Infections pose a risk for patients undergoing hematopoietic stem cell (HSC) transplants due to their immunosuppression, making them susceptible to opportunistic infections. Therefore, understanding the composition of the aerobiome in this area is vital. The aim of this study was to characterize the aerobiome in an HSC transplant area, evaluating the impact of infrastructure and health personnel operations on air contamination. The environmental parameters and aerobiome of the HSC transplant area at Hospital Juárez de México were quantified over one year. Finally, a double-entry Vester matrix was constructed to classify problems according to their degree of causality. The abundance and taxonomic diversity of the aerobiome were dependent on seasonality, environmental factors, and high-efficiency filtration. Gram-positive bacteria predominated, followed by fungi and Gram-negative bacteria. ANOVA revealed significant differences in the bacterial aerobiome but not in the fungal aerobiome among the transplant rooms. Clinically, fungi such as Aspergillus fumigatus, Alternaria spp., Cladosporium spp., and Penicillium spp. were identified. ESKAPE bacteria typing revealed clonal dispersion. Finally, the Vester matrix highlighted critical problems associated with contamination due to the absence of HEPA filtration and non-adherence in patient management practices. HEPA filtration and positive pressure are essential to improve the air quality and reduce the microbiological load. However, the control areas will depend on patient management and routine activities, such as entry protocols in controlled areas.

Healthcare-associated infections remain a central hospital challenge, particularly in critical areas where invasive procedures and microbial contamination overlap. The hospital environment, including air and high-touch surfaces, acts as a persistent microorganism source that favors stability and spread. UV-C disinfection systems have become complementary tools to conventional cleaning. This study evaluated the disinfectant efficacy of a 254 nm multiemitter UV-C system under in situ and in vitro conditions. A 254 nm UV-C multiemitter system was deployed to eight hospital areas selected for epidemiological relevance. Air and surface sampling were conducted before and after standardized UV-C cycles. The bacterial and fungal aerobiome was quantified (CFU/m³) and surfaces were characterized by MALDI-TOF mass spectrometry. In vitro assays tested efficacy against planktonic cultures and mature biofilms of clinical ESKAPE isolates and C. albicans. The UV-C intervention achieved mean aerobiome reductions above 91.5%, with complete elimination in multiple critical zones. Surface contamination was reduced by 96.1%, including total disinfection across several sampled points. In vitro testing showed ≥99.99% to 100% elimination of planktonic microorganisms. Mature biofilms exhibited full loss of viability after UV-C exposure, independent of biofilm architecture and structural complexity. Therefore, the 254 nm UV-C multiemitter system significantly reduced environmental microbial burden in critical hospital areas, supporting its integration within infection-prevention programs and reinforcing environmental biosafety through the control of the microbial sources involved in transmission dynamics.

Microbiological verification of reprocessed mechanical ventilators serves as a quality control measure aimed at interrupting potential transmission routes of pathogens before patient intubation. The aim of this study was to describe the microbiological findings and operational costs of the post-reprocessing surveillance program for mechanical ventilators at Hospital Juárez de México and to contextualize these costs using a hypothetical VAP-associated economic reference. This retrospective observational study included 1456 post-reprocessing microbiological evaluation events involving mechanical ventilators previously used by patients with laboratory-confirmed ventilator-associated pneumonia (VAP). All events meeting the surveillance eligibility criteria during the study period were included. Inspiratory and expiratory limbs were sampled for bacterial culture, with microbial identification by mass spectrometry. Any bacterial growth was considered residual contamination, and the ventilator underwent a new complete cycle of cleaning and high-level disinfection. An institutional analysis was applied to estimate operational costs and to contextualize the potential VAP-associated economic burden using the culture-positive ventilators as a hypothetical reference calculation, without assuming that each positive device represented a prevented VAP episode. Residual bacterial contamination was detected in 95 evaluation events (6.5%), with recovery of organisms including Acinetobacter baumannii and Pseudomonas aeruginosa. The operational cost of the microbiological surveillance program was 40,993 USD. Using institutional VAP cost estimates, a hypothetical calculation assigning the annual VAP cost to each of the 95 culture-positive evaluation events produced a reference value of 1,285,650 USD. Under this reference calculation, the difference between the VAP-associated reference value and program cost was 1,244,657 USD, corresponding to a cost ratio of 31.4:1. These estimates are hypothetical and depend on assumptions regarding infection probability and preventive effectiveness; they do not represent demonstrated economic savings. The break-even probability of device-attributable VAP per culture-positive evaluation event was 3.19%, assuming full institutional coverage of VAP-associated costs and complete prevention of these episodes through additional reprocessing. Within this defined surveillance population, microbiological surveillance of reprocessed mechanical ventilators is a useful quality-control strategy prior to patient intubation.