Parasitic contamination of raw vegetables in Iran: A systematic review and meta-analysis

Green leafy vegetables make up a large portion of the vitamins and minerals for human body. This study aims to estimate the prevalence of contamination of vegetables to different parasite stages in Iran by conducting a systematic review and meta-analysis. Multiple keywords such as vegetables, parasitic contamination, intestinal parasites and Iran used to search in SID, Magiran, Pubmed, Iranmedex, Irandoc and ISI databases. A total of 43 articles found, of which, eight articles did not have enough information and full text of 14 articles was not available. Finally, 21 studies entered in meta-analysis process. Variance of each study obtained using binomial distribution. Heterogeneity between studies checked using Cochran's Q Test. Random Effects Model was used to pool the prevalence of parasitic contamination and intestinal parasites in the studies. Among 4359 samples the overall prevalence was estimated results of 37 for parasitic contamination of vegetables in Iran. Vegetables: Scallion, Leek, Basil, Radish, Tarragon, Parsley, Lettuce, Coriander, Spearmint and Garden crest have been studied and parasites: Eggs of Toxocara sp. (75), Dicrocoelium dendriticum (39), Hymenolepis nana (39), Hymenolepis diminuta (15), Fasciola sp. (44), Taenia spp. (26), Trichocephal (50), Trichostrongylus (25), Ascaris (28) and cyst of Entamoeba coli (47), Entamoeba histolytica (25), chilomastix mesnili (22) and Giardia lamblia (43) isolated from vegetables. Highest intensity of contamination (46) was related to scallion. It may be concluded, despite the relative improvement of sanitary, economic, social and agricultural conditions, the parasites are common in vegetables that are frequently eaten. It is necessary to improve the public health and training methods for washing vegetables.