Cross Sectional Survey of Parasitic Contamination in Vegetables Consumed in Birjand City in 2024

Background: Vegetables are a staple in diets worldwide, providing essential vitamins for human health. However, throughout the processes of planting, harvesting, and distribution, they are often at risk of contamination from various parasites, increasing the potential for transmission. Objectives: This study aimed to compare the parasitic contamination of different vegetables in the center of South Khorasan province. Methods: In this cross-sectional study, 200 samples of vegetables, including leeks, basil, mint, scallions, radishes, parsley, lettuce, watercress, green almonds, coriander, spinach, tarragon, turnips, and purslane, which are consumed raw by the public, were collected from Birjand city from summer to autumn 2024. Samples of 250 g from each type of vegetable were collected and brought to the laboratory. These samples were dissolved in buckets containing 1 liter of physiological serum, and the sediments were subjected to centrifugation. The supernatant contents were carefully discarded, and the sediments were examined using the laboratory method of direct smear and staining with Lugol's iodine under a microscope with 10× and 40× magnification. Data analysis was performed using IBM SPSS software version 21, employing statistical tests, including Fisher's exact test, at a significance level of P < 0.05. Results: Out of 200 vegetable samples examined, 39% were found to be infected with parasites. The highest rates of parasitic infection were observed in spinach (70%), green almonds (66%), leeks (66%), mint (53%), coriander (44%), lettuce (50%), and purslane (29%). The most frequent parasitic infection was associated with Blastocystis (23.5%), followed by Giardia (2%), nematodes (2%), Dicrocoelium eggs (1.5%), and amoeba cysts (1%). No significant relationship was observed between the frequency of parasitic infection and variables such as season, distribution areas, or breeding places (P > 0.05). However, a significant relationship was observed with the type of vegetables consumed (P < 0.05). Conclusions: Based on the results and the high level of contamination in vegetables, it is essential to implement appropriate disinfection measures before consumption and provide community members in Birjand city with education on proper vegetable handling and hygiene practices.