Occurrence of Toxoplasma gondii on Raw Leafy Vegetables in Gaza, Palestine

Parasitic contamination in green vegetables from open markets in Gampaha District, Sri Lanka: Implications for human health

Intestinal parasitic infections in Sri Lanka have received little attention due to their perceived low prevalence. Consuming raw vegetables without proper washing is one of the main ways to transmit intestinal parasitic infections. Therefore, this study investigated the contamination of parasites in vegetables. A cross-sectional study was conducted from August 2023 to January 2024 at fifty selected open markets in ten cities (Ragama, Miriswatta, Kirillawala, Kadawatha, Balummahara, Kiribathgoda, Peliyagoda, Weliweriya, Imbulgoda and Gampaha) in Gampaha District, Sri Lanka. Four vegetable types, namely Centella asiatica (Gatu kola) [n = 162], Ipomoea aquatica (Kankun) [n = 150], Alternanthera sessilis (Mukunuwenna) [n = 160] and Lactuca sativa (Lettuce) [n = 148] that are consumed either raw or half cooked were selected. Approximately 50 g of each vegetable was taken randomly at each sampling attempt. Each sample was dipped in the Tween 20 (5%) in a shaker for 15 minutes, followed by sedimentation overnight and centrifugation (2000 × g for 15 min). Both supernatant and sediment were examined under a light microscope to detect parasitic stages. The overall prevalence of parasitic contamination in the samples was 21.29% (n = 132). Centella asiatica indicated the highest contamination (37.65% [61/162]). Lactuca sativa had the lowest contamination (2.02% [3/148]). Parasites including protozoan (Entamoeba histolytica, Giardia lamblia, Toxoplasma gondii, Blastocystis hominis, Paramphistomum spp and Balantidium coli) and helminths (Ascaris spp., Hymenolepis spp., Strongyloides stercoralis, Trichuris spp, Taenia spp, Toxocara canis and hookworms) were detected. Blastocystis hominis was the most predominant (4.68%; n = 29). Toxocara sp, G. lamblia and Eimeria sp were identified as least abundant (0.77%; n = 5). Every sample contained at least one parasitic contamination. A significant difference between the type of vegetables and the existence of parasites was identified (P = 0.008). The parasitic stages identified could cause infections among people with poor food hygienic/ preparation practices. Therefore, health authorities must educate consumers on precautionary measures to prevent re-emerging intestinal parasitic infections in Sri Lanka.

Toxoplasma Gondii in humans, animals and in the environment in Morocco: a literature review

Toxoplasmosis, caused by Toxoplasma gondii, has the unsettling ability to infect nearly every warm-blooded vertebrate. When transmitted from mother to fetus during pregnancy, it can lead to congenital toxoplasmosis in newborns, which may have severe and even fatal outcomes. Moreover, this parasite is a significant cause of reproductive issues in cattle. The aim of this literature review was to compile and synthesize information on the epidemiology and clinical features of naturally occurring Toxoplasma gondii infections in both humans and animals, as well as to assess the occurrence of oocysts in the environmental matrices in Morocco. To achieve these objectives, data were sourced from four electronic databases: PubMed, Web of Science, Scopus, and Google Scholar. A total of 32 articles published between January 1, 2000, and January 31, 2024, met the inclusion criteria. The findings indicated that the seroprevalence of T. gondii among pregnant women varied by city and appeared to be lower in drier climates. The study identified several risk factors associated with T. gondii infection among women in Morocco, including direct contact with soil, failure to wash fruits and vegetables before eating, limited education, and reliance on well water for drinking. Moreover, there is a limited amount of serological data on T. gondii in animals. In Morocco, the prevalence of this parasite can reach up to 30% in sheep, while it stands at 8.5% in cattle and goats. Leafy greens are particularly prone to hosting pathogens and are associated with foodborne outbreaks. In Morocco, the prevalence of T. gondii in leafy vegetables is around 16%, although soil analyses have not found any oocysts. This review offers a thorough epidemiological overview of T. gondii infections in Morocco, serving as a valuable resource for researchers and aiding in the development of control and prevention programs.

First report demonstrating the presence of Toxocara spp. eggs on vegetables grown in community gardens in Europe

Toxocara canis and T. cati are zoonotic roundworm parasites of dogs, cats and foxes. These definitive hosts pass eggs in their faeces, which contaminate the environment and can subsequently be ingested via soil or contaminated vegetables. In humans, infection with Toxocara can have serious health implications. This proof-of-concept study aimed to investigate the presence of Toxocara spp. eggs on ‘ready-to-eat’ vegetables (lettuce, spinach, spring onion and celery) sampled from community gardens in southern England. The contamination of vegetables with Toxocara eggs has never been investigated in the UK before, and more widely, this is the first time vegetables grown in community gardens in Europe have been assessed for Toxocara egg contamination. Sixteen community gardens participated in the study, providing 82 vegetable samples fit for analysis. Study participants also completed an anonymous questionnaire on observed visits to the sites by definitive hosts of Toxocara. Comparison of egg recovery methods was performed using lettuce samples spiked with a series of Toxocara spp. egg concentrations, with sedimentation and centrifugal concentration retrieving the highest number of eggs. A sample (100 g) of each vegetable type obtained from participating community gardens was tested for the presence of Toxocara eggs using the optimised method. Two lettuce samples tested positive for Toxocara spp. eggs, giving a prevalence of 2.4% (95% CI =1.3–3.5%) for vegetable samples overall, and 6.5% (95% CI = 4.7–8.3%; n = 31) specifically for lettuce. Questionnaire data revealed that foxes, cats and dogs frequently visited the community gardens in the study, with 88% (68/77) of respondents reporting seeing a definitive host species or the faeces of a definitive host at their site. This proof-of-concept study showed for the first time the presence of Toxocara spp. eggs on vegetables grown in the UK, as well as within the soil where these vegetables originated, and highlights biosecurity and zoonotic risks in community gardens. This study establishes a method for assessment of Toxocara spp. eggs on vegetable produce and paves the way for larger-scale investigations of Toxocara spp. egg contamination on field-grown vegetables.

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First report of Toxocara eggs on vegetables grown in community gardens in Europe.

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Toxocara also detected in the soil where these vegetables originated.

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Definitive hosts for Toxocara canis and T. cati frequently visit community gardens.

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Sedimentation method recovered the most Toxocara eggs from spiked lettuce samples.

Contamination of Soil, Water, Fresh Produce, and Bivalve Mollusks with Toxoplasma gondii Oocysts: A Systematic Review

Toxoplasma gondii is a major foodborne pathogen capable of infecting all warm-blooded animals, including humans. Although oocyst-associated toxoplasmosis outbreaks have been documented, the relevance of the environmental transmission route remains poorly investigated. Thus, we carried out an extensive systematic review on T. gondii oocyst contamination of soil, water, fresh produce, and mollusk bivalves, following the PRISMA guidelines. Studies published up to the end of 2020 were searched for in public databases and screened. The reference sections of the selected articles were examined to identify additional studies. A total of 102 out of 3201 articles were selected: 34 articles focused on soil, 40 focused on water, 23 focused on fresh produce (vegetables/fruits), and 21 focused on bivalve mollusks. Toxoplasma gondii oocysts were found in all matrices worldwide, with detection rates ranging from 0.09% (1/1109) to 100% (8/8) using bioassay or PCR-based detection methods. There was a high heterogeneity (I2 = 98.9%), which was influenced by both the sampling strategy (e.g., sampling site and sample type, sample composition, sample origin, season, number of samples, cat presence) and methodology (recovery and detection methods). Harmonized approaches are needed for the detection of T. gondii in different environmental matrices in order to obtain robust and comparable results.