Toxoplasma gondii in water and food: public health concerns in Europe
DOI:
https://doi.org/10.4321/s2173-92772026000300012Keywords:
Toxoplasma gondii, food and waterborne zoonosis, sources, risk factors, knowledge gapsAbstract
Toxoplasma gondii is considered a major zoonotic agent; its varied and effective modes of transmission and spread explain, among other factors, why 32% of the European human population is infected with the parasite, with even higher rates observed in livestock and game animals. Human infection has multiple sources, including undercooked meat and meat products that may contain viable tissue cysts; unpasteurized goat’s milk, which may contain tachyzoites; and untreated water, unwashed fresh vegetables, and fresh, unpurified bivalve mollusks, among others, which may harbor oocysts of the parasite. Currently, the exact proportion to which different modes of transmission contribute to human infections is unknown, and the available studies on risk factors are mostly outdated. This article aims to provide a critical analysis of the current information available and existing knowledge gaps regarding food- and water-borne sources of T. gondii infection in humans and suggesting potential approaches that will provide accurate information for assessing the risk of human infections on the European population.
Downloads
References
Calero-Bernal R, Gennari SM, Cano S, Salas-Fajardo MY, Ríos A, Álvarez-García G, Ortega-Mora LM. Anti-Toxoplasma gondii Antibodies in European Residents: A Systematic Review and Meta-Analysis of Studies Published between 2000 and 2020. Pathogens. 2023;12(12):1430. doi: 10.3390/pathogens12121430.
Friesema IH, Waap H, Swart A, Györke A, Le Roux D, Evangelista FM, Spano F, Schares G, Deksne G, Gargaté MJ, Calero-Bernal R, Jokelainen P, Seeber F, Sroka J, Lundén A, van den Berg O, Jore S, Wisselink HJ, Dámek F, Vestergaard LS, Opsteegh M. Systematic review and modelling of Toxoplasma gondii seroprevalence in humans, Europe, 2000 to 2021. Euro Surveill. 2025;30(34):2500069. doi: 10.2807/1560-7917.ES.2025.30.34.2500069.
Almeria S, Dubey JP. Foodborne transmission of Toxoplasma gondii infection in the last decade. An overview. Res Vet Sci. 2021;135:371-85. doi: 10.1016/j.rvsc.2020.10.019.
Milne GC, Webster JP, Walker M. Is the incidence of congenital toxoplasmosis declining? Trends Parasitol. 2023;39(1):26-37. doi: 10.1016/j.pt.2022.10.003.
Robertson LJ, Minato Y, Devleesschauwer B, Di Bari C, Vaes L, Keddy KH, Sripa B, Fernandez K, Pires SM, Majowicz SE, Lake RJ, Roberts C, Nane GF, Kretzschmar ME, Mughini-Gras L, Rostami A, Carabin H, Budke CM, Donadeu M, Torgerson PR; WHO Foodborne Disease Burden Epidemiology Reference Group for 2021–25. WHO estimates of the global, regional, and national foodborne burdens of 14 invasive parasitic diseases, 2000-21: an updated data synthesis. Lancet Glob Health. 2026;14(8):103982. doi: 10.1016/j.langlo.2026.103982.
European Food Safety Authority (EFSA) | European Centre for Disease Prevention and Control (ECDC). The European Union One Health 2024 Zoonoses Report. EFSA J. 2025;23(12):e9759. doi: 10.2903/j.efsa.2025.9759.
Dubey JP. Toxoplasmosis of Animals and Humans. 3rd ed. Boca Ratón: CRC Press; 2021b. 564 p. doi: 10.1201/9781003199373
Giese L, Seeber F, Aebischer A, Kuhnert R, Schlaud M, Stark K, Wilking H. Toxoplasma gondii Infections and Associated Factors in Female Children and Adolescents, Germany. Emerg Infect Dis. 2024;30(5):995-9. doi: 10.3201/eid3005.231045.
López-Ureña NM, Calero-Bernal R, Koudela B, Cherchi S, Possenti A, Tosini F, Klein S, San Juan-Casero C, Jara-Herrera S, Jokelainen P, Regidor-Cerrillo J, Ortega-Mora LM, Spano F, Seeber F, Álvarez-García G. Limited value of current and new in silico predicted oocyst-specific proteins of Toxoplasma gondii for source-attributing serology. Front Parasitol. 2023;2:1292322. doi: 10.3389/fpara.2023.1292322.
Meireles LR, Ekman CCJ, Andrade Jr HF, Luna EJA. (2015). Human toxoplasmosis outbreaks and the agent infecting form. Findings from a systematic review. Rev. Inst. Med. Trop. Sao Paulo. 2015;57(5):369-76. doi: 10.1590/S0036-46652015000500001
Reyes-Toledo R, Culma-Roa L, López MJ, Pérez JE, Suárez-Silva D. Outbreak of toxoplasmosis with pulmonary involvement in immunocompetent military population. Biomedica. 2026;46(1):9-17. doi: 10.7705/biomedica.7728.
López-Ureña, NM (2024) Detección de Toxoplasma gondii en productos frescos y desarrollo de nuevos métodos serológicos que permitan determinar el origen de la infección. Tesis Doctoral. Universidad Complutense de Madrid.
Dubey JP. Outbreaks of clinical toxoplasmosis in humans: five decades of personal experience, perspectives and lessons learned. Parasit Vectors. 2021a;14(1):263. doi: 10.1186/s13071-021-04769-4.
Pinto-Ferreira F, Caldart ET, Pasquali AKS, Mitsuka-Breganó R, Freire RL, Navarro IT. Patterns of Transmission and Sources of Infection in Outbreaks of Human Toxoplasmosis. Emerg Infect Dis. 2019;25(12):2177-82. doi: 10.3201/eid2512.181565.
Guo M, Dubey JP, Hill D, Buchanan RL, Gamble HR, Jones JL, Pradhan AK. Prevalence and risk factors for Toxoplasma gondii infection in meat animals and meat products destined for human consumption. J Food Prot. 2015;78(2):457-76. doi: 10.4315/0362-028X.JFP-14-328.
Cook AJ, Gilbert RE, Buffolano W, Zufferey J, Petersen E, Jenum PA, Foulon W, Semprini AE, Dunn DT. Sources of Toxoplasma infection in pregnant women: European multicentre case-control study. European Research Network on Congenital Toxoplasmosis. BMJ. 2000;321(7254):142-7. doi: 10.1136/bmj.321.7254.142.
Belluco S, Simonato G, Mancin M, Pietrobelli M, Ricci A. Toxoplasma gondii infection and food consumption: A systematic review and meta-analysis of case-controlled studies. Crit Rev Food Sci Nutr. 2018;58(18):3085-96. doi: 10.1080/10408398.2017.1352563.
Friesema IHM, Hofhuis A, Hoek-van Deursen D, Jansz AR, Ott A, van Hellemond JJ, van der Giessen J, Kortbeek LM, Opsteegh M. Risk factors for acute toxoplasmosis in the Netherlands. Epidemiol Infect. 2023;151:e95. doi: 10.1017/S0950268823000808.
Thebault, A.; Kooh, P.; Cadavez, V.; Gonzales-Barron, U.; Villena, I. Risk Factors for Sporadic Toxoplasmosis: A Systematic Review and Meta-Analysis. Microb. Risk Anal. 2021;17:100133. doi: 10.1016/j.mran.2020.100133.
Wilking H, Thamm M, Stark K, Aebischer T, Seeber F. Prevalence, incidence estimations, and risk factors of Toxoplasma gondii infection in Germany: a representative, cross-sectional, serological study. Sci Rep. 2016;6:22551. doi: 10.1038/srep22551.
Stelzer S, Basso W, Benavides Silván J, Ortega-Mora LM, Maksimov P, Gethmann J, Conraths FJ, Schares G. Toxoplasma gondii infection and toxoplasmosis in farm animals: Risk factors and economic impact. Food Waterborne Parasitol. 2019;15:e00037. doi: 10.1016/j.fawpar.2019.e00037.
González-Barrio D, Carpio AJ, Preite L, Miguel-Vicedo M, Estévez-Reboredo RM, González-Viadero M, Barba-Sánchez R, Calero-Bernal R, Carmena D, Fuentes I. Toxoplasma gondii exposure in wildlife in Spain: Is there any predictable threat for humans and domestic animals? Sci Total Environ. 2024;935:173290. doi: 10.1016/j.scitotenv.2024.173290.
Ducrocq J, Simon A, Lemire M, De Serres G, Lévesque B. Exposure to Toxoplasma gondii Through Consumption of Raw or Undercooked Meat: A Systematic Review and Meta-Analysis. Vector Borne Zoonotic Dis. 2021;21(1):40-9. doi: 10.1089/vbz.2020.2639.
Moreno-Mesonero L, Soler L, Amorós I, Moreno Y, Ferrús MA, Alonso JL. Protozoan parasites and free-living amoebae contamination in organic leafy green vegetables and strawberries from Spain. Food Waterborne Parasitol. 2023;32:e00200. doi: 10.1016/j.fawpar.2023.e00200.
Blanda V, Giacchino I, Vaglica V, Milioto V, Migliore S, Di Bella S, Gucciardi F, Bongiorno C, Chiarenza G, Cardamone C, Mancuso I, Scatassa ML, Cannella V, Guercio A, Purpari G, Grippi F. Foodborne Pathogens Across Different Food Matrices in Sicily (Southern Italy). Pathogens. 2024;13(11):998. doi: 10.3390/pathogens13110998.
Calero-Bernal R, Betson M, Slana I, Bartosova B, Marucci G, Possenti A, Álvarez-García G, Bier N, Mayer-Scholl A, Berg RP, Chaudhry U, López-Ureña NM, Piotrowska W, Sroka J, Johannessen GS, Davidson R, Dámek F, Blaga R, Thoumire S, Zalewská B, Waap HC, Jokelainen P, Lalle M. Molecular detection of Toxoplasma gondii in ready-to-eat salad mixes: multi-country survey using a validated and harmonised standard operating procedure, Europe, 2021 to 2022. Euro Surveill. 2025;30(22):2400594. doi: 10.2807/1560-7917.ES.2025.30.22.2400594.
Boughattas S. Toxoplasma infection and milk consumption: Meta-analysis of assumptions and evidences. Crit Rev Food Sci Nutr. 2017;57(13):2924-33. doi: 10.1080/10408398.2015.1084993.
Deng H, Exel KE, Swart A, Bonačić Marinović AA, Dam-Deisz C, van der Giessen JWB, Opsteegh M. Digging into Toxoplasma gondii infections via soil: A quantitative microbial risk assessment approach. Sci Total Environ. 2021;755(Pt 2):143232. doi: 10.1016/j.scitotenv.2020.143232.
Olsen A, Swart A, Pires SM, Fagt S, Møgelmose V, Houe H, Denwood M, Nielsen HV, Alban L. Tissue cyst-based quantitative risk assessment of human toxoplasmosis from consuming pork in Denmark: A farm-to-fork approach. Prev Vet Med. 2025;238:106446. doi: 10.1016/j.prevetmed.2025.106446.
Downloads
Published
Issue
Section
License
Copyright (c) 2026 Rafael Calero-Bernal, Gema Álvarez-García, Luis Miguel Ortega-Mora

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
El material creado por un autor puede ser distribuido, copiado y exhibido por terceros si se hace referencia a la autoría. No se puede obtener ningún beneficio comercial y las obras derivadas tienen que estar bajo los mismos términos de licencia que el trabajo original


