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Bacillus Pre-Pasteurization Screening Protocol Reduces Donor Human Milk Loss
Sydney McCune1,2,3, Lisa Stellwagen1,3,4, Carrie L Byington1,3
1Human Milk Institute (HMI), University of California San Diego, La Jolla, California, USA.
Insights
Implementing pre-pasteurization screening for donor human milk significantly reduces discard rates caused by Bacillus contamination. This cost-effective strategy preserves valuable milk products for vulnerable infants, improving milk bank efficiency.
Area of Science:
- Microbiology
- Neonatal Nutrition
- Public Health
Background:
- Human milk is crucial for infant nutrition, especially for preterm infants.
- Pasteurized donor human milk (PDHM) is used for premature infants but faces contamination challenges.
- Spore-forming bacteria like Bacillus can survive pasteurization, leading to significant PDHM discard rates.
Purpose of the Study:
- To evaluate a novel pre-pasteurization screening protocol implemented in 2020 at the University of California Health Milk Bank.
- To assess the protocol's effectiveness in reducing discard rates and its cost efficiency over three years.
Main Methods:
- Analysis of three years of data from the University of California Health Milk Bank.
- Comparison of discard rates before and after implementing the pre-pasteurization screening protocol.
- Calculation of cost savings and return on investment associated with the screening protocol.
Main Results:
- Bacillus species accounted for 98% of post-pasteurization positive cultures.
- The pre-pasteurization screening protocol reduced the total discard rate due to Bacillus contamination from 3.1% to 1.2%.
- Without screening, an estimated 10.7% of PDHM could have been discarded; the protocol saved approximately 1,942,800 mL of milk valued at $323,800.
Conclusions:
- Pre-pasteurization screening is a highly effective method for reducing product loss in donor milk banks.
- The implemented protocol demonstrated significant cost savings, with a return on investment of $4.39 for every dollar spent.
- This approach enhances the safety and availability of pasteurized donor human milk for vulnerable infant populations.
Abstract:
Introduction: Human milk is the optimal source of nutrition and bioactives for infants, particularly preterm infants, who are at higher risk of morbidity and mortality. Many premature infants require pasteurized donor human milk (PDHM) to supplement their diet. Given the increased susceptibility of preterm infants to infections, PDHM is strictly regulated to ensure safety. Pasteurization of human milk eliminates most pathogens. However, spore-forming bacteria, notably Bacillus cereus and other Bacillus species, are capable of surviving pasteurization. These bacteria contribute significantly to PDHM discard rates, which average approximately 5-10% of the final donor milk products, making it a leading cause of contamination-related waste. Objective: The University of California Health Milk Bank adopted at their inception in 2020, a novel pre-pasteurization screening protocol with the aim to reduce discard rates. This study examines 3 years of data to assess the protocol's effectiveness and cost efficiency. Results: Ninety-eight percent of post-pasteurization positive cultures were Bacillus species. Following a pre-pasteurization screening protocol, the total discard rate due to Bacillus contamination was 3.1%-1.9% pre-pasteurization and 1.2% post-pasteurization. Without pre-pasteurization screening, 10.7% of PDHM could have potentially been discarded due to Bacillus contamination. The cost of pre-pasteurization screening of donor milk was $60,069 over 3 years, and the potential reduction in discard-related losses was 1,942,800 mL (64,760 ounces), with a value of approximately $323,800 for a return on investment of $4.39 per dollar spent. Conclusions: The findings highlight the role of pre-pasteurization screening cultures as a cost-effective method of reducing product loss.
