Original Article

Frequency and antimicrobial resistance pattern of bacterial isolates from patients with COVID-19 in two hospitals of Zanjan


Background and Objectives: The outbreak of COVID-19 has been challenging the global health systems. As one of the major associated concerns, microbial co-infections and antimicrobial resistance play critical roles in the prognosis of the disease. This study aims to evaluate co-infections in COVID-19 patients regarding drug resistance.
Materials and Methods: A total number of 5530 Real Time PCR-confirmed COVID-19 cases, who were admitted to two major educational Hospitals in Zanjan, Iran, from February 2019 to February 2020 were included. Respiratory, blood and urine specimens were collected and cultured on selective media. Subsequently, isolates identification, disc diffusion susceptibility tests, and data analysis were carried out.
Results: Bacterial and fungal co-infections were confirmed in 423 patients (8.1%). Co-infections were more prevalent among females (53.2%) than males (46.8%). Coinfected patients had a significantly higher mortality rate compared to those without co-infections (54.8% vs. 12.2%, P<0.001). Acinetobacter baumannii was the most prevalent bacteria isolated from respiratory tract (15.4%) and blood (2.1%). Escherichia coli (12.5%) was the most frequent bacteria in urine. Fungal co-infection was confirmed in 174 (3.36%) patients. Gram-negative bacteria were highly sensitive to colistin (97.85%) and widely resistant to cefixime (91.79%) and trimethoprim-sulfamethoxazole (89.64%). Gram-positive bacteria were considerably sensitive to vancomycin (68%) and nitrofurantoin (66%). Tetracycline and ampicillin were the least effective antibiotics for Gram-positive bacteria with respective resistance rates of 90.91% and 83.33%.
Conclusion: Given the high incidence of bacterial co-infections in COVID-19 patients, it is important to develop rapid and efficient diagnostic, therapeutic and disinfection guidelines to control these infections in the hospitals.

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IssueVol 13 No 6 (2021) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/ijm.v13i6.8078
Bacterial co-infections; COVID-19; Susceptibility testing; SARS-CoV-2

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How to Cite
Moradi N, Kazemi N, Ghaemi M, Mirzaei B. Frequency and antimicrobial resistance pattern of bacterial isolates from patients with COVID-19 in two hospitals of Zanjan. Iran J Microbiol. 2021;13(6):769-778.