Parasitic Contamination of Commonly Consumed and Locally Cultivated Leafy Vegetables in Jos, North-Central Nigeria

Contamination of vegetables remains important for transmitting intestinal parasites in developing countries. This study aimed to investigate the types and levels of parasitic contamination of six commonly consumed vegetables in Jos, Nigeria.

Leafy vegetables (cabbage, African spinach, spring onion, lettuce, fluted pumpkin leaf, and sorrel leaf) were purchased from five central markets in Jos, from September 2020 to February 2021. Samples were rinsed in sterile water, 0.9% saline, 1.5% saline, and vinegar (containing 1.7% acetic acid) and then processed using sedimentation concentration technique. Sediments were examined using direct wet preparation.

Overall prevalence of parasitic contamination was 75.9% (n = 270). African spinach recorded the highest contamination (91.1%), followed by lettuce (86.7%), while spring onion had  the least contamination. Sixteen helminths and 4 protozoans were identified. Taenia species had the highest prevalence (33.9%), followed by Entamoeba histolytica (28.5%). Schistosoma haematobium had the least prevalence. Parasitic contamination was significantly different among markets and vegetable types (P<0.05). Preliminary findings revealed that 1.5% saline rinse generally resulted in the highest parasite detection rates.

Findings revealed a high burden of parasitic contamination of leafy vegetables in Jos, Nigeria. Public enlightenment on proper handling and processing of vegetables, from farm to table, is recommended.