Introduction
The Middle East’s protracted and overlapping conflicts have created a humanitarian landscape in which health systems must simultaneously manage mass casualties and sustain core public-health functions. Yet the health consequences of war extend well beyond direct injury. Damage to essential civilian infrastructure, particularly water, sanitation, and hygiene (WASH) systems, can generate broad, delayed, and cumulative effects that reshape disease risk long after the initial damage event.Reference Talhami and Zeitoun 1 –Reference Al-Saidi, Roach and Al-Saeedi 2 Unsafe WASH remains a major global health burden; WHO estimates that in 2019 at least 1.4 million deaths and 74 million disability-adjusted life years were attributable to unsafe drinking WASH. 3 In 2024, 2.1 billion people still lacked safely managed drinking water and 3.4 billion lacked safely managed sanitation globally, underscoring that conflict often strikes systems that are already precarious or incomplete. 4 In settings of conflict, these baseline deficits are intensified by displacement, overcrowding, interrupted vaccination, supply-chain interruption, malnutrition, and reduced access to routine care, with children at particularly high risk of diarrheal disease and other WASH-sensitive conditions.Reference Talhami and Zeitoun 1 , 5 In this review, “systems failure” refers to the combined breakdown of the infrastructure, energy, supply-chain, workforce, governance, financing, and surveillance functions needed to keep WASH services operating safely.
In conflict settings, WASH collapse is rarely a single-point technical breakdown. Rather, it is a systems failure in which physical damage to wells, pipelines, pumping stations, desalination units, wastewater facilities, and solid-waste services interacts with electricity outages, fuel shortages, restricted movement, depleted technical workforces, and fragmented governance.Reference Talhami and Zeitoun 1 –Reference Al-Saidi, Roach and Al-Saeedi 2 , 6 These interdependencies matter because safe water service depends not only on infrastructure but also on chemicals, spare parts, laboratory capacity, maintenance, financing, and reliable energy, while sanitation depends on collection, conveyance, treatment, and safe disposal across connected networks.Reference Talhami and Zeitoun 1 –Reference Al-Saidi, Roach and Al-Saeedi 2 , 6 When conflict becomes prolonged, the result is not merely episodic disturbance but progressive degradation in service quality, continuity, and coverage, with increasingly severe effects on households, shelters, municipalities, and health care facilities.Reference Talhami and Zeitoun 1 –Reference Al-Saidi, Roach and Al-Saeedi 2 This systems perspective is especially relevant in the Middle East, where protracted conflict, severe access constraints, displacement, economic crisis, and environmental stress have repeatedly converged to destabilize already vulnerable public utilities and local service delivery arrangements.Reference Al-Saidi, Roach and Al-Saeedi 2 , Reference Abuawad, Griffiths and Edwards 7 –Reference Qamar, Malik and Yousuf 12
The public-health implications of WASH disruption are broader than outbreaks alone. From a disaster medicine perspective, WASH failure is a cascading emergency that increases disease risk, disrupts health care delivery, and complicates humanitarian response operations. Protecting these systems is essential for preparedness and health system resilience. In addition to increasing fecal-oral transmission and exposure to unsafe water, WASH failure undermines infection prevention and control, environmental cleaning, safe childbirth, surgery, wound care, dialysis, and waste management within health care facilities. 13 –Reference Bouzid, Cumming and Hunter 15 This is not a marginal systems issue. WHO and UNICEF estimate that in 2022 one in five health care facilities globally lacked basic water services and 39% lacked basic hygiene services, affecting the safety and quality of care for billions of people. 13 These deficits are particularly consequential in conflict settings, where hospitals, field clinics, and displacement shelters must function under conditions of crowding, insecure access, damaged infrastructure, and fuel dependency. At the sector level, global monitoring further shows that many countries have WASH policies and plans on paper, yet far fewer report sufficient financing, workforce capacity, and implementation readiness to deliver or sustain services. 6 This gap between formal planning and operational capability helps explain why conflict shocks can rapidly precipitate public-health emergencies once water and sanitation systems begin to fail.
Across the Middle East, recent evidence from Gaza and the occupied Palestinian territory, Yemen, Syria, Lebanon, and Iraq indicates that WASH disruption is not a peripheral humanitarian concern but a policy-relevant public health emergency.Reference Abuawad, Griffiths and Edwards 7 –Reference Qamar, Malik and Yousuf 12 These settings were selected because they illustrate different forms of conflict-related WASH stress, including acute infrastructure destruction, protracted service deterioration, displacement-related overcrowding, governance fragmentation, and restricted humanitarian access. In policy terms, the central concern is not only that water and sanitation systems are damaged, but that their failure creates a preventable pathway of harm: conflict-related damage, energy shortages, access restrictions, underfunding, and weak governance interrupt water supply, wastewater management, sanitation, solid-waste services, and health care facility hygiene. These failures increase exposure to unsafe water, untreated sewage, poor hygiene conditions, and unsafe care environments, affecting displaced households, children, patients, health care workers, municipalities, and humanitarian responders. Accordingly, this article presents a policy-oriented narrative synthesis of peer-reviewed and humanitarian evidence published between 2020 and 2026. Rather than treating WASH as a separate engineering or support sector, the paper frames WASH as essential health infrastructure whose disruption can undermine disease control, continuity of care, and civilian safety.Reference Talhami and Zeitoun 1 – 3 , 6 , 16 This review has two objectives: first, to synthesize the mechanisms through which conflict-related WASH system failure generates public health consequences in Middle Eastern conflict-affected settings; and second, to identify practical policy and preparedness priorities for health authorities, humanitarian agencies, donors, and policymakers during conflict and early recovery. While previous reviews have documented WASH challenges in humanitarian settings broadly, no recent review appears to have synthesized WASH-health linkages across multiple conflict-affected Middle Eastern settings during the post-2020 period.Reference Schillinger, Ozerol and Guven-Griemert 17 –Reference Als, Meteke and Stefopulos 18
Methods
This policy-oriented narrative review synthesized peer-reviewed and humanitarian evidence on conflict-related WASH system failure and associated public health consequences in selected Middle Eastern settings. Sources were identified through structured searches of PubMed, Scopus, and Google Scholar and targeted searches for reports from WHO, UNICEF, OCHA, UNEP, and GTFCC. Searches were completed in March 2026 and covered English-language materials published from January 2020 through March 2026; earlier foundational evidence and technical guidance were retained when relevant to preparedness. The core search combined four concepts: (WASH OR water OR sanitation OR hygiene OR wastewater OR sewage OR “solid waste”) AND (conflict OR war OR humanitarian OR displacement) AND (health OR cholera OR diarrhea OR hepatitis OR “infection prevention”) AND (Gaza OR Palestine OR Yemen OR Syria OR Lebanon OR Iraq). Terms and syntax were adapted to each platform.
Sources were eligible when they provided setting-specific empirical, surveillance, operational, environmental, or policy evidence on WASH disruption, health outcomes, health care facility impacts, environmental contamination, response barriers, or preparedness measures in at least one selected setting. Materials outside the geographic or temporal scope, sources without relevant WASH-health or preparedness content, duplicate reports, and items lacking sufficient methodological or institutional provenance were excluded. Titles and abstracts or executive summaries, followed by full texts, were assessed for relevance. Sources were selected for narrative synthesis without duplicate independent screening, and a formal PRISMA flow diagram was not prepared.
No standardized extraction form or formal risk-of-bias instrument was used. To support consistent comparison, relevant information was charted under common domains: conflict context; WASH disruption mechanism; service-function indicator; environmental or population exposure; reported health signal; operational barrier; response measure; and preparedness implication. When sources provided differing estimates, reporting periods, case definitions, geographic coverage, source provenance, and update dates were compared. More recent primary or official sources were prioritized for operational estimates; noncomparable estimates were retained separately or qualified rather than pooled. Findings were synthesized across settings to identify recurring mechanisms, contextual differences, and shared preparedness lessons. Formal evidence grading and meta-analysis were not performed.
The five settings were selected as analytical contrast cases rather than as a statistically representative regional sample. Selection was based on the following criteria: (1) active armed conflict, conflict spillover, or post-acute fragility during 2020-2026; (2) documented large-scale WASH damage or service interruption affecting civilians; (3) public health surveillance or humanitarian reporting on health consequences; and (4) sufficient variation in conflict intensity, governance, displacement, and humanitarian access to support comparison. Gaza and the occupied Palestinian territory illustrate acute infrastructure destruction and severe access restriction; Yemen illustrates protracted conflict, institutional fragmentation, and underfunded services; Syria illustrates long-term infrastructure attrition, displacement, and fragmented water governance; Lebanon illustrates conflict spillover, displacement-related service demand, and economic-system deterioration outside sustained nationwide warfare; and Iraq illustrates episodic WASH-sensitive outbreaks within a mixed-stability context. Together, these cases permit comparison of different triggers and tempos of failure while examining whether common mechanisms and preparedness lessons recur across settings.
Results
Across the selected settings, evidence was organized using the analytical pathway shown in Figure 1. Conflict-related damage and operational constraints can reduce the capacity to produce safe water, disinfect water supplies, pump and treat sewage, manage waste, and sustain hygiene in health care facilities.Reference Talhami and Zeitoun 1 –Reference Al-Saidi, Roach and Al-Saeedi 2 , 6 , 13 The resulting service failures may increase reliance on unsafe or insufficient water, sewage exposure, crowding around limited water points, unsafe household storage, and inadequate environmental cleaning and waste handling.Reference Abuawad, Griffiths and Edwards 7 – 8 , 13 , 19 – 21 At the same time, insecurity, fuel shortages, restricted entry of critical inputs, and surveillance disruption can prolong service loss and weaken outbreak detection and clinical response. 8 , 13 , 21 The arrows in the framework represent a reasonable systems pathway for organizing the reviewed evidence, not proof of direct causation in every setting.
Conceptual pathway from conflict pressure to WASH-related public health consequences and preparedness intervention.
Note: Preparedness interventions may act at multiple points by protecting workers and infrastructure, maintaining energy and essential inputs, restoring service functions, strengthening surveillance and clinical continuity, and building decentralized redundancy.
Figure 1 Long description
A vertical six-box pathway linked by downward arrows. Conflict pressures include armed violence, displacement, and access restrictions. These lead to system disruption through infrastructure damage, energy and fuel loss, workforce threats, and governance and financing gaps. Next, WASH service failure includes unsafe or insufficient water, interrupted chlorination, sewage overflow, and disrupted waste and health care facility hygiene. Exposure and response constraints then include fecal-oral and environmental exposure plus weakened surveillance, infection prevention and control, and clinical continuity. Public health consequences include diarrheal illness and outbreak risk, hepatitis A, unsafe care environments, and cumulative population harm. The final box shows preparedness interventions across the pathway: immediate protection and continuity, medium-term restoration, and long-term resilient redundancy.
Regional Patterns of WASH Disruption
Gaza Strip and the Occupied Palestinian Territory
Since October 2023, Gaza has experienced severe WASH system collapse under high-intensity conflict.Reference Abuawad, Griffiths and Edwards 7 , Reference Al Bakri, Khader and Khatib 22 According to the WASH Cluster, as cited in UNICEF’s Humanitarian Situation Report dated 31 August 2025, all wastewater treatment had ceased because none of Gaza’s seven wastewater treatment plants had been operational since October 2023. This refers specifically to the loss of treatment capacity. In contrast, the estimate that only about 30% of wastewater facilities were functional refers to broader components of wastewater service that remained partially operational. Because wastewater treatment had ceased and the wider wastewater system was severely impaired, sewage could not be safely collected, treated, and discharged, resulting in untreated sewage flowing into streets, homes, and the sea, with widespread reliance on makeshift latrines.Reference Abuawad, Griffiths and Edwards 7 , 19 , Reference Ali, Rehman and Lee 23 Reporting by the United Nations Office for the Coordination of Humanitarian Affairs (OCHA) illustrates how water supply has become both technically constrained and quality-compromised. In OCHA’s Gaza Humanitarian Response Update for 16-29 March 2025, daily water production was reported to rely heavily on municipal groundwater wells. OCHA noted that even with treatment, well water typically has high salinity and nitrate concentrations exceeding WHO drinking-water benchmarks and is therefore largely limited to domestic and hygiene uses rather than safe drinking.Reference Abuawad, Griffiths and Edwards 7 – 8 The same report highlights system fragility driven by electricity and access constraints (for example, electricity interruptions affecting desalination) and extensive network damage, with high distribution losses.Reference Al-Saidi, Roach and Al-Saeedi 2 , 8
WASH services in health care facilities have deteriorated in parallel. The WHO/UNICEF 2025 global progress report on WASH, waste and electricity in health care facilities reported that, in the occupied Palestinian territory, especially Gaza, the proportion of health care facilities reporting water availability remained below 42% between November 2024 and February 2025, and nearly 60% lacked reliable access. 13 UNEP’s second environmental assessment, released on September 23, 2025 and covering impacts up to September 1, 2025, reported that Gaza’s two constructed solid-waste sites had been inaccessible to civilians since October 2023. Limited disposal options and fuel constraints contributed to hazardous and medical-waste management challenges, including transporting medical waste with general waste to temporary dump sites for co-disposal. These conditions indicate sanitation-related public health risks from disrupted solid-waste and medical-waste management, particularly where temporary dump sites lacked sanitary controls. 24
Yemen
In contrast to Gaza’s acute, high-intensity destruction, Yemen represents protracted WASH decline under sustained conflict, institutional fragmentation, economic crisis, and environmental stress.Reference Al-Saidi, Roach and Al-Saeedi 2 The Yemen humanitarian planning baseline for 2025 described WASH infrastructure as widely damaged and insufficiently maintained, with 15.2 million people requiring WASH assistance. 9 A 2025 operational snapshot from the Norwegian Refugee Council similarly reported severe funding gaps and unmet needs. 25 In March 2026, OCHA estimated that 14.4 million people required WASH assistance, including 4.6 million facing critical severity. 26 Recurrent flooding and drought further constrained safe water and sanitation, sustaining conditions favorable to waterborne disease transmission, including cholera. 26
Syria
Syria shares Yemen’s pattern of prolonged infrastructure attrition but adds extensive displacement, power constraints, drought, and fragmented water governance. UNICEF’s October 4, 2022 cholera reporting described large-scale destruction of water and sanitation infrastructure and noted that 47% of the population relied on alternative and often unsafe water sources to meet or supplement water needs.Reference Alhaffar, Moreno Gomez and Sigua 10 , 20 , 27 GTFCC characterized the 2022-2024 cholera waves as occurring amid inadequate WASH services, overburdened health infrastructure, and fragmented surveillance shaped by conflict and displacement.Reference Alhaffar, Moreno Gomez and Sigua 10 , 28 Scholarly analysis further identified political constraints on water governance and humanitarian response as contributors to outbreak vulnerability.Reference Alhaffar, Moreno Gomez and Sigua 10 , Reference Tarnas, Karah and Almhawish 29
Lebanon
Unlike the active battlefield and protracted-war settings, Lebanon illustrates conflict spillover combined with refugee pressure, financial collapse, and service deterioration in underserved and crowded areas. A detailed epidemiological account of the 2022-2023 cholera outbreak reported spread across all governorates and identified displacement and degraded water and sanitation conditions within the wider humanitarian emergency as important contextual risks.Reference Abiad, Abubakar and Hilal 11
Iraq
Iraq provides a mixed-stability contrast in which recurrent water-quality pressures and episodic outbreaks persist despite lower and geographically uneven conflict intensity. During the 2022 cholera episode, WHO reporting documented confirmed cases and concurrent acute diarrhea signals through early warning surveillance, illustrating the continued importance of monitoring WASH-linked diseases.Reference Qamar, Malik and Yousuf 12 , Reference Sabir, Hama and Salih 30 – 31
Cross-Setting Synthesis of Failure Mechanisms
Comparison across the 5 settings identified 4 recurring operational failure mechanisms despite different conflict patterns: (1) damage or attrition of water, wastewater, and waste infrastructure; (2) dependence on electricity, fuel, chemicals, replacement parts, and laboratory capacity; (3) restrictions on movement and threats to WASH workers; and (4) fragmented governance, financing, and coordination. These mechanisms converged on similar service losses, including reduced water quantity and quality, interrupted chlorination, sewage overflow, unsafe waste handling, and weakened health care facility WASH. The main difference was the trigger and tempo: acute destruction in Gaza, protracted attrition in Yemen and Syria, conflict spillover and economic collapse in Lebanon, and episodic vulnerability within Iraq’s mixed-stability context.
The comparative contribution of this review is therefore a transferable failure-to-harm pathway rather than another inventory of country-specific impacts. WASH-related health risk emerged when underlying system fragility and operational constraints jointly impaired essential services, increased environmental and fecal-oral exposure, and simultaneously weakened surveillance and clinical response. This explains why similar public health signals can occur under different conflict conditions and identifies shared preparedness levers: protect assets and workers, maintain energy and critical inputs, monitor WASH and health indicators together, and build decentralized service redundancy.
Across settings, WASH disruption occurred alongside measurable public health signals, including cholera re-emergence or spread in Syria and Lebanon, sustained cholera burden in Yemen, diarrheal disease signals, and a sharp increase in suspected hepatitis A in Gaza.Reference Abiad, Abubakar and Hilal 11 , 20 – 21 , 28 –Reference Tarnas, Karah and Almhawish 29 , 32 – 34 These observations do not establish a single direct causal pathway for every outcome, but they show a recurring pattern in which disrupted water supply, unsafe sanitation, crowding, and reduced disinfection capacity created conditions favorable to WASH-sensitive disease transmission.Reference Abuawad, Griffiths and Edwards 7 – 8 , 20 – 21 , 32 Table 1 summarizes these WASH-health links.
Illustrative WASH disruption pathways and documented public health signals in conflict-affected Middle Eastern settings (2020-2026)
Table 1. Long description
Five settings are compared. Gaza/oPt: wastewater treatment stopped and WASH services were severely disrupted; acute watery diarrhea and suspected hepatitis A increased, and health care facility water availability was below 42%, with nearly 60% lacking reliable access. Yemen: chronic WASH damage, floods, drought, and funding gaps coincided with 249,900 suspected cholera cases and 861 deaths in 2024 and closure of treatment services. Syria: infrastructure damage, power loss, drought, unsafe water, displacement, and fragmented governance accompanied cholera’s return in 2022 after over 10 years; 47% relied on alternative or unsafe water. Lebanon: degraded WASH conditions amid economic and refugee pressures accompanied 8,072 cholera cases, including 671 confirmed and 23 deaths, in 2022-2023. Iraq: water-quality stress was reflected in confirmed cholera and acute diarrhea signals in 2022. Shared preparedness needs are safe water, service continuity, surveillance, and outbreak response.
Note: The table reports documented public health signals and service-function indicators available from the reviewed sources. In conflict settings, surveillance gaps, restricted access, population movement, and damaged reporting systems may lead to underestimation of true disease burden. For health care facilities, the reviewed sources documented water unreliability and disrupted waste management, which are established IPC risk pathways 13 -Reference Bouzid, Cumming and Hunter 15; however, setting-specific data on hospital-acquired infections or health care worker illness were not consistently available.
Public Health Consequences
Across the five settings, three consequence pathways recurred: fecal-oral and waterborne transmission, environmental exposure to untreated sewage and waste, and degradation of WASH-dependent clinical care. Quantitative signals are reported where available, but surveillance disruption and differing case definitions preclude direct comparison of disease burden across settings.
A prominent regional signal has been cholera re-emergence or spread in settings where the disease had been absent for decades or was not endemic. WHO’s Eastern Mediterranean regional outbreak report for 2022 documented acute watery diarrhea or suspected cholera in 4 of the 5 study settings: Iraq, Lebanon, Syria, and Yemen. 33 , Reference Balkhy 37 This distribution underscores regional and cross-border vulnerability but does not distinguish the contribution of infrastructure failure from those of other transmission dynamics. In Syria, WHO situation reporting confirmed early outbreak detection in Aleppo in August 2022, followed by rapid spread to multiple governorates. 34 This pattern is consistent with service disruption and population movement because damaged water and sanitation infrastructure, electricity shortages affecting pumping, drought-related water scarcity, and reliance on alternative or unsafe water sources increased exposure to contaminated water, while displacement and movement between affected communities facilitated wider geographic spread.Reference Alhaffar, Moreno Gomez and Sigua 10 , 20 , 28 –Reference Tarnas, Karah and Almhawish 29 , 34 Syria’s cholera outbreak is consistent with a pathway in which conflict-related WASH degradation may have facilitated the re-emergence and sustained transmission of a disease that had not been reported in the country for more than a decade.Reference Alhaffar, Moreno Gomez and Sigua 10 , 28 , 34
In Lebanon, the relevance of conflict to WASH risk is indirect but important. The country’s WASH vulnerability was shaped by overlapping humanitarian pressures, including displacement and refugee settlement patterns linked to the Syrian crisis, economic collapse, and service deterioration in underserved and crowded areas. Within this context, the 2022-2023 cholera outbreak analysis reported 8,072 cases, including 671 laboratory-confirmed cases, and 23 deaths between October 2022 and June 2023.Reference Abiad, Abubakar and Hilal 11 These conditions help explain how degraded water and sanitation services in a conflict-affected humanitarian environment can support the spread of WASH-sensitive disease, even outside an active battlefield setting.Reference Abiad, Abubakar and Hilal 11 , 33
Yemen represents a different pattern: prolonged conflict, institutional fragmentation, damaged infrastructure, and underfunded response capacity have coincided with a sustained high burden of WASH-associated disease. As of 1 December 2024, WHO reported 249,900 suspected cholera cases and 861 associated deaths in Yemen since the beginning of 2024. 32 WHO also reported that funding shortfalls led to the closure of 47 diarrhea treatment centers and 234 oral rehydration corners between March and the end of November 2024, showing how service disruption affects not only disease exposure but also treatment and outbreak-control capacity. 32
In Gaza, while epidemic cholera has not been formally established, WHO public health situation analyses in 2025 repeatedly identified acute watery diarrhea among the most frequently reported conditions and reported diarrheal surges alongside restricted access to chlorination supplies, including chlorine tablets, needed for household and system-level water disinfection. 21 More broadly, the regional pattern suggests that fragmented surveillance, delayed response, and cross-border vulnerability can allow WASH-related outbreaks to spread or persist across neighboring conflict-affected settings. 38 – 39 In Gaza, hepatitis A provides a clearer example of the sanitation-collapse pathway. Hepatitis A is transmitted mainly through the fecal-oral route, and the risk increases when people lack safe water, adequate sanitation, hygiene supplies, and reliable waste management. WHO’s Public Health Situation Analysis reported more than 3,000 cases of acute jaundice syndrome in 2025 and approximately 40,000 suspected hepatitis A cases between October 2023 and October 2024, compared with very low reported levels in 2022, while also noting limited laboratory confirmation capacity.Reference Abuawad, Griffiths and Edwards 7 , 21 In this context, the increase is consistent with overcrowding, unsafe water access, inadequate sanitation, and sewage exposure following the collapse of WASH services.
Health system functionality can be compromised by WASH failure because safe care depends on reliable water, hygiene materials, environmental cleaning, sterilization, and safe waste handling. When water is unavailable or unreliable, opportunities for hand hygiene decrease, cleaning of patient-care areas becomes inconsistent, sterilization and reprocessing of equipment may be interrupted, and safe management of infectious waste becomes more difficult. The WHO/UNICEF global report’s Gaza/oPt box illustrates how reduced water availability and disrupted health care waste management can weaken core clinical functions, including infection prevention and control, maternity and neonatal care, surgery, wound care, and dialysis. 13 –Reference Bouzid, Cumming and Hunter 15 These facility-level failures also have wider public health consequences because patients, caregivers, health workers, and displaced populations may be exposed to unsafe hygiene conditions inside facilities and to untreated sewage and poorly managed waste outside them. In Gaza, UNICEF described untreated sewage spilling into public spaces and the sea, while UNEP highlighted temporary dump sites lacking sanitary controls and constrained medical-waste management.Reference Abuawad, Griffiths and Edwards 7 , 19 , Reference Al Bakri, Khader and Khatib 22 , 24
Operational and Policy Challenges
Four interrelated barriers repeatedly constrained WASH stabilization: insecurity and threats to workers and assets; access restrictions and supply-chain disruption; electricity and fuel dependency; and chronic underfunding with coordination challenges. Their interaction can turn localized, technically manageable failures into prolonged service interruptions.Reference Talhami and Zeitoun 1
Insecurity affects both WASH infrastructure and the personnel needed to operate and repair it. OCHA reported that, during March 16-29, 2025, an incident involving a clearly marked sewage truck in Gaza resulted in the deaths of three municipal sanitation staff, illustrating how routine WASH operations can expose personnel to serious safety risks. 8 When WASH staff cannot safely repair pipelines, pumps, sewage trucks, and sewer lines, localized failures can persist and expand into wider service outages.
This personnel-safety pathway is one form of a broader operational problem seen across the selected settings. In Syria, the pattern was less acute than Gaza’s high-intensity collapse but still reflected prolonged WASH attrition through repeated infrastructure damage, electricity shortages affecting pumping capacity, restricted maintenance, depletion of spare parts, and gradual loss of service functionality. 40 – 41 By 2021, the conflict had left two-thirds of treatment plants out of service and reduced freshwater availability by approximately 40%. 42 Taken together, Gaza, Syria, and Yemen show that although the pathways to WASH collapse differ, the outcome is similar: reduced capacity for water treatment, wastewater management, and distribution, with major public health consequences.
Restrictions on critical WASH inputs limit both water safety and surveillance. In Gaza, these restrictions include controls and delays affecting the entry or movement of chlorination supplies, spare parts, generators, tires, laboratory equipment, and other repair materials needed to operate water, wastewater, and solid-waste services. 8 , 21 WHO noted that restricted entry of chlorination supplies undermined household and system-level disinfection and was associated with diarrheal disease surges. 21 OCHA similarly identified generators, spare parts, chemicals, and equipment as essential WASH items whose restricted or delayed entry impeded water, sewage, and solid-waste management. 8 At the policy level, these barriers reflect more than logistical scarcity; they are shaped by access procedures, security restrictions, administrative approvals, contested governance, and fragmented authority over water and sanitation assets.Reference Al-Saidi, Roach and Al-Saeedi 2 , 8 , Reference Tarnas, Karah and Almhawish 29 Syria illustrates the same policy-level mechanism in a different form: cholera dynamics there have been analyzed as shaped not only by technical WASH deficits, but also by politicization of water, constraints on humanitarian response, and weaknesses in surveillance coordination.Reference Alhaffar, Moreno Gomez and Sigua 10 , Reference Tarnas, Karah and Almhawish 29
Humanitarian and non-governmental organizations often serve as operational intermediaries between disrupted WASH systems and affected communities, particularly where public service capacity is constrained or humanitarian response is delivered substantially through external organizations. Their ability to maintain access, support emergency repairs, sustain water trucking, and document field conditions can influence both service continuity and outbreak detection. At the same time, restrictions on humanitarian access can reduce not only service delivery but also the field-based evidence on which public health assessments depend. 40
Community and System-Level Responses
Across the region, communities and local institutions used water trucking, household storage, private desalination, and improvised sanitation to compensate for service loss.Reference Al-Saidi, Roach and Al-Saeedi 2 , Reference Lane and Kumpel 43 These measures demonstrate local agency and can reduce immediate hardship, but their limited scale, variable safety, and dependence on fuel, chemicals, transport, and household resources prevent them from substituting for system restoration. In Gaza, UNICEF reported large-scale water trucking, support to private desalination plants, and sanitation rehabilitation in shelters and schools. 19 OCHA’s reporting shows how the last mile of water access shifted from networks to logistics, creating equity and protection risks at crowded distribution points. 8 , Reference Lane and Kumpel 43
In cholera-affected settings such as Lebanon and Yemen, outbreak-control experiences highlight the value of multisectoral action, community engagement, and rapid response mechanisms, but they also show that these gains may remain unstable when underlying water and sanitation services remain degraded.Reference Abiad, Abubakar and Hilal 11 However, resilience has limits. Water trucking, household storage, and informal sanitation can reduce immediate suffering, yet they can also introduce secondary risks: inconsistent chlorination, contamination during storage, unaffordable water purchase, and inadequate fecal sludge management.Reference Lane and Kumpel 43 –Reference Li, Li and Saingam 44 At the system level, reliance on emergency modalities can normalize a lower standard of service and delay investments in conflict-resilient infrastructure and governance, particularly when severe and prolonged access constraints persist. 8
Discussion and Preparedness Implications
This review advances the existing literature by moving from country-specific description to a cross-setting explanation of how different conflict conditions converge on WASH-related health risks. Table 2 translates the recurring mechanisms into phased responsibilities for governments, humanitarian organizations, and health care systems. Given the observational and uneven evidence, the framework presents plausible mechanisms rather than causal effect estimates.
Phased preparedness framework for conflict-related WASH system failure
Table 2. Long description
The framework has three phases. Immediate priorities, 0-3 months: protect WASH workers and assets, preserve fuel, electricity, chlorination, spare parts, and emergency water, and jointly monitor WASH and health signals. Governments should secure access and prioritize inputs; humanitarian organizations should pre-position supplies and support emergency services; health care systems should maintain backup water and energy and trigger IPC and outbreak response. Medium-term recovery, 3-24 months: repair water, wastewater, waste, and facility WASH systems; restore laboratories and workforce capacity; stabilize coordination and financing. Long-term resilience, over 24 months: build decentralized and redundant systems, diversify energy, and institutionalize risk-informed governance, community participation, and accountable financing. Health systems should embed WASH resilience in design, accreditation, continuity planning, and routine quality indicators.
Note: The phases are operational guides and may overlap according to conflict intensity and access. Priorities synthesize the mechanisms and interventions discussed in this review.
Immediate Priorities: Protect Essential Services and Connect WASH With Health Surveillance
The country examples show why WASH indicators need to be part of public health risk monitoring. Cholera re-emergence or spread in Syria and Lebanon, sustained cholera burden in Yemen, repeated diarrheal disease signals in Gaza, and suspected hepatitis A transmission all occurred in contexts of damaged water and sanitation systems, unsafe water access, reduced disinfection capacity, displacement, or service disruption.Reference Abiad, Abubakar and Hilal 11 , 20 – 21 , 28 –Reference Tarnas, Karah and Almhawish 29 , 32 – 34 These findings support the integration of WASH functionality indicators, including water quantity and quality, chlorination continuity, wastewater pumping and treatment, waste collection, and health care facility WASH status, into routine health surveillance and early warning systems. 6 , 13 , 21 , 38 – 39
Medium-Term Recovery: Restore Energy Continuity and Service Capacity
The energy-water nexus creates cascading failures that disable WASH systems even when infrastructure survives physical damage. Gaza’s experience illustrates that water purification, desalination, sewage pumping, and facility hygiene depend on electricity and fuel availability. 13 Syria’s 80% decline in energy production severely constrained water systems, illustrating how energy disruption can impair WASH functionality beyond direct infrastructure damage. 45 Practical options include fuel prioritization protocols for WASH utilities, decentralized solar backup systems for critical facilities, pre-positioned generators, and formal energy-WASH cluster coordination mechanisms. 21
Long-Term Resilience: Protect Systems and Strengthen Cross-Sector Governance
Emergency operations centers should monitor WASH indicators such as water availability, sewage overflow, fuel shortages, and disease trends to guide coordinated response decisions. Security incidents affecting sanitation operations and restrictions on repair access can transform manageable outages into wider service failure. 8 Health and WASH clusters should establish joint operational triggers (for example, diarrhea thresholds prompting WASH scale-up; wastewater overflow prompting shelter relocation and vector control), and donor financing could prioritize “maintenance-of-service” programming, often less visible than trauma care but essential to prevent disease amplification. 32
Preparedness for conflict-related WASH failure also depends on the continuity and coordination of external financing, not only on the total volume of aid mobilized. Major external donors, including the European Union through DG ECHO, support WASH operations across several conflict-affected settings in the region. This highlights the importance of coordinating donor-supported programming, cluster mechanisms, and local authorities while maintaining sufficiently flexible funding to preserve service continuity under conditions of restricted access and political disruption. 46 – 47
Across All Phases: Support Community Participation and Decentralized Safe-Water Access
A further preparedness lesson is the need to integrate communities as active partners in preventing the transmission of WASH-sensitive infectious diseases, including cholera, hepatitis A, and other fecal-oral infections. Effective WASH interventions depend not only on infrastructure and service continuity but also on early and sustained community engagement. 48 This includes the dissemination of context-appropriate WASH messages through community health volunteers, who can support households with practical guidance on safe water use, household storage, sanitation, and hygiene behaviors. 48 – 50 Preparedness should also prioritize decentralized access to disinfected water so that treated water is available at the community level rather than concentrated in distant facilities. When communities are informed, engaged, and supported with nearby safe water options, the risk of WASH-sensitive disease transmission may be reduced, and response measures are more feasible, trusted, and sustainable. 48
Future Research Priorities
Five priorities follow from the evidence gaps identified in this review: (1) develop and validate standardized WASH preparedness indicators linked to public health action thresholds; (2) evaluate the effectiveness, safety, equity, and cost of decentralized and redundant WASH systems; (3) measure threats, injuries, retention, and protection mechanisms affecting WASH workers; (4) test the integration of WASH service-function data into disease surveillance and emergency operations; and (5) conduct implementation research on how preparedness packages perform under insecurity, restricted access, displacement, and fragmented governance. Comparative designs using consistent definitions and reporting periods would improve cross-setting learning.
Limitations
This review draws on a heterogeneous evidence base. Peer-reviewed studies generally provide greater methodological detail but may lag rapidly changing events, while humanitarian and UN reports provide timely operational information but may use varying case definitions, incomplete geographic coverage, and limited external verification. Destroyed surveillance systems, displacement, restricted access, insecurity, and loss of laboratory capacity can lead to underreporting and missing data. Estimates were therefore interpreted according to source type, reporting date, geographic scope, and case definition and were not pooled or treated as directly comparable.
Reporting was uneven across settings, with greater detail for contexts where humanitarian organizations had stronger operational reach. This creates availability bias, while publication and reporting may favor outbreaks, severe disruptions, or accessible locations. Some operational estimates may also be revised as access improves. The absence of duplicate screening, a standardized extraction form, formal risk-of-bias assessment, and evidence grading limits reproducibility. Accordingly, the findings should be interpreted as a triangulated, policy-relevant synthesis of converging signals and plausible mechanisms, not as a definitive epidemiologic account or proof that a specific WASH disruption directly caused an observed health outcome.
Conclusion
Conflict-related WASH system failure is a central public health preparedness concern in the Middle East. Across Gaza and the occupied Palestinian territory, Yemen, Syria, Lebanon, and Iraq, different conflict patterns converged through infrastructure damage, dependence on energy and critical inputs, access constraints, threats to the workforce, and governance and financing weaknesses. These mechanisms were consistently associated with reduced water and sanitation services, conditions favorable to outbreaks, unsafe environmental exposure, and weakened clinical care, although surveillance limitations impede direct causal attribution.
The cross-setting lesson is operational: preparedness should interrupt the failure-to-harm pathway at multiple points. Immediate action should protect workers and assets, maintain fuel, electricity, chemicals, and repair access, and link WASH indicators with health surveillance. Medium-term recovery should restore network and health care facility services, workforce capacity, and coordinated financing. Long-term resilience requires decentralized and redundant systems, community participation, and clear, accountable governance. Treating WASH as core health security infrastructure can reduce preventable risk during conflict and early recovery.
Ethics approval and consent to participate
This article is a narrative review of publicly available literature and reports; therefore, ethical approval and consent to participate were not required.
Data availability statement
Not applicable.
Author contribution
Abdullah Shihab: Conceptualization, methodology, investigation, resources, data curation, formal analysis, project administration, writing—original draft, writing—review and editing; Chiara Cadeddu: Conceptualization, methodology, validation, writing—review and editing; Hiba Mohammad: Investigation, resources, validation, writing—review and editing; Jamla Rizek: Investigation, validation, writing—review and editing; Houssem Eddine Ben-Ahmed: Validation, writing—review and editing; Mohanad Ghaleb: Resources, validation, writing—review and editing; Sadeq AL-Fayyadh: Validation, writing—review and editing.
Funding statement
No external funding was received for the development, conduct, or reporting of this review.
Competing interests
None.
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