Blood culture contamination rates in India: a systematic review

Blood culture contamination remains a major quality indicator in clinical microbiology laboratories and directly influences patient management, antimicrobial stewardship, and healthcare costs. Contaminated blood cultures may lead to unnecessary antibiotic use, prolonged hospitalization, additional investigations, and increased healthcare expenditure. International guidelines recommend maintaining contamination rates below 2–3%, yet published data suggest significant variability across institutions and regions. India has diverse healthcare settings ranging from tertiary academic hospitals to peripheral centers, with heterogeneity in staffing, training, blood collection practices, and laboratory infrastructure. Despite the clinical importance of blood culture contamination, there is no consolidated synthesis of contamination rates reported from Indian healthcare institutions. Understanding the pooled contamination rate and identifying factors influencing variability is essential for benchmarking, quality improvement initiatives, and policy formulation. This systematic review aims to synthesize available evidence on blood culture contamination rates in India and evaluate determinants associated with higher contamination, thereby providing national-level evidence to inform laboratory practice and infection control strategies.