Most common concurrent infections with COVID-19

Ahmed R. Zein, Emad A. Almuqati, Hebah H. Taher, Sarah S. Jahlan, Fatemah H. AlKhamis, Abdulwahab A. Almansour, Shoroq F. Alhazmi, Maha M. Alshehri, Mohamed I. Obaidat, Muath A. Alshehri, Zahra H. Alhoori


Concurrent infections are a common complication of viral respiratory infections. They pose diagnostic challenges due to an overlap of similar symptoms, resistance to treatment and extending length of hospital stay. In this review we will extensively discuss the most common concurrent infections in patients with coronavirus disease 2019 (COVID-19). A thorough literature search was conducted in online databases such as PubMed, Google Scholar and included systematic reviews, meta-analyses, prospective and retrospective cohort studies in this review. Bacterial co-infections are the most common concurrent infections in patients with COVID-19 succeeded by viral and fungal co-infections. The prevalence of co-infections in COVID-19 patients is higher in intensive care units (ICU). Gram negative bacteria such as Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, whereas gram positive bacteria such as Staphylococcus aureus are common pathogens for bacterial co-infections. The findings for the most common viral co-infection are inconsistent however, larger number of studies report respiratory viral co-infections such as influenza and respiratory syncytial virus. Fungal co-infections in COVID-19 patients are most commonly caused by the Candida spp. and occur predominantly in patients admitted in the ICU and are associated with high mortality and morbidity in COVID-19 patients. Continuous research on concurrent infections occurring in COVID-19 is essential. Larger prospective studies based on stratified groups of age, gender, and both ICU and non-ICU settings should be conducted. Studies on microbial susceptibility can lend more weight to empirical antibiotic and antifungal therapy. Early diagnosis of concurrent infections in COVID-19 is imperative to prevent poor patient outcomes.


COVID-19, Concurrent, Co-infection, Bacterial, Viral, Fungal

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