A comparative study on bacterial co-infections and prevalence of multidrug-resistant organisms among patients in COVID and non-COVID Intensive Care Units


Novel corona virus
hospital acquired infections
secondary bacterial infections
multidrug resistance
anti-microbial resistance


Introduction: Secondary bacterial infections have been reported in majority of patients hospitalized with coronavirus disease 2019 (COVID-19). A study of the antimicrobial susceptibility profiles of these bacterial strains revealed that they were multidrug resistant, demonstrating their resistance to at least three classes of antimicrobial agents including beta-lactams, fluoroquinolones and aminoglycosides.  Bacterial co-infection remains as an important cause for high mortality in patients hospitalized with COVID-19.

Methods: In our study, we conducted a retrospective comparative analysis of bacterial co-infections and the antimicrobial resistance profile of bacterial isolates obtained from inpatients admitted in COVID-19 and non COVID-19 intensive care units. The goal was to obtain the etiology and antimicrobial resistance of these infections for more accurate use of antimicrobials in clinical settings. This study involved a total of 648 samples collected from 356 COVID 19 positive patients and 292 COVID19 negative patients admitted in the intensive care unit over a period of six months from May to October 2020.

Results: Among the co-infections found, maximum antimicrobial resistance was found in Acinetobacter species followed by Klebsiella species in both the ICU's. Incidence of bacterial co-infection was found to be higher in COVID 19 intensive care patients and most of these isolates were multidrug resistant strains.

Conclusion: Therefore, it is important that co-infections should not be underestimated and instead be made part of an integrated plan to limit the global burden of morbidity and mortality during the SARS-CoV-2 pandemic and beyond.



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