Comparative Microbial Contamination Profiles of Radiology Imaging Equipment in Public and Private Facilities in Abia State, Nigeria

Abstract

This cross-sectional study compared microbial contamination profiles on radiology imaging equipment in public and private facilities in Abia State, Nigeria, to establish baseline data for enhancing infection prevention and control measures in resource-limited settings. Between January and June 2025, 360 surface samples were collected from high-touch sites on X-ray machines, ultrasound units, and computed tomography scanners across three purposively selected public hospitals and three private diagnostic centres, using sterile swabs pre-moistened with saline, followed by culture on selective media, biochemical identification, antibiotic susceptibility testing, and log-transformed colony-forming unit quantification with statistical analysis using independent t-tests and chi-square tests. Microbial contamination was detected on 92% of surfaces, with significantly higher mean log-transformed colony-forming units per square centimetre in public facilities (1.69±0.28) compared to private ones (1.46±0.22; p<0.001), particularly on computed tomography scanners (public: 1.80±0.29; private: 1.54±0.23); predominant isolates included Staphylococcus aureus (35% public, 25% private), coagulase-negative staphylococci (25% public, 30% private), and Klebsiella species (20% public, 15% private), with multidrug-resistant strains affecting 45% of public isolates versus 25% in private settings, correlating positively with patient volumes (r=0.62, p<0.01) and inversely with cleaning frequency (r= -0.58, p<0.01). These findings highlight elevated healthcare-associated infection risks in public facilities due to resource constraints and operational burdens and the need for facility-specific decontamination protocols, routine microbial audits, and policy-driven resource reallocation to mitigate nosocomial transmission and foster equitable diagnostic safety.