Secondary bacterial infections in pediatric respiratory syncytial virus lower respiratory tract illness: Insights from a tertiary care center in Eastern Odisha

Background: Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infections (ALRI) in children, often complicated by secondary bacterial infections that worsen outcomes. Aims and Objectives: (1) To assess the prevalence of secondary bacterial infections in RSV-associated ALRI among children ≤5 years. (2) To identify the bacterial pathogens and their antimicrobial susceptibility patterns. (3) To evaluate the clinical outcomes, including severity, intensive care unit (ICU) admissions, and mortality, in coinfected cases. Materials and Methods: A prospective study was conducted over 2 years in a tertiary care hospital in Eastern Odisha, enrolling 242 pediatric patients (≤5 years) with ALRI. Nasopharyngeal aspirates were tested for RSV by antigen detection and reverse transcription polymerase chain reaction, while bacterial pathogens were identified through culture and biochemical methods. Antimicrobial susceptibility was assessed using Clinical and Laboratory Standards Institute guidelines. Results: RSV was detected in 34 cases (14.05%). Among these, 11 children (32.35%) had secondary bacterial infections, predominantly infants (81.82%). Pneumonia was the most frequent manifestation (54.54%), with several requiring ICU care. The major bacterial isolates included Staphylococcus aureus (36.36%), Klebsiella pneumoniae (27.27%), Escherichia coli (18.18%), Streptococcus pneumoniae (9.09%), and Pseudomonas aeruginosa (9.09%). Most Gram‑positive isolates were sensitive to vancomycin and linezolid, while Gram‑negative bacilli showed high susceptibility to polymyxin B and tigecycline. Two deaths occurred, one associated with P. aeruginosa. Conclusion: RSV contributes substantially to pediatric ALRI in Eastern India, with secondary bacterial infections amplifying disease severity, particularly in infants. Early detection of coinfections and rational antibiotic use, supported by surveillance and stewardship programs, are critical to improving outcomes and reducing mortality.