Intestinal parasites among intellectually disabled individuals in Iran: a systematic review and meta-analysis

Poor self-care skills and personal hygiene resulted from limitations in learning and understanding, put intellectually disabled individuals at greater risk for intestinal parasitic infections (IPIs). Despite several regional reports in Iran, the overall burden on IPIs among intellectually disabled individuals is poorly understood. Hence, the present study aimed to estimate the pooled prevalence of IPIs among intellectually disabled individuals in Iran.

Using the PRISMA guidelines, we conducted a systematic review and meta-analysis of data retrieved from seven electronic databases (PubMed, Web of Science, Scopus, Embase, and ProQuest for English articles, as well as SID and Magiran for Persian) from their inception up to December 2020. Pooled prevalence was estimated using a random-effects model with a 95% confidence interval (CI) and depicted as a forest plot, while heterogeneity was evaluated using Cochran's Q-test.

Exactly 1263 of the 3004 intellectually disabled individuals examined by 14 studies across 10 provinces of Iran were positive for IPIs. Overall pooled prevalence estimate was 41% (95% CI 29-53%) with a range of 21% (95% CI 10-32%) to 68% (95% CI 55-80%) across sub-groups. Entamoeba coli (16.2%; 95% CI 10.3-22%), Blastocystis spp. (12.2%; 95% CI 7.2-17.2%), and Giardia duodenalis (11.9%; 95% CI 7.4-16.3%) were the most prevalent protozoan species. In terms of helminthic agents, the most prevalent species were Enterobius vermicularis (11.3%; 95% CI 6.3-16.3%) followed by Strongyloides stercoralis (10.9%; 95% CI 5.0-16.9%) and Hymenolepis nana (2.8%; 95% CI 0.4-5.2%) CONCLUSION: IPIs are highly prevalent among intellectually disabled individuals in Iran. Improving the health status and implementing infectious disease prevention strategies in rehabilitation centers, health promotion interventions to improve personal hygiene of intellectually disabled individuals, as well as utilize sensitive diagnostic methods besides routine stool examination techniques, and treatment of infected individuals will help in the control of these infections among intellectually disabled individuals.