Molecular Detection and Genotyping of Human Adenovirus in Patients with Keratoconjunctivitis in Iraq

The objective of this study was to detect and genotype human adenovirus strains in patients suffering from ‎keratoconjunctivitis in Iraq. Additionally, it aimed to understand the distribution and prevalence of different ‎adenovirus types associated with the disease in this population.‎ Seventy conjunctival swabs and whole blood samples were collected from patients with suspected HAdV ‎infection. Viral DNA extracted and Conventional PCR was used to amplify the hexon gene, and the PCR ‎products were sequenced. Phylogenetic analysis was conducted using NCBI-BLAST and MEGA X to ‎compare local isolates with global strains.‎ of the 70 samples, 64 (91.4%) were positive for HAdV, with viral loads ranging from 1.32 × 10³ to 6.62 × 10⁸ ‎copies/mL. Genotyping revealed three predominant genotypes: HAdV-8 (50%), HAdV-54 (40%), and HAdV-‎‎19 (10%). Phylogenetic analysis showed high similarity with global strains, with sequence identities ranging ‎from 99.04% to 99.62%. Males and individuals aged 20–40 years were more frequently affected, with higher ‎infection rates observed in urban areas. No significant correlation was found between viral load and ‎demographic factors or clinical severity.‎ This study highlights the predominance of HAdV-8, HAdV-54, and HAdV-19 in Iraqi patients with ‎keratoconjunctivitis. The findings underscore the need for continuous surveillance and molecular ‎characterization of HAdV strains to inform public health interventions and prevent outbreaks‎.