various nanomaterials play crucial roles in these applications. Quantum dots, titanium oxide (TiO2), gold (Au), silver (Ag), metal oxides, and carbon-based materials functionalized with biomarkers are commonly used for pathogen detection. These materials contribute significantly to waterborne pathogen assessments and monitoring, which are essential for epidemic prevention policies (Kokkinos et al. 2020; Reddy et al. 2022).
Despite its growing popularity, nanotechnology faces several challenges in the context of waterborne pathogen detection. These include concerns about the long-term safety and environmental impacts of nanomaterials, cost-efficiency issues, and the feasibility of large-scale implementation, particularly in resource-constrained settings (Bridle 2021; Reddy et al. 2022). Additionally, regulations governing the safe and responsible use of nanotechnology in this field are still evolving. Nevertheless, this targeted approach, coupled with continuous innovations in the field, holds promise for improving our ability to detect and manage waterborne pathogens effectively.
Molecular methods
Molecular methods have revolutionized the identification and analysis of water pathogens, offering fast, sensitive, and accurate diagnostic techniques essential for public health actions. These methods are employed to assess water's microbiological characteristics, evaluate pathogen removal effectiveness in treatment facilities, and serve as microbial source-tracking tools (Girones et al. 2010).
PCR and q(RT)-PCR are the most widely used molecular techniques, especially in developed countries. PCR detects pathogens by amplifying DNA sequences, while q(RT)-PCR quantifies target DNA or RNA for accurate pathogen levels. These techniques excel at identifying known harmful bacteria but struggle to detect unknown or emerging pathogens in large quantities (Zhao et al. 2023). Advanced molecular methods have further expanded our capabilities. NGS techniques, including pyrosequencing, allow comprehensive analysis of water samples' microbial composition through metagenomic investigations. This not only aids in recognizing known pathogens but also uncovers novel or unexpected organisms, enhancing our understanding of microbial populations in water sources (Zhao et al. 2023). Other important molecular methods include oligonucleotide DNA microarrays, which enable simultaneous analysis of thousands of genes, providing comprehensive data on microbial communities (Ramírez-Castillo et al. 2015; Luchi et al. 2020). Fluorescence in situ hybridization (FISH) allows for direct visualization of pathogens in their natural environment, while biosensor-based methods offer the advantage of real-time and on-site monitoring (Ramírez-Castillo et al. 2015).
Each of these methods has its own strengths and limitations. PCR and q(RT)-PCR are sensitive but need extensive preparations. NGS and microarrays are thorough but costly. FISH is direct but labor-intensive. Biosensors are fast but less sensitive. By employing these diverse molecular techniques, researchers and water quality professionals can achieve a more accurate and comprehensive understanding of waterborne pathogen presence and behavior, ultimately improving public health protection and water treatment processes.
AI and machine learning
The integration of AI and machine learning techniques in waterborne disease management marks the beginning of a new era of proactive data analysis and advanced monitoring systems. Since 2015, there has been a consistent rise in the use of these technologies for microbiological analysis, largely due to the rapid development of deep learning algorithms that have improved image segmentation accuracy (Zhang et al. 2022a).
AI-enabled biosensing demonstrates high accuracy rates of 80–100% for rapid pathogen detection in food and agricultural water (Yi et al. 2023). For instance, a study developed a portable, affordable approach using fluorescence microscopy and machine learning on a smartphone to rapidly detect and quantify Giardia lamblia cysts, effectively identifying 12 cysts per 10 mL within 1 h (Koydemir et al. 2015). Similarly, Raman spectroscopy combined with machine learning has shown accuracy rates of 87–95% for rapid identification of foodborne pathogens, offering quick diagnosis of pathogenic bacteria (Yan et al. 2021).
Machine learning algorithms have enhanced predictive models by recognizing detailed patterns and relationships that humans might overlook (Zhong et al. 2021). Deep learning algorithms enable automatic detection of viruses in water samples through image analysis and pattern recognition (Abdeldayem et al. 2022). These methods have shown promising results in predicting the presence of pathogens like Cryptosporidium and Giardia in surface and drinking water, with accuracy rates of 75 and 69%, respectively (Ligda et al. 2020).
The scope of AI and machine learning applications extends to epidemiological studies of foodborne disease outbreaks, offering advantages over traditional systems (Vilne et al. 2019). In underdeveloped nations, machine learning has demonstrated effectiveness in predicting positive instances of waterborne infections, enabling prompt decision-making and saving considerable time (Hussain et al. 2023). Multiple assessments have been conducted on the utilization of AI in drinking water administration, specifically focusing on waterborne illnesses (Xiang et al. 2021; Krishnan et al. 2022; Nusrat et al. 2022; Joy et al. 2023; Maroju et al. 2023). These studies indicate that water resource management and rule implementation can be facilitated by AI and machine learning models. The random forest model accurately predicted positive typhoid cases and malaria cases in 77 and 60% of cases, respectively (Hussain et al. 2023). In studies dealing with WBDs, AI and machine learning have been receiving increasing attention in recent years, demonstrating that their role is critically important (Joy et al. 2021, 2023).
However, integrating AI and machine learning into WBD management faces significant challenges (Nishant et al. 2020). Currently, AI-generated insights are not being fully utilized to develop practical solutions for public health issues (Ahmad et al. 2021). The efficient and accurate detection of waterborne pathogens in drinking and recreational water sources remains a critical challenge in managing and controlling water-related illnesses, particularly in resource-limited settings.
Despite these limitations, AI and machine learning have substantial potential to revolutionize WBD control through efficient and data-driven public health protection. As research advances, the application of AI and machine learning in addressing human-related foodborne and WBDs is expected to increase. This technological progress promises to enhance our ability to detect, predict, and manage waterborne pathogens effectively, ultimately contributing to improved public health outcomes globally.
Remote sensing technologies
The application of remote sensing technologies in the surveillance of water-based illnesses represents a significant advancement in monitoring environmental and public health. These technologies, utilizing satellite and aerial photography, offer a comprehensive assessment of environmental factors contributing to the spread of waterborne infections. Remote sensing methods are employed in ocean-color sensing to gather information on pathogens and water ecology, particularly for organisms like Vibrio cholerae, the primary bacterium responsible for cholera epidemics (Racault et al. 2019). The combination of remote sensing and geographic information systems enables researchers to efficiently detect and predict high-risk areas.
While remote sensing technologies are not as widely used as molecular and nanotechnology methods for waterborne pathogen detection, they are implemented alongside online monitoring sensors to rapidly detect bacteria, protozoa, and viruses. These systems serve as an early warning mechanism for monitoring water quality in distribution networks (Sherchan et al. 2014). A recent study highlights the potential of remote sensing in monitoring non-cholera vibrios in coastal regions, suggesting its future use in estimating human health risk (Semenza et al. 2022). However, the use of remote sensing in waterborne pathogen monitoring faces challenges, including limited detail in satellite imaging and the need for site confirmation permissions. Despite these obstacles, the significance of these technologies in early warning systems and their contribution to water management and public health policy decisions is undeniable.
Current advances in water treatment and potential future focus area
With an increasing demand for potable water due to rising threats to water security, methods for water treatment are also being improved. Various advanced technologies are now being used in addition to and in conjunction with traditional methods to achieve efficient water treatment.
Advanced oxidation processes
Perhaps one of the most studied water treatment processes is AOPs. There are different subtypes of AOPs depending on the treatment used, but the underlying general process is similar. In general, AOPs are reliant on the formation of highly reactive oxygen species to decrease the abundance of harmful microorganisms in water (Kokkinos et al. 2021). AOPs include processes such as ozonation, ozonation coupled with H2O2 and/or ultraviolet (UV) radiation, Fenton and similar reactions, electrochemical oxidation, sonolysis, photocatalysis, and even combinations of these (Monteiro et al. 2015; Galeano et al. 2019; Kokkinos et al. 2020). AOPs are commonly used as a pretreatment or post-treatment to a biological process (Monteiro et al. 2015; Galeano et al. 2019; Kokkinos et al. 2020). In Canada, ozonation UV light is used while ozone treatment is used in Japan (Pakharuddin et al. 2021).
AOPs are known for being able to regulate the abundance of microorganisms in water and are used for their efficiency in disinfection and eco-friendliness compared with more conventional methods (Nieto-Juarez & Kohn 2013; Giannakis et al. 2017; Shabat-Hadas et al. 2017; Marjanovic et al. 2018; Kokkinos et al. 2021). However, there are also various disadvantages for certain AOPs, such as the significant production of ferrous sludge (Fenton and similar processes), costly chemicals (i.e., H2Os, O3), elevated installation, and costly operations for UV/ozone processes; fortunately, these can be remedied by coupling various AOPs with other AOPs or other processes (Kokkinos et al. 2020; Srivastav et al. 2020).
Membrane technologies
Simply put, membrane technologies are used in water treatment by allowing the water to pass through a membrane. Membrane technologies are divided into two major classifications: equilibrium-based and non-equilibrium-based. These are further subdivided into two subtypes depending on whether the process was pressure-driven or not. Of these types, pressure-driven membrane processes are the most widely used. Pressure-driven membrane processes depend on hydraulic pressure to achieve separation. These include microfiltration, ultrafiltration (UF), nano filtration, and reverse osmosis (Obotey Ezugbe & Rathilal 2020). In Malaysia, for example, the UF system is used (Pakharuddin et al. 2021).
Membrane technology has emerged as one of the most used water treatment methods in the past couple of decades due to its multiple benefits (Obotey Ezugbe & Rathilal 2020). In Malaysia, for example, the UF system is used (Pakharuddin et al. 2021). UF is good at filtering out bacteria and viruses, and benefits include lower operating costs, easily upgradable systems, the generation of high-quality clean water, and a compact system that does not require much space (Pakharuddin et al. 2021). However, not all membrane technologies are low cost, so one of the disadvantages is that the cost is too high for small and medium industries (Crini & Lichtfouse 2019). Other disadvantages include high energy requirements, low throughput, and limited flow rates (Crini & Lichtfouse 2019).
Electrocoagulation
The process of electrocoagulation involves the release of metal cations into water through dissolving metal electrodes (Vepsäläinen & Sillanpää 2020). Electrocoagulation uses microelectrical current to remove contaminants, wherein the repulsive forces of particles suspended in water are destabilized or neutralized in order to form larger particles that can be removed from water more easily (Mao et al. 2023).
Electrocoagulation is an advanced water treatment technology that has been mentioned in previous literature as an alternative to chemical coagulation since it is more cost-effective (Crini & Lichtfouse 2019; Ingelsson et al. 2020; Vepsäläinen & Sillanpää 2020; Mao et al. 2023). Other advantages of this method include the efficient elimination of suspended solids, oils, greases, color, and metals; effectiveness in drinking water treatment; and being very effective for the reduction, coagulation, and separation of copper (Crini & Lichtfouse 2019). However, there can be a problem with regards to the formation and cost of treatment of sludge, costly cyclic replacement of electrodes as it dissolves due to oxidation, and the cost of electrical energy consumption for treatment (Crini & Lichtfouse 2019; Mousazadeh et al. 2021; Yasasve et al. 2022).
Biological treatment methods
In general terms, biological treatment methods introduce microorganisms in the water for the biodegradation of organic contaminants (Crini & Lichtfouse 2019). In this process, the biodegradation of micropollutants is dependent on the nature of the micropollutants and redox conditions (Ejhed et al. 2018; Hube & Wu 2021). The use of biological treatment methods for water started in the 1900s, but many improvements have been made to this process since then (Abu Hasan et al. 2020). An example is the biological drinking water treatment (BioDWT), being used in countries such as Canada, China, Croatia, Greece, and the USA, which is dependent on non-pathogenic bacteria acting as a biocatalyst for biochemical oxidation that degrades pollutants in contaminated water (Abu Hasan et al. 2020). Another example is the biologically activated carbon, which is used in countries like Australia and Japan to clarify water (Pakharuddin et al. 2021).
However, a very concerning disadvantage of this method is that the drinking water that is being treated may be exposed to pathogenic microorganism contamination (e.g., E. coli) (Abu Hasan et al. 2020). In BioDWT, for example, microorganism growth can be influenced by multiple factors present in untreated water, which may be difficult to control during biological treatment (Abu Hasan et al. 2020). It can also be difficult to ensure the effectiveness of the method since it is necessary to create an optimally favorable environment, and it requires management and maintenance of the microorganisms (Crini & Lichtfouse 2019).
Integrated and hybrid methods
Most, if not all, of the existing methods for water treatment are used in conjunction with other methods. Some methods are usually used as pretreatment for water before subjecting the water to another method of treatment. Since different methods have different advantages and disadvantages as well as target contaminants (i.e., some methods are more effective in removing certain pathogens), the use of multiple methods is common in water treatment.
For example, Japan uses biologically activated carbon treatment to clarify water but uses ozone treatment for disinfection (Pakharuddin et al. 2021). Crini and Lichtfouse even break down the process of decontamination for industrial wastewaters, which involves pretreatment (through physical-chemical and mechanical methods), primary treatment (through physical-chemical and chemical methods), secondary treatment (through biological treatment and physical-chemical methods), and tertiary treatment (through physical techniques and chemical methods) (Crini & Lichtfouse 2019).
Interdisciplinary frameworks in implementation and research
Interdisciplinary frameworks are essential for effectively addressing the complexity of issues surrounding the transmission and management of WBDs in the context of implementation and research. A suitable research strategy for developing sustainable solutions to prevent water-related infectious diseases must surpass existing approachable ways, such as in monitoring and reporting the current issues. More contributable ways, such as interdisciplinary and transdisciplinary framework approaches, are needed. There are many disciplines contributing to interdisciplinary frameworks, such as (1) public health and epidemiology, (2) social sciences and society situation, (3) economics and policy studies, (4) education, (5) environmental science and engineering, (6) data science and information technology, and (7) communication and awareness. With careful examination of the different disciplines, there are a number of conceptual frameworks for multidisciplinary research in the world (Table 1). The outcomes of the frameworks in each paper differ according to the specific areas involved; however, it is the improvement in the decision-making processes that is associated with the WBDs cases worldwide. One thing to bear in mind is that the reduction of health issues associated with WBDs can be achieved through an interdisciplinary framework, and it should be implemented in each country, especially in developing countries.
Implementation of the interdisciplinary framework in the specific area and global scale
Study country/regions . | Discipline . | Successful framework . | Role in WBDs management . | References . |
---|---|---|---|---|
Tanzania | Epidemiology, public health, policy and governance | Work in progress | Climate change has increased the rate of WBDs in developing countries, Disease tracking and risk assessment, Community engagement | Mboera et al. (2012) |
Mozambique | Epidemiology, climate change, public health | Work in progress | Disease tracking, risk assessment, prevention, control strategies, and extreme weather events increase WBDs and lead to mismanagement | Rusca et al., (2022) |
Northern Europe | Information technology, communication | Positive (smart circular WPM ecosystem) | Data management and technological solutions, and communicating among the people using digital system such as TV channel line | Pirrone et al. (2023) |
Sub-Saharan Africa | Epidemiology, communication, public health | Positive (DPSEEA) | Prevention and control strategies, Regulatory frameworks and policy implementation, Awareness and information, Community engagement and behavior change | Zerbo et al. (2021) |
global | Epidemiology, public health, policy and governance | Work in progress | One health regulatory framework, awareness and information, and prevention and control strategies | Ogunseitan (2022) |
global | Communication, public health infrastructure, social and ecology aspects | Blueprint proposal stage | Public health infrastructure and prevention, community engagement, and behavior change | Wilcox & Colwell (2005) |
global | Public health, policy, and governance, ecology, and epidemiology | Conceptual multidisciplinary health-based system | Socioeconomic interventions, Regulatory frameworks and policy implementation, Disease tracking and risk assessment | Batterman et al. (2009) |
Study country/regions . | Discipline . | Successful framework . | Role in WBDs management . | References . |
---|---|---|---|---|
Tanzania | Epidemiology, public health, policy and governance | Work in progress | Climate change has increased the rate of WBDs in developing countries, Disease tracking and risk assessment, Community engagement | Mboera et al. (2012) |
Mozambique | Epidemiology, climate change, public health | Work in progress | Disease tracking, risk assessment, prevention, control strategies, and extreme weather events increase WBDs and lead to mismanagement | Rusca et al., (2022) |
Northern Europe | Information technology, communication | Positive (smart circular WPM ecosystem) | Data management and technological solutions, and communicating among the people using digital system such as TV channel line | Pirrone et al. (2023) |
Sub-Saharan Africa | Epidemiology, communication, public health | Positive (DPSEEA) | Prevention and control strategies, Regulatory frameworks and policy implementation, Awareness and information, Community engagement and behavior change | Zerbo et al. (2021) |
global | Epidemiology, public health, policy and governance | Work in progress | One health regulatory framework, awareness and information, and prevention and control strategies | Ogunseitan (2022) |
global | Communication, public health infrastructure, social and ecology aspects | Blueprint proposal stage | Public health infrastructure and prevention, community engagement, and behavior change | Wilcox & Colwell (2005) |
global | Public health, policy, and governance, ecology, and epidemiology | Conceptual multidisciplinary health-based system | Socioeconomic interventions, Regulatory frameworks and policy implementation, Disease tracking and risk assessment | Batterman et al. (2009) |
The updated driving force-pressure-state-exposure-effect-action (DPSEEA) framework permits the intervention of behavioral parameters and implementation of urban public health rules and regulations (Zerbo et al. 2021). Pressure-state-response and driving force-pressure-state-impact-response are not preferable since they only focus on environmental cases and human health cases without specific targeted intervention, respectively. To implement preventive strategies, such as policies and program development, that are informed by One Health and bridge the gaps between scientific knowledge and action, it is necessary to integrate various interdisciplinary and interprofessional frameworks (Ogunseitan 2022). These frameworks are currently requiring attention from scholarly journals, funding agencies, and international negotiation forums. Implementing digital transition technologies can enhance the sustainability of the aquatic passenger mobility system while simultaneously supporting a circular economy (Pirrone et al. 2023). The exploration, preparation, implementation, sustainment framework involves stakeholder engagement within the implementation system, and it helps to improve the usage of scientific frameworks (Moullin et al. 2020). Northern Europe and Sub-Saharan Africa are making progress in their frameworks, specifically with the smart circular waterborne passenger mobility (WPM) Ecosystem and the DPSEEA model, respectively (Table 1). Effective management of WBDs and successful application of the interdisciplinary framework are achieved through collaborative efforts rather than individual initiatives.
Understanding the differences between interdisciplinary and transdisciplinary research is vital for effective collaboration and issue-relieving in complicated areas, such as public health, environmental science, social science, engineering, and epidemiology. Nowadays, interdisciplinary and transdisciplinary research are very effective tools to access the integrated approach and involve the active collaboration of researchers from cross-disciplinary areas and stakeholders from outside of academia, such as industry experts, and policymakers. A perfect holistic framework is yet to be made for the WBDs research area; however, the steps for improvement are being centralized around the world (Table 1). In order to develop effective strategies for the prevention and control of these diseases, we may integrate the strengths of a variety of professions. This will ultimately lead to improvements in public health outcomes and ensure that people have access to safe water in an environmentally sound way. In addition, conducting comprehensive research on WBDs demands a multidisciplinary approach that involves collaboration among various scientific disciplines, including microbiology, biochemistry, epidemiology, environmental science, and public health. However, the integration of efforts across these diverse fields presents unique challenges. Variations in communication styles and research methodologies can impede the development of a unified and comprehensive understanding of these diseases. Overcoming these interdisciplinary barriers is essential for crafting a more integrated and effective strategy to combat WBDs, ultimately leading to improved global health outcomes.
Climate change's impact on WBDs and consequences on human health
Flowchart illustration of the climate change impact on WBDs and their interaction and consequence.
Flowchart illustration of the climate change impact on WBDs and their interaction and consequence.
The intensifying harmful connection between infections and humans due to climate change and extreme weather events is evident, with pathogens primarily being strengthened by these environmental shifts (Mora et al. 2022). The impact of climate change on WBDs extends beyond physical health, potentially affecting mental health and socioeconomic stability of communities (Cianconi et al. 2020). To mitigate these impacts, strategies such as improving water sanitation, enhancing water treatment, increasing public awareness, bolstering disease surveillance, and implementing early warning systems and water, sanitation, and hygiene (WASH) infrastructure are crucial. Furthermore, both global and local policies must prioritize climate adaptation methods that consider the nexus between climate change, water security, and public health. This comprehensive approach is essential for addressing the complex challenges posed by climate changes to WBDs and public health.
Interrelationship between the SDGs and waterborne diseases
The United Nations introduced the SDGs in 2015, aiming to achieve various objectives by 2030. These objectives include preserving water quality and hygiene, reducing poverty, protecting biodiversity, and attaining peace and prosperity (International Council for Science 2017). The SDGs framework comprises 17 goals with 169 targets and 247 indicators, providing a comprehensive roadmap for global development. WBDs pose a significant threat to human health, especially in developing countries. Their prevention and control are crucial on a global scale, as they directly impact several SDGs. Notably, WBDs are closely linked to Goals 3 (Good Health and Well-being), 6 (Clean Water and Sanitation), 11 (Sustainable Cities and Communities), 13 (Climate Action), and 17 (Partnerships for the Goals). Understanding the intricate connections between WBDs and these SDGs is essential for effectively addressing global health challenges. This understanding can help resolve conflicts, reduce confusion, and prevent the neglect of key issues in sustainable development and public health (Hall et al. 2020; Igere & Ekundayo 2020; Mraz et al. 2021; Jung et al. 2023). By recognizing these interrelationships, policymakers, researchers, and practitioners can develop more integrated and effective strategies to combat WBDs while simultaneously advancing multiple sustainable development objectives.
SDG No 3. Good health and well-being
WBDs are fundamentally linked to SDG 3, as they have a significant impact on human health worldwide. A wide range of illnesses, including cholera, dysentery, hepatitis A, typhoid, cryptosporidiosis, paratyphoid, salmonellosis, rotavirus infections, bacillary dysentery, leptospirosis, and polio, are directly associated with poor water quality and inadequate sanitation (Manetu & Karanja 2021). Improvements in WASH practices contribute to reducing the incidence of these diseases, in line with the objectives of SDG 3. The attainment of good health and well-being is closely tied to access to clean, high-quality water. In developing countries where WBDs are prevalent, these illnesses present a substantial obstacle to realizing the SDGs. SDG Target 3.3, which focuses on combating infectious diseases, is particularly relevant to WBD cases (WHO Headquarters (HQ) 2015). Addressing WBDs through comprehensive WASH strategies is not only crucial for achieving SDG 3, but also serves as a catalyst for progress across multiple SDGs, underscoring the interconnected nature of global health and sustainable development.
SDG No 6. Clean water and sanitation
SDG 6 focuses primarily on ensuring the availability of clean water and sustainable water sanitation for all. This goal has a direct relationship with WBDs, as improving water quality, sanitation, and personal hygiene can effectively reduce their occurrence and spread. Advancements in water treatment processes, such as AOP, increase the likelihood of reducing pathogens in water, thus contributing to the achievement of Goal 6. However, many countries still need to strengthen their water management and sanitation practices to improve water quality and human health (Wang et al. 2022). SDG 6 emphasizes the importance of public access to clean water and sanitary facilities in reducing disease spread. SDG Target 6.3 is particularly relevant, as it focuses on improving water quality by reducing pollution, including hazardous chemicals and materials (Alcamo 2019; Arora & Mishra 2022). The implementation of SDG 6 directly impacts the reduction of WBDs. Improved access to clean water and sanitation significantly decreases illnesses such as cholera and dysentery while also enhancing overall public health through better nutrition and food safety. Achieving SDG 6 thus contributes to multiple SDGs, including health improvement and poverty reduction. Countries must focus on improving water management policies, investing in sanitation infrastructure, and strengthening disease prevention education to effectively address these interconnected challenges.
SDG No 11. Summon sustainable cities and communities
SDG 11, while not explicitly focused on WBDs, significantly contributes to their reduction through its emphasis on sustainable urban development. Effective urban planning, as outlined in this goal, can substantially decrease the risk of waterborne infections by implementing sound waste management practices and providing safe water and sanitation infrastructure in urban areas. A notable synergy exists between SDG 3 (Good Health and Well-being) and SDG 11, particularly evident in Target 11.5. This target aims to reduce casualties from water-related disasters, with a special focus on impoverished areas and sustainable urban development (WHO Headquarters (HQ) 2015). Access to clean water, a key component of sustainable cities, is crucial for creating a safe and healthy environment for urban dwellers and can greatly reduce the incidence of WBDs. The interconnection between sustainable urban development and public health challenges is clearly demonstrated in the pursuit of SDG 11. Case studies from South Africa and Nepal illustrate the nexus between sustainable urban development and public health challenges, demonstrating how addressing urban infrastructure and sustainability issues can positively impact health outcomes, including the reduction of WBDs (Shrestha et al. 2020; Matamanda et al. 2022). In essence, SDG 11's focus on creating sustainable, resilient, and healthy urban environments inherently supports the reduction of WBDs, underscoring the interconnected nature of the SDGs and their collective impact on public health.
SDG No 13. Climate action
Climate change significantly impacts water quality and quantity, potentially accelerating the spread of WBDs to humans. Extreme weather events, such as flooding, drought, sea-level rise, and temperature changes, can degrade water resources, leading to a higher risk of WBDs, especially in areas with inadequate monitoring and environmental management (Moreira et al. 2020; Teymouri & Dehghanzadeh 2022; Jung et al. 2023). The increasing vulnerability to waterborne infections is a direct consequence of climate change (Goal 13), which exacerbates water scarcity and pollution. This relationship underscores the importance of developing and implementing climate adaptation strategies, particularly in the context of water management and public health. Key measures to address this challenge include strengthening WASH infrastructure and practices, implementing effective early warning systems for extreme weather events and disease outbreaks, and enhancing water treatment and distribution systems to cope with changing environmental conditions. Consequently, addressing climate change is critical in tackling WBDs globally. The interconnection between climate action and waterborne disease prevention highlights the need for integrated approaches in policy-making and public health strategies. Neglecting these interlinked issues could significantly endanger populations worldwide, emphasizing the urgency of climate action in the context of global health.
SDG No 17. Strengthen the means of implementation and revitalize the global partnership for sustainable development
SDG 17, which focuses on strengthening global partnerships for sustainable development, has an indirect but significant connection to the fight against WBDs. This goal aims to enhance implementation procedures and foster international collaboration, crucial for addressing complex global challenges such as WBDs. For developing nations, SDG17 is particularly important as it promotes strong relationships and partnerships necessary for achieving the SDGs (Jung et al. 2023). These partnerships can facilitate knowledge transfer, resource sharing, and capacity building, all essential for improving water management and sanitation practices that directly impact WBDs. Furthermore, SDG 17 encourages research collaboration on WBDs and advanced control techniques (Robertson et al. 2020). Such collaborations can lead to innovative solutions and more effective strategies for preventing and controlling WBDs globally. By strengthening international cooperation and partnerships, SDG 17 creates a framework that supports the achievement of other SDGs, including those directly related to water quality and public health. This interconnected approach is vital for addressing the multifaceted challenges posed by WBDs in a globalized world.
CONCLUSION
This paper presented an overview of recent advancements in pathogen detection and water treatment for WBD research. Remote sensing and machine learning technologies show considerable promise in pathogen detection, while water-based epidemiology offers potential as a comprehensive and efficient early detection method for monitoring public health at the community level. Waterborne pathogens, including bacteria, viruses, and protozoa, pose significant risks to both human health and the environment. To address these risks effectively, it is crucial to continuously advance detection technologies for prompt and accurate identification of these microorganisms. Utilizing diverse techniques and emerging technologies will be essential in addressing existing knowledge gaps and pushing the boundaries of detection capabilities.
The complexity of WBD research necessitates an interdisciplinary approach. The paper highlighted the urgent need for an interdisciplinary framework in addressing WBDs globally. More effective interdisciplinary and transdisciplinary research approaches need to be implemented. The WBDs research landscape is vast and complex, often depending on geographical and socioeconomic factors. Addressing WBDs involves overcoming challenges in detection technology, particularly in adhering to the WHO's ASSURED criteria, and dealing with the complexities of water sample analysis. Emphasizing multidisciplinary cooperation is vital to bridge laboratory research with practical disease management. The key lies in integrating diverse scientific disciplines and harmonizing methodologies to formulate an effective response. This comprehensive approach aligns with several SDGs. The paper clearly articulated the interrelationship between SDGs and WBDs, with goals 3, 6, 11, 13, and 17 being most closely interrelated with WBDs.
Understanding the challenges of water security and climate change is crucial for effectively combating the spread of WBDs worldwide. Future research efforts must focus on advancements in detection and treatment technologies. It is imperative for the scientific community, policymakers, and public health officials to collaborate in order to leverage these advancements, ensuring secure water availability and advocating for equitable distribution of health resources globally. In conclusion, this comprehensive approach promises not only to enhance global health outcomes but also to ensure a safer, healthier future for communities worldwide, especially those most vulnerable to WBDs.
AUTHOR CONTRIBUTIONS
N.A.K., S.N., and H.K. had the idea for the article and were responsible for the review design. N.A.K., R.M.L., A.S. and J.M. performed a literature search, analyzed the data, and prepared figures. N.A.K., R.M.L., and A.S. drafted the main text. H.K. and S.N. polished the manuscript. All authors participated in the discussion and editing.
FUNDING
This research was funded by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (grant numbers 2019R1I1A2A01057002 and 2019R1A6A1A03033167), Korea Ministry of Environment as ‘The SS (Surface Soil conservation and management) projects; 2019002820004’, and the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT): RS-2023-00252325.
DATA AVAILABILITY STATEMENT
All relevant data are included in the paper or its Supplementary Information.
CONFLICT OF INTEREST
The authors declare there is no conflict.