Postpasteurization Testing of Human Milk Sterility at Human Milk Banks in Resource-Limited Settings: An Alternative to Standard Microbiological Quality Testing.

Introduction: Pasteurized donor human milk provides nutrition and bioactive factors for infant growth and health when a mother's own milk is not available. Bacteriological testing is recommended for each pasteurized batch of donor milk before distribution to ensure that the milk is safe for use. Charm Peel Plates (CPPs) are a simplified, easy-to-use culture method for detecting microorganisms in milk and milk products. This study investigates the feasibility of using CPPs as an alternative test for current standard postpasteurization screening by human milk banks (HMBs), particularly those in resource-limited settings. Aim: The aim of this study was to evaluate the feasibility of using the CPP versus the 5% horse blood agar (HBA) plate (standard South African National Health Laboratory Service method) for detecting bacterial growth in pasteurized human milk samples. Methods: For each of the 50 pasteurized donor milk samples, 100-μL aliquots were cultured on routine HBA and 1 mL on CPPs for the total bacterial colony count. Any positive growth was identified using VITEK ^® 2 (bioMérieux). To demonstrate the ability of CPPs to support bacterial growth, four spiked samples were tested. Results: Concurrent negative test results were reported for 49/50 (98%) samples with only one positive test with HBA. Conclusions and Recommendations: The CPP is equivalent to HBA for detection of bacterial growth. Additional advantages of CPPs are ease of use and cost-effectiveness. The CPP is therefore recommended as a point-of-care, bacteriological screening method for donor human milk by HMBs, particularly those in resource-limited settings.