Air dispersal of multidrug-resistant Acinetobacter baumannii: implications for nosocomial transmission during the COVID-19 pandemic

S. C. Wong, G. K.M. Lam, J. H.K. Chen, X. Li, F. T.F. Ip, L. L.H. Yuen, V. W.M. Chan, C. H.Y. AuYeung, S. Y.C. So, P. L. Ho, K. Y. Yuen, V. C.C. Cheng

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17 Citations (Scopus)

Abstract

Aim: To describe the nosocomial transmission of Air, multidrug-resistant, Acinetobacter baumannii, nosocomial, COVID-19 Acinetobacter baumannii (MRAB) in an open-cubicle neurology ward with low ceiling height, where MRAB isolates collected from air, commonly shared items, non-reachable high-level surfaces and patients were analysed epidemiologically and genetically by whole-genome sequencing. This is the first study to understand the genetic relatedness of air, environmental and clinical isolates of MRAB in the outbreak setting. Findings: Of 11 highly care-dependent patients with 363 MRAB colonization days during COVID-19 pandemic, 10 (90.9%) and nine (81.8%) had cutaneous and gastrointestinal colonization, respectively. Of 160 environmental and air samples, 31 (19.4%) were MRAB-positive. The proportion of MRAB-contaminated commonly shared items was significantly lower in cohort than in non-cohort patient care (0/10, 0% vs 12/18, 66.7%; P<0.001). Air dispersal of MRAB was consistently detected during but not before diaper change in the cohort cubicle by 25-min air sampling (4/4,100% vs 0/4, 0%; P=0.029). The settle plate method revealed MRAB in two samples during diaper change. The proportion of MRAB-contaminated exhaust air grills was significantly higher when the cohort cubicle was occupied by six MRAB patients than when fewer than six patients were cared for in the cubicle (5/9, 55.6% vs 0/18, 0%; P=0.002). The proportion of MRAB-contaminated non-reachable high-level surfaces was also significantly higher when there were three or more MRAB patients in the cohort cubicle (8/31, 25.8% vs 0/24, 0%; P=0.016). Whole-genome sequencing revealed clonality of air, environment, and patients' isolates, suggestive of air dispersal of MRAB. Conclusions: Our findings support the view that patient cohorting in enclosed cubicles with partitions and a closed door is preferred if single rooms are not available.

Original languageEnglish
Pages (from-to)78-86
Number of pages9
JournalJournal of Hospital Infection
Volume116
DOIs
Publication statusPublished - Oct 2021
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2021 The Healthcare Infection Society

ASJC Scopus Subject Areas

  • Microbiology (medical)
  • Infectious Diseases

Keywords

  • Acinetobacter baumannii
  • Air
  • COVID-19
  • multidrug-resistant
  • nosocomial

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