Microbial ecology of protective isolation room: Air and Surfaces


Yousra Sbibih
Abderrazak Saddari
Ilham Alla
Oumayma Abdesselami
Chaymae Ben moussa
Said Ezrari
Elmostapha Benaissa
Yassine Ben Lahlou
Mostafa Elouennass
Adil Maleb


Introduction: Healthcare-associated infections pose a significant public health burden, leading to morbidity, mortality, prolonged hospital stays, and substantial social and economic costs. Immunocompromised patients are at a heightened risk of nosocomial infections.

Aim: This prospective study conducted at Mohammed VI University Hospital of Oujda aimed to assess the microbial ecology of surfaces and air in an immunosuppressed patient room compared to a double hospitalization room.

Methods:  Microbiological air purity tests were conducted employing both the sedimentation method and the collision method with the assistance of Microflow Alpha. The sedimentation method used Mueller Hinton with 5% human blood, facilitating the free fall of contaminated dust particles. The collection program employed was set for 10 minutes per 1 m3. For surface sampling, swabs were taken from a 25 cm2 surface. The swabs were immediately forwarded to the Microbiology Laboratory. We carried out both macroscopic and microscopic identification of colonies, followed by definitive biochemical identification using the BD phoenixTM system. Antibiotic susceptibility was assessed through agar diffusion on Muller Hinton medium coupled with the determination of the minimum inhibitory concentration.

Results: The results revealed a decreased bacterial count within the protective isolation room, in contrast to the standard hospital room. We noted the predominance of coagulase-negative Staphylococcus spp and Bacillus spp. Staphylococcus aureus and Aspergillus spp, common pathogens in healthcare-associated infections, were notably absent in the protective isolation room. The findings underline the pivotal role of hospital environments in the transmission of healthcare-associate  ..(abstract truncated at 250 words)


microbial ecology, protective isolation room, immunocompromised patient, healthcare-associated infections.



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