Zainab Hazim Ismael ALYAIS
Department of Veterinary Public Health / College of Veterinary Medicine / University of Baghdad
Ali Hassan Ahmed Al-Shammary
Department of Veterinary Public Health / College of Veterinary Medicine / University of Baghdad
ABSTRACT
This study addresses the challenge of combating Acinetobacter baumannii ("Iraqibacter") contamination in the local dairy chain and its role in urinary tract infections (UTI) through the innovative use of redirected lytic bacteriophage cocktails. A. baumannii, known for its recalcitrant biofilm formation and multidrug-resistant (MDR) phenotype, poses significant threats to public health. Lytic bacteriophages with broad-spectrum antimicrobial activity were isolated from Abu-Ghraib fresh ropy yogurt in Baghdad. These phages were assessed for their efficacy against A. baumannii strains recovered from dairy products and UTI cases, which demonstrated resistance to multiple generations of antibiotics and ultraviolet irradiation. The study utilized advanced methodologies, including isolation of bacteriophages from yogurt, experimental contamination of ultra-high-temperature (UHT) milk units with A. baumannii, and the application of refrigeration preservation cascades. The efficacy of bacteriophage cocktails was validated using plaque assays and scanning electron microscopy (SEM) to document the interaction between bacteriophages and A. baumannii. The SEM micrographs revealed significant disruption of biofilm structures and bacterial cell integrity upon exposure to phages. The findings demonstrate that redirected lytic bacteriophages offer a highly specific and eco-friendly alternative to traditional antimicrobial approaches, effectively eliminating A. baumannii contamination in the dairy chain without evidence of forbidden transduction or prophage activation. This study highlights the potential of bacteriophage-based biocontrol as a sustainable intervention against MDR pathogens in food safety and clinical settings.
Keywords: Acinetobacter baumannii, Multi Stress Hardening, Yogurt, Lytic Bacteriophages.
