https://doi.org/10.4081/ijfs.2026.15114
Current research trends towards the control of protozoans in foods
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Published: 25 March 2026
Protozoan parasites such as Cryptosporidium spp., Giardia duodenalis, Toxoplasma gondii and Cyclospora cayetanensis remain difficult-to-control hazards in food due to environmental persistence, low infectious doses, and the interpretability gap between nucleic acid detection and infectivity. This review synthesizes 4-year research trends shaping protozoan control in food systems, focusing on three critical pillars: matrix-adapted front-end processing (concentration, lysis, inhibitor management); inhibitor-resilient quantification; and sequencing-based attribution for outbreak investigation and source tracking. Recent benchmarking across wastewater, the water–soil–produce nexus, and food-relevant matrices repeatedly indicates – depending on matrix and study design – that upstream workflow steps often dominate analytical sensitivity and reproducibility. Accordingly, tiered analytical strategies are emerging in which the quantitative polymerase chain reaction (PCR) technique supports scalable screening, droplet digital PCR is used for decision-grade confirmation/quantification under inhibition and low-template conditions, and targeted sequencing or metagenomics is deployed selectively for traceback and contextual investigation. We integrate these developments into an actionable control framework that links prevention at the water–soil–plant interface with tiered analytics and viability-aware interpretation of post-intervention results. Research priorities ahead include harmonized performance reporting (recovery, inhibition controls, limit of detection/quantification), transparent endpoint hierarchy for intervention claims (detectability versus viability/infectivity), and interoperable sequence databases to enable cross-laboratory attribution and program-level learning. The field is moving from “can we detect?” towards “can we decide? – requiring reproducible front-end processing, inhibitor-resilient quantification, interoperable attribution resources, and endpoint discipline for intervention efficacy claims.
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CRediT authorship contribution
Mariem Ayed: data collection, data curation, analysis & interpretation of data, writing - original draft, writing - review and editing. Vasco Cadavez, Ursula Gonzales-Barron: conceptualization and study design, data collection, data curation, analysis and interpretation of data, writing - review and editing, supervision, project administration and funding acquisition. All the authors read and approved the final version of the manuscript and agreed to be accountable for all aspects of the work.
Supporting Agencies
This work was funded by the European Food Safety Authority (EFSA) through GP/EFSA/BIOHAW/2022/01 and GP/EFSA/BIOHAW/2023/05; and was also supported by national funds through FCT/MCTES (PIDDAC): CIMO UID/00690/2025 (10.54499/UID/00690/2025) and UID/PRR/00690/2025 (10.54499/UID/PRR/00690/2025); SusTEC, LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020).How to Cite
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