Giardia and Campylobacter: Fifteen years (2010-2024) of waterborne outbreaks in Europe

Waterborne diseases affect millions of people annually, challenging public health worldwide. Despite the advancements in water management, high-income countries remain at risk, mainly because of faulty or ageing water infrastructure. Giardia and Campylobacter are two key waterborne pathogens and leading agents of gastrointestinal illnesses. Both can be transmitted through contaminated water under similar environmental and sanitary conditions, with co-infections worsening symptoms and complicating diagnosis and treatment efficacy. This review examines waterborne outbreaks in Europe, over the last 15 years (2010–2024), focusing on Giardia while adding an additional perspective on Campylobacter . Over 30 outbreaks were reported during the study period, primarily in Ireland and Nordic countries. Recreational and drinking water sources were the most commonly implicated, with contamination events often associated with specific incidents or treatment failures, and heavy rainfall suggested as contributing factor to pathogen entry. In addition, climate change is discussed as a major driver exacerbating waterborne disease risks through extreme weather events. The review highlights persistent vulnerabilities in water safety across Europe, and emphasizes the importance of mitigation strategies, which include risk assessment, early detection and continuous surveillance, improved water treatment and climate-resilient infrastructures, along with interdisciplinary collaboration with different stakeholders.