Air Quality and Hospital-Acquired Infections: A Case Study of Ventilation and Bioaerosols in an Educational Hospital

Background: Hospital-acquired infections (HAIs) pose a significant threat to patient health and healthcare systems. Adequate ventilation is one of the most effective methods for controlling and preventing the spread of infectious pathogens in healthcare settings. Objectives: This study investigates the correlation between ventilation systems, bioaerosol density, and the prevalence of HAIs. Methods: This descriptive-analytical study was conducted at an educational hospital in Mashhad. Data were collected from 473 patients. To measure air velocity, a TES 1340 anemometer was used to assess airflow speed. Bioaerosol sampling followed the NIOSH 0800 standard method. Data analysis was conducted using SPSS version 26. Results: Data analysis revealed a strong inverse correlation between bioaerosol concentration and both relative humidity (P = 0.001) and air changes per hour (ACH) (P = 0.001), whereas a direct relation was observed between bioaerosol concentration and temperature (P = 0.001). Additionally, the type of infection significantly correlated with the department type (P = 0.005), but not with patient gender (P = 0.091). Among infection types, Acinetobacter infections were most prevalent (41, 25%), particularly in ICU3. Staphylococcus aureus was the most common infection in the emergency surgery department. Candida infections were significantly influenced by ACH, while S. aureus prevalence increased with higher humidity and affected younger patients. Bioaerosol concentrations were highest for S. aureus and lowest for Candida, with no significant impact of temperature on infection distribution. Conclusions: The findings emphasize the critical role of ventilation systems and environmental control measures in preventing airborne transmission of pathogens and reducing HAIs. Further research is needed to optimize ventilation strategies and minimize the risk of infection.