Intestinal Parasites in Raw Vegetables and Khat (Catha edulis) Sold in Aden, Yemen: A Market-Based Cross-Sectional Study

Background: Raw vegetables and khat (Catha edulis) are consumed without a kill step and can carry intestinal parasites along the farm-to-fork chain. Up-to-date, market-level data from Aden are limited, particularly for khat. Methods: A descriptive cross-sectional survey (July–October 2023) sampled 226 retail items from Aden: 136 vegetables (15 commodities) and 90 khat bundles (10 named types from five markets). Each sample was washed in saline, sediments concentrated by settling and centrifugation, and modified Ziehl–Neelsen staining was used for coccidia and zinc sulfate flotation when indicated. Results: Overall contamination was 48.5% in vegetables (66/136) and 34.4% in khat (31/90). In vegetables, protozoa predominated: Entamoeba histolytica/dispar 36.8% (50/136) and Giardia lamblia 21.3% (29/136); helminths were led by Ascaris lumbricoides 19.9% (27/136), with Trichuris trichiura 8.8%, Taenia spp. 6.6%, Strongyloides stercoralis 4.4%, and Cryptosporidium spp. 5.1%. Within-commodity positivity was highest in coriander, 77.8% (7/9), green chili, 66.7% (6/9), and watercress, 60.0% (6/10). In khat, detections included E. histolytica/dispar 23.3% (21/90), G. lamblia 10.0% (9/90), A. lumbricoides 10.0% (9/90), and 2.2% each for Taenia spp. and Cryptosporidium spp. Market-level khat positivity ranged from 16.7% to 44.4% across sites. Conclusion: Market-sold vegetables and khat in Aden frequently harbored intestinal parasites, with the highest burdens in leafy or finely textured items and measurable variation by khat market. Findings support practical controls—safer irrigation and wash water, hygienic retail handling, and consumer washing guidance—and provide a baseline for seasonal surveillance and method-enhanced confirmation (e.g., antigen/PCR) in this setting.