Original Article

The Influence of Selected Factors on the Detection of Giardia intestinalis by Microscopic and Immunoenzymatic Methods


Background: Giardia intestinalis is one of the most common parasites in humans. Contaminated food and water can be a source of infection. Substances added to food are intended to increase its safety. We aimed to determination of the influence of various microorganisms and compounds that stimulate digestive functions, as well as preservatives and antioxidants on the detection of G. intestinalis by microscopic and immunoenzymatic methods.

Methods: Twenty stool samples, archived in 1998-2018 in the Provincial Sanitary and Epidemiological Station in Bydgoszcz (Poland), collected both from patients referred for parasitic examinations by a doctor of a medical facility and from private individuals, were used to assess the impact of selected factors (such as bacterial strains, viruses and substances added to food) on the detection of G. intestinalis by microscopic and immunoenzymatic methods.

Results: G. intestinalis was detected by both microscopic and immunoenzymatic methods with the same sensitivity (100%). The result of the G. intestinalis determination was positive in 90% of the samples after the addition of potassium sorbate, and in 25% of the samples after the addition of citric acid.

Conclusion: The presence of other microorganism such as bacteria and viruses does not influence on the detection of G. intestinalis by microscopic and immunoenzymatic methods in stool samples. Citric acid as an antioxidant added to foods affects the detection of G. intestinalis. Due to the small number of samples used, it is necessary to continue research on the impact of various factors on the detection of protozoa.

1. Halliez MC, Buret AG. Extra-intestinal and long term consequences of Giardia duode-nalis infections. World J Gastroenterol. 2013 Dec 21;19(47):8974-85. doi: 10.3748/wjg.v19.i47.8974.
2. Rossignol JF. Cryptosporidium and Giardia: treatment options and prospects for new drugs. Exp Parasitol. 2010 Jan;124(1):45-53. doi: 10.1016/j.exppara.2009.07.005.
3. Choy S, Al-Mekhlafi H, Mahdy M, et al. Prevalence and Associated Risk Factors of Giardia Infection among Indigenous Communities in Rural Malaysia. Sci Rep. 2014 4:6909. doi: 10.1038/srep06909.
4. Roshidi N, Mohd Hassan NH, Abdul Hadi A, Arifin N. Current state of infec-tion and prevalence of giardiasis in Malay-sia: a review of 20 years of research. Peer J. 2021 Nov 11;9:e12483. doi: 10.7717/peerj.12483.
5. Lee R. Health care problems of lesbian, gay, bisexual, and transgender patients. West J Med. 2000 172 (6): 403-8. doi: 10.1136/ewjm.172.6.403.
6. Franssen F, Gerard C, Cozma-Petruţ A, et al. Inactivation of parasite transmission stages: Efficacy of treatments on food of animal origin. Trends in Food Science & Technology. 2019; 83: 114-128. doi: 10.1016/j.tifs.2018.11.009.
7. Awuchi, CG, Twinomuhwezi, H, Igwe, VS, et. al. Food Additives and Food Preserva-tives for Domestic and Industrial Food Applications. Journal of Animal Health. 2020; 2(1): 1-16.
8. Faustino M, Veiga M, Sousa P, Costa EM, Silva S, Pintado M. Agro-Food Byproducts as a New Source of Natural Food Addi-tives. Molecules. 2019 Mar 18;24(6):1056. doi: 10.3390/molecules24061056.
9. Silva MM, Lidon FC. Food preservatives – An overview on applications and side ef-fects. Emirates Journal of Food and Agriculture. 2016. 28(6): 366-373. doi: 10.9755/ejfa.2016-04-351.
10. Silva MM, Lidon FC. An overview on ap-plications and side effects of antioxidant food additives. Emirates Journal of Food and Agriculture. 2016. 28(12): 823-832. doi: 10.9755/ejfa.2016-07-806.
11. Saltmarsh M, Chapter 1:Food Additives and Why They Are Used, in Saltmarsh's Essential Guide to Food Additives (5), 2020, 1-9. doi: 10.1039/9781839161063-00001.
12. Rogawski ET, Bartelt LA, Platts-Mills JA, et al. Determinants and Impact of Giardia Infection in the First 2 Years of Life in the MAL-ED Birth Cohort. J Pediatric Infect Dis Soc. 2017; 6(2):153–60. doi: 10.1093/jpids/piw082.
13. Addiss DG, Mathews HM, Stewart JM, et al. Evaluation of a Commercially Available Enzyme-Linked Immunosorbent Assay for Giardia lamblia Antigen in Stool. J Clin Microbiol. 1991; 29: 1137-1142. doi: 10.1128/jcm.29.6.1137-1142.1991.
14. Zimmerman SK, Needham CA. Compari-son of Conventional Stool Concentration and Preserved-Smear Methods with Meri-fluor Cryptosporidium/Giardia Direct Immu-nofluorescence Assay and ProSpecT Giar-dia EZ Microplate Assay for Detection of Giardia lamblia. J Clin Microbiol. 1995; 33: 1942–1943. doi: 10.1128/jcm.33.7.1942-1943.1995.
15. Janoff EN, Craft JC, Pickering LK, et al. Diagnosis of Giardia lamblia Infections by Detection of Parasite-Specific Antigens. J Clin Microbiol. 1989; 27: 431-435. doi: 10.1128/jcm.27.3.431-435.1989.
16. El-Nahas, HA, Salem DA, El-Henawy AA, et al. Giardia Diagnostic Methods in Hu-man Fecal Samples: A Comparative Study. Cytometry B Clin Cytom. 2013; 84B:44–49. doi: 10.1002/cyto.b.21048.
17. Behr MA, Kokoskin E, Gyorkos TW, et al. Laboratory diagnosis for Giardia lamblia infection: A comparison of microscopy, coprodiagnosis and serology. Can J Infect Dis. 1996; 8(1):33-38. doi: 10.1155/1997/270179.
18. Alles AJ, Waldron MA, Sierra LS, et al. Prospective Comparison of Direct Immu-nofluorescence and Conventional Staining Methods for Detection of Giardia and Cryptosporidium spp. in Human Fecal Spec-imens. J Clin Microbiol. 1995; 33: 1632–1634. doi: 10.1128/jcm.33.6.1632-1634.1995.
19. Al-Nabulsi AA, Olaimat AN, Osaili TM, et al. Use of acetic and citric acids to control Salmonella Typhimurium in tahini (sesame paste). Food Microbiol. 2014; 42, 102–108. doi: 10.1016/j.fm.2014.02.020.
20. Bermúdez-Aguirre D, Barbosa-Cánovas GV. Disinfection of selected vegetables under nonthermal treatments: Chlorine, acid citric, ultraviolet light and ozone. Food Control. 2013; 29(1), 82–90. doi: 10.1016/j.foodcont.2012.05.073.
IssueVol 18 No 1 (2023) QRcode
SectionOriginal Article(s)
Food additives Giardia intestinalis Immunoenzymatic method Microscopic method

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How to Cite
Smoguła M, Mila-Kierzenkowska C, Szewczyk-Golec K. The Influence of Selected Factors on the Detection of Giardia intestinalis by Microscopic and Immunoenzymatic Methods. Iran J Parasitol. 2023;18(1):30-37.