Prevalence of Intestinal Protozoan Parasites Among Food Handlers in Iran: A Systematic Review and Meta‑Analysis
Main Article Content
Abstract
Background: Intestinal protozoa are significant causes of foodborne diseases in food handlers who may also act as carriers of no signs of infection. Food handling is an important occupation in Iran; although a national estimate of intestinal protozoan prevalence has been previously reported, it is now outdated and more recent data is required. Therefore, we aimed to determine the pooled prevalence of intestinal protozoan parasites and examine geographic variation among food handlers in Iran.
Methods: A systematic literature search was conducted using PubMed, Scopus, Embase, Web of Science, and Google Scholar up to 2025. Cross‑sectional studies reporting the prevalence of intestinal protozoa among Iranian food handlers were included. Pooled prevalence with 95% confidence intervals (CIs) was calculated using a random‑effects model.
Results: Twenty‑four studies with 110,404 food handlers were included. The overall pooled prevalence of intestinal protozoan infection was 14.1% (95% CI: 9.2% – 21.0%). Blastocystis hominis was the most common parasite (11.2%), followed by Entamoeba coli (8.2%), Giardia lamblia (5.4%), and Chilomastix mesnili (5.4%).
Conclusion: Approximately one in seven food handlers in Iran harbors intestinal protozoan parasites, with profound geographic disparities. Targeted interventions, including periodic stool screening and hygiene training, are urgently needed, particularly in high‑prevalence provinces.
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