en Other Other Original article Original article <b><span style="font-size:10.0pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">Introduction: </span></span></span></b><span style="font-size:10.0pt"><span style="background:white"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">Secondary bacterial and fungal infections are a significant concern in COVID-19 patients, particularly those critically ill and requiring intensive care. This retrospective study investigated the prevalence and spectrum of secondary infections among COVID-19 patients admitted to the intensive care unit (ICU) at a tertiary care hospital in Navi Mumbai. Additionally, we explored the association between secondary infections and patient comorbidities</span></span></span></span><span style="font-size:10.0pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">. <b>Methods</b>: </span></span></span><span style="font-size:10.0pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">We performed a single-center, retrospective cohort study of 3234 COVID-19 patients admitted to a tertiary care hospital in Navi Mumbai, India, between August 2020 and August 2021. Microbiological data from various clinical specimens, including blood, sputum, bronchoalveolar lavage (BAL) fluid, urine, and tissue cultures, were retrospectively analyzed. Patient demographics and comorbidities were extracted from medical records. We employed descriptive statistics and Pearson&#39;s Chi-square test for data analysis to identify associations between secondary infections and patient characteristics. <b>Results: </b></span></span></span><span style="font-size:10.0pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">Among the 3234 COVID-19 patients, 195 (6.02%) presented with clinical features suggestive of secondary infections. Microbiological analysis confirmed secondary infections in 98 patients (3.03%), with a culture positivity rate of 50.3%. Among bacterial isolates, <i>Klebsiella pneumoniae</i> was the most prevalent (43.28%), followed by <i>Acinetobacter baumannii</i> (25.37%). <i>Aspergillus</i> spp. emerged as the dominant fungal pathogen. Notably, <i>Escherichia coli</i> isolation was significantly associated with various specimen types (<i>P</i> < 0.001). However, no significant correlation was found between secondary infection rates and patient comorbidities</span></span></span><span style="font-size:10.0pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">. <b>Conclusion: </b></span></span></span><span lang="EN-GB" style="font-size:10.0pt"><span style="line-height:107%"><span new="" roman="" style="font-family:" times="">Gram-negative bacteria, specifically <i>K. pneumoniae</i> and <i>A. baumannii</i>, were the primary pathogens responsible for secondary infections in our cohort of critically ill COVID-19 patients admitted to the ICU. These findings underscore the importance of ongoing surveillance and monitoring of secondary infection trends, including fungal pathogens, to inform and optimize management strategies in this high-risk population. </span></span></span> Tertiary care hospital, Secondary infection, Retrospective, Intensive care unit, Klebsiella pneumoniae, Acinetobacter baumannii, Aspergillus spp., Antimicrobial resistance 76 83 http://jommid.pasteur.ac.ir/browse.php?a_code=A-10-523-1&slc_lang=en&sid=1 Anila Prabil anilaprabil1@gmail.com 0009-0007-6169-4244 Yes Department of Microbiology, Terna Medical College, Nerul, Navi Mumbai, Maharashtra, India Murtaza Gandhi 0000-0002-2802-6785 No Department of Microbiology, Terna Medical College, Nerul, Navi Mumbai, Maharashtra, India Veena Rani Vemuri 0000-0001-9950-146x No Department of Pharmacology, Terna Medical College, Nerul, Navi Mumbai, Maharashtra, India