Re-emergence and Epidemiologic Patterns of Giardiasis in Iranian Children: Drug-Resistance Concerns, Water-Scarcity Challenges, and Targeted Control Strategies

Introduction: Giardiasis, caused by Giardia lamblia, is a significant protozoal intestinal infection globally and a major contributor to pediatric morbidity in Iran. The infection's impact on children includes steatorrhea, malabsorption, growth retardation, and potential cognitive impairments. Recent environmental challenges, such as water scarcity and climate-related population shifts, coupled with concerns about treatment failures and emerging drug resistance, underscore the need to understand the current epidemiological landscape of giardiasis in Iran. This study aimed to determine the regional prevalence of giardiasis among Iranian children from ۲۰۱۰ to ۲۰۲۵, compare prevalence between healthy and immunocompromised groups, evaluate associated clinical outcomes, and propose strategic control measures. Methods: A systematic review following PRISMA guidelines was conducted, analyzing studies published between ۲۰۱۰ and ۲۰۲۵ from databases including PubMed, Scopus, Web of Science, SID, and MagIran. We included studies that reported on prevalence, molecular typing, clinical outcomes, or treatment responses in the Iranian pediatric population. Data extracted included geographic location, study year, participant characteristics (healthy, immunocompromised), diagnostic methods (microscopy, EIA, PCR), prevalence rates, Giardia genotypes, and clinical manifestations. Results: Sixty-two studies met the inclusion criteria. The analysis revealed pediatric giardiasis prevalence of ۱۰.۶% (۹۵% CI: ۹.۶-۱۱.۵%). Higher prevalence rates, nearing ۲۸-۳۰%, were found in provinces like Sistan & Baluchestan and Khuzestan, as well as in rural areas of Fars and Kerman. Conversely, some urban outpatient cohorts, such as those in Shiraz, showed a much lower prevalence (۱%). Immunocompromised children, including those with HIV, transplant recipients, or primary immunodeficiencies, exhibited a considerably higher prevalence, reaching up to ۳۹% in some series. Molecular analysis identified assemblages A (subtype AII) and B (BIII/BIV) as the dominant strains. Clinically, ۲۰-۶۰% of symptomatic cases presented with acute or chronic diarrhea, and there was an increased risk of stunting and wasting in children with early-life infections. While treatment responses to metronidazole and tinidazole were variable, a lack of comprehensive national surveillance for antimicrobial resistance was identified. Environmental factors like water scarcity and climate-driven internal migrations were consistently associated with increased prevalence in multiple regional studies. Conclusion: Giardiasis persists as a significant, regionally concentrated etiology of pediatric enteric disease in Iran. Environmental stressors and particularly vulnerable subpopulations (immunocompromised children) exacerbate the burden of disease. It is recommended to enhance molecular diagnostics, establish sentinel surveillance (incorporating treatment outcome monitoring), invest in water, sanitation, and hygiene (WASH) systems resilient to drought, and implement targeted screening and treatment strategies in high-risk populations.

کلیدواژه ها:

Giardiasis ، Children ، Iran