Tehran University of Medical Sciences Journal of Arthropod-Borne Diseases 2322-1984 20 2 2026 08 15 1962 1962 Gafar Jalali Department of Medical Entomology and Vector Control, School of Public Health, Urmia University of Medical Sciences, Urmia, Iran Hamid Kassiri Department of Medical Entomology and Vector Control, School of Public Health, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Saber Gholizadeh Department of Medical Entomology and Vector Control, School of Public Health, Urmia University of Medical Sciences, Urmia, Iran, Pathogens and Vectors Research Center, Cellular and Molecular Medicine Research Institute, Urmia University of Medical Sciences, Urmia, Iran Mehdi Badakhshan Department of Medical Entomology and Vector Control, School of Public Health, Urmia University of Medical Sciences, Urmia, Iran, Pathogens and Vectors Research Center, Cellular and Molecular Medicine Research Institute, Urmia University of Medical Sciences, Urmia, Iran 2026 06 07 2026 08 06 Background: Demodex folliculorum (Acariformes: Demodicidae) is a common human ectoparasite associated with various inflammatory skin and ocular disorders. This study investigated the prevalence, associated factors and molecu­lar characteristics of D. folliculorum among individuals attending primary healthcare centers in Khuzestan Province, southwestern Iran. Methods: In this cross-sectional study, 228 participants underwent cutaneous and ocular sampling for Demodex detection using a light microscope. Selected positive samples were identified molecularly by 18S rDNA sequencing. Demographic, behavioral and clinical data were collected using standardized questionnaires. Variables associated with infestation were evaluated by univariate analyses and multivariable binary logistic regression. Results: Cutaneous Demodex infestation was detected in 20 participants (8.77%), while ocular infestation was identified in three participants. Molecular analysis confirmed all sequenced isolates as D. folliculorum, showing >99% similarity with reference sequences and only minor genetic polymorphisms. Multivariable analysis identified high psychological stress (adjusted odds ratio [AOR]=5.51, 95% confidence interval [CI]: 1.84–16.47; p=0.002) and active facial skin lesions (AOR=4.01, 95% CI: 1.22–13.20; p=0.022) as independent predictors of infestation. Ocular findings were reported descriptively because of the limited number of positive cases. Conclusions: Demodex folliculorum infestation was relatively uncommon in this population but was independently associated with psychological stress and active facial skin lesions. Molecular findings demonstrated close genetic similarity between local and globally reported isolates. These results improve understanding of the epidemiology of demodicosis and support molecular identification in epidemiological investigations. https://jad.tums.ac.ir/index.php/jad/article/view/1962 https://jad.tums.ac.ir/index.php/jad/article/download/1962/737