Bacterial safety of flash-heated and unheated expressed breastmilk during storage

Midwifery and Nursing Strategies to protect against COVID-19 During the Third Trimester of Pregnancy

Objective

The rapid pace of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic (COVID-19) presents significant challenges to midwives and nurses. This study aimed to explore midwifery and nursing interventions to limit the transmission of COVID-19 among women in their third trimester of pregnancy, to reduce the incidence of nosocomial infection and promote safety of care for women and their infants.

Method

We completed a retrospective review of medical records from 35 women in their third trimester of pregnancy with SARS-CoV-2, admitted to one hospital in Wuhan, China in January and February 2020. We investigated the clinical characteristics of the COVID-19 infection in pregnancy, and the individualized midwifery and nursing care offered, including environmental protection, prevention of nosocomial infection, maternal observations, monitoring of signs and symptoms of COVID-19, and psychological care.

Result

Thirty-one women had a caesarean section, and four had vaginal births. Retrospective analysis of midwifery and nursing strategies implemented to care for these women showed no maternal complications or nosocomial infections.

Conclusions and implications for practice

The care strategies we implemented could prevent complications and nosocomial infection in the third trimester of pregnancy, thus ensuring the safety of women and their infants. Further research needs to determine treatment priorities for women infected with COVID-19 during pregnancy and the postnatal period.

Innovative Techniques of Processing Human Milk to Preserve Key Components

Human milk not only contains all nutritional elements that an infant requires, but is also the source of components whose regulatory role was confirmed by demonstrating health-related deficiencies in formula-fed children. A human milk diet is especially important for premature babies in the neonatal intensive care unit (NICU). In cases where breastfeeding is not possible and the mother's own milk is insufficient in volume, the most preferred food is pasteurized donor milk. The number of human milk banks has increased recently but their technical infrastructure is continuously developing. Heat treatment at a low temperature and long time, also known as holder pasteurization (62.5 °C, 30 min), is the most widespread method of human milk processing, whose effects on the quality of donor milk is well documented. Holder pasteurization destroys vegetative forms of bacteria and most viruses including human immunodeficiency virus (HIV) herpes and cytomegalovirus (CMV). The macronutrients remain relatively intact but various beneficial components are destroyed completely or compromised. Enzymes and immune cells are the most heat sensitive elements. The bactericidal capacity of heat-pasteurized milk is lower than that of untreated milk. The aim of the study was for a comprehensive comparison of currently tested methods of improving the preservation stage. Innovative techniques of milk processing should minimize the risk of milk-borne infections and preserve the bioactivity of this complex biological fluid better than the holder method. In the present paper, the most promising thermal pasteurization condition (72 °C-75 °C,) and a few non-thermal processes were discussed (high pressure processing, microwave irradiation). This narrative review presents an overview of methods of human milk preservation that have been explored to improve the safety and quality of donor milk.

Effect of the PiAstra Benchtop Flash-Heating Pasteurizer on Immune Factors of Donor Human Milk

INTRODUCTION

PiAstra is a simulated flash-heat (FH) pasteurization temperature monitoring system designed using Raspberry Pi technology for the pasteurization of human milk. This study analyzed the effect of the PiAstra FH method on human milk immune components (immunoglobulin A [IgA] and lactoferrin activity).

METHODS

Donor milk samples (N = 45) were obtained from a human milk bank, and pasteurized. Concentrations of IgA and lactoferrin activity were compared to their unpasteurized controls using the Student's t test.

RESULTS

The PiAstra FH method retained 34.2% of IgA (p < 0.0001) and 40.4% of lactoferrin activity (p < 0.0001) when compared to unpasteurized controls. The retention of IgA by the PiAstra is similar to previous FH studies, while retention of lactoferrin activity was higher than previous FH studies.

DISCUSSION

The high-technology, low-cost PiAstra system, which is able to retain vital immune components of human milk, provides safe donor milk for low-resourced settings. This enables the use of pasteurized donor milk when human milk is not available, potentially saving vulnerable infant lives.

The effect of simulated flash heating pasteurisation and Holder pasteurisation on human milk oligosaccharides

BACKGROUND

Human milk oligosaccharides (HMOs) have important protective functions in human milk. A low-cost remote pasteurisation temperature-monitoring system has been designed using FoneAstra, a cell phone-based networked sensing system to monitor simulated flash heat pasteurisation.

AIM

To compare the pasteurisation effect on HMOs of the FoneAstra FH method with the current Sterifeed Holder method used by human milk banks.

METHODS

Donor human milk samples (n = 48) were obtained from a human milk bank and pasteurised using the two pasteurisation methods. HMOs were purified from samples and labelled before separation using high-performance liquid chromatography. Concentrations of total HMOs, sialylated and fucosylated HMOs and individual HMOs using the two pasteurisation methods were compared using repeated-measures ANOVA.

RESULTS

The study demonstrated no difference in total concentration of HMOs between the two pasteurisation methods and a small but significant increase in the total concentration of HMOs regardless of pasteurisation methods compared with controls (unpasteurised samples) (p<0.0001).

CONCLUSION

The FoneAstra FH pasteurisation system does not negatively affect oligosaccharides in human milk and therefore is a possible alternative for providing safely sterilised human milk for low- and middle-income countries.

Human Milk-Treatment and Quality of Banked Human Milk

The aim of human milk banks is to deliver safe and high quality donor human milk. Treatment of human milk has to destroy most microorganisms while preserving immunological and nutrient components, which is obtained when using low time low temperature pasteurization. However it destroys bile-simulated lipase, reduces lactoferrin, lysozyme, immunoglobulins, and bactericidal capacity of human milk. New methods are under investigation such as high temperature short time pasteurization, high pressure processing, or ultraviolet irradiation. They have been tested in experimental conditions and there are promising results, but they have to be tested in real conditions in human milk bank.

The Effect of Simulated Flash-Heat Pasteurization on Immune Components of Human Milk

A pasteurization temperature monitoring system has been designed using FoneAstra, a cellphone-based networked sensing system, to monitor simulated flash-heat (FH) pasteurization. This study compared the effect of the FoneAstra FH (F-FH) method with the Sterifeed Holder method currently used by human milk banks on human milk immune components (immunoglobulin A (IgA), lactoferrin activity, lysozyme activity, interleukin (IL)-8 and IL-10). Donor milk samples (N = 50) were obtained from a human milk bank, and pasteurized. Concentrations of IgA, IL-8, IL-10, lysozyme activity and lactoferrin activity were compared to their controls using the Student’s t-test. Both methods demonstrated no destruction of interleukins. While the Holder method retained all lysozyme activity, the F-FH method only retained 78.4% activity (p < 0.0001), and both methods showed a decrease in lactoferrin activity (71.1% Holder vs. 38.6% F-FH; p < 0.0001) and a decrease in the retention of total IgA (78.9% Holder vs. 25.2% F-FH; p < 0.0001). Despite increased destruction of immune components compared to Holder pasteurization, the benefits of F-FH in terms of its low cost, feasibility, safety and retention of immune components make it a valuable resource in low-income countries for pasteurizing human milk, potentially saving infants’ lives.

Demonstrating the efficacy of the FoneAstra pasteurization monitor for human milk pasteurization in resource-limited settings

Human milk provides crucial nutrition and immunologic protection for infants. When a mother's own milk is unavailable, donated human milk, pasteurized to destroy bacteria and viruses, is a lifesaving replacement. Flash-heat pasteurization is a simple, low-cost, and commonly used method to make milk safe, but currently there is no system to monitor milk temperature, which challenges quality control. FoneAstra, a smartphone-based mobile pasteurization monitor, removes this barrier by guiding users through pasteurization and documenting consistent and safe practice. This study evaluated FoneAstra's efficacy as a quality control system, particularly in resource-limited settings, by comparing bacterial growth in donor milk flash-heated with and without the device at a neonatal intensive care unit in Durban, South Africa.

MATERIALS AND METHODS

For 100 samples of donor milk, one aliquot each of prepasteurized milk, milk flash-heated without FoneAstra, and milk pasteurized with FoneAstra was cultured on routine agar for bacterial growth. Isolated bacteria were identified and enumerated.

RESULTS

In total, 300 samples (three from each donor sample) were analyzed. Bacterial growth was found in 86 of the 100 samples before any pasteurization and one of the 100 postpasteurized samples without FoneAstra. None of the samples pasteurized using FoneAstra showed bacterial growth.

CONCLUSIONS

Both pasteurization methods were safe and effective. FoneAstra, however, provides the additional benefits of user-guided temperature monitoring and data tracking. By improving quality assurance and standardizing the pasteurization process, FoneAstra can support wide-scale implementation of human milk banks in resource-limited settings, increasing access and saving lives.

Barriers and promoters of home-based pasteurization of breastmilk among HIV-infected mothers in greater Dar es Salaam, Tanzania

BACKGROUND

For the past decade, heat-treating breastmilk has been an infant feeding option recommended by the World Health Organization as a strategy to reduce vertical transmission. However, little is known about field experiences with it. Our primary objective was to explore the barriers and promoters of the implementation of breastmilk pasteurization, "flash-heating" (FH), in the real-world setting of Dar es Salaam, Tanzania.

SUBJECTS AND METHODS

Nineteen in-depth interviews were conducted with participants in a home-based infant feeding counseling intervention in which FH was promoted after 6 months of exclusive breastfeeding. Additionally, three focus group discussions were conducted with peer counselors. Interviews were transcribed, translated, and coded independently using NVivo 8 software (QSR International). Data were analyzed using the socioecological framework.

RESULTS

Information and support provided by peer counselors were the most important promoters of initiation and continuation of FH; this impacted individual-, interpersonal-, and institutional-level promoters of success. Other promoters included perceived successful breastmilk expression, infant health after initiation of FH, and the inability to pay for replacement milks. Stigma was the most important barrier and cut across all levels of the framework. Other barriers included doubt about the safety or importance of pasteurized breastmilk, difficulties with expressing milk (often attributed to poor diet), and competing responsibilities. The most common suggestion for improving the uptake and duration of FH was community education.

CONCLUSIONS

Given the acknowledged role of breastmilk pasteurization in the prevention of vertical transmission, further implementation research is needed. A multilevel intervention addressing barriers to FH would likely improve uptake.

Addressing social barriers and closing the gender knowledge gap: exposure to road shows is associated with more knowledge and more positive beliefs, attitudes and social norms regarding exclusive breastfeeding in rural Zimbabwe

Exclusive breastfeeding (EBF) is rarely practiced despite its significant child survival benefits. A key constraint to increasing EBF rates in Zimbabwe and most of the developing world is that key decision makers (fathers/partners and other family members) are often poorly informed about EBF and do not attend antenatal clinics where health information is routinely provided. Informed by formative research, a district-wide campaign was conducted in rural Zimbabwe to encourage EBF and expressing and heat treating (EHT) breast milk as a means to maintain EBF. The campaign combined traditional strategies of education, counselling and outreach through health service delivery with a novel road show 'edutainment' intervention to reach men and other community members. A post campaign evaluation measured the association of road show exposure with 20 knowledge items and summative scores of social norms, beliefs and attitudes obtained through exploratory factor analysis. In adjusted models, road show exposure was associated with correct EBF knowledge (β=1.0, 0.001), EHT knowledge (β=1.3, P<0.001) and greater perceived benefits of condom use during pregnancy and breastfeeding (β=0.5, P<0.001), and more positive EBF social norms (β=0.6, P<0.001), EBF beliefs and attitudes (β=1.0, P<0.001) and attitudes towards condom use during breastfeeding (β=0.6, P<0.001). Road show exposure was more strongly associated with EBF knowledge among men (P-value for gender×exposure group interaction=0.03), suggesting that it also closed the knowledge gap between men and women. Longitudinal studies will determine whether road shows were associated with changes in EBF practices.

Impact of pasteurization on the antibacterial properties of human milk

Growing evidence favours the use of human milk for the feeding of preterm newborns based on its many beneficial effects. Despite the many benefits, human milk has been associated as a possible vehicle of transmission for a number of infections. Although pasteurization of human milk can diminish the risk of neonatal infection, it also significantly reduces the concentrations of immunological components in human milk due to thermal damage. In order to evaluate the impact of pasteurization on the antibacterial properties of human milk, we aimed to compare the capacity of raw and pasteurized human milk to inhibit bacterial proliferation. Therefore, a single milk sample was collected from ten healthy lactating mothers. Each sample was divided into two aliquots; one aliquot was pasteurized, while the other was kept raw. Both aliquots were inoculated either with Escherichia coli or Staphylococcus aureus and incubated at 37 °C during 8 h. Viable colony counts from the inoculated samples were performed at regular time points to compare the bacterial growth in both forms of breast milk. Relative to the tryptic soy broth control sample, both raw and pasteurized milk samples exhibited an inhibitory effect on the growth of E. coli and S. aureus. Compared with the raw portion, growth inhibition was significantly lower in the pasteurized milk at every time point beyond T0 (after 2, 4 and 8 h of incubation) (p = 0.0003 for E. coli and p < 0.0001 for S. aureus).

CONCLUSION

Our study shows that pasteurization adversely affects the antibacterial properties of human milk.

Development of an AFASS assessment and screening tool towards the prevention of mother-to-child HIV transmission (PMTCT) in sub-Saharan Africa--a Delphi survey

Background

The rate of mother-to-child transmission of HIV, occurring during pregnancy, delivery/labour and breastfeeding, still remains high in Sub-Saharan Africa (SSA). The World Health Organization recommends HIV infected mothers exclusively breastfeed their infants, unless replacement feeding is Acceptable, Feasible, Affordable, Sustainable and Safe (AFASS). Health care workers are responsible for providing counselling to mothers on the risks and benefits of infant feeding options allowing mothers to make an ‘informed choice’, but this role is challenging and mostly subjective. The aim of this study was to develop and content validate an AFASS assessment tool that could be used for infant feeding counselling in SSA.

Methods

An AFASS assessment tool was developed based on the evidence and tools available regarding why replacement feeding is not AFASS in SSA (15 questions). Fifty seven experts involved in PMTCT programmes in five SSA countries were approached to participate as members of the Delphi expert panel (purposive sampling and snowballing). A web-based survey, utilising a 4-point Likert scale, was employed to gain consensus (>75% agreement) from the expert panel following the Delphi technique.

Results

A final panel of 15 experts was obtained. Thirteen of the 15 questions in the tool achieved consensus agreement. Experts suggested some additional questions, and that double-barrelled questions were split. Consensus was achieved regarding the applicability and appropriateness of the tool within a SSA context. Experts all agreed that the tool will be useful for the purpose for which it was designed. Suggestions made by the expert panel were incorporated into the revised tool.

Conclusions

The findings of this study confirm that this AFASS counselling tool may be appropriate and useful for SSA. Ideally the revised tool should be tested by providers of infant feeding advice with the aim of adoption into routine PMTCT programmes in SSA. Within the context of the 2010 WHO guidelines which advocate a public health rather than an individualised approach, it may inform the WHO process of improving counselling tools for health care workers involved in PMTCT programmes.

Feasibility of using flash-heated breastmilk as an infant feeding option for HIV-exposed, uninfected infants after 6 months of age in urban Tanzania

OBJECTIVE

Heat-treating expressed breastmilk is recommended as an interim feeding strategy for HIV-exposed infants in resource-poor countries, but data on its feasibility are minimal. Flash-heating (FH) is a simple in-home technique for heating breastmilk that inactivates HIV although preserving its nutritional and anti-infective properties. Our primary objective was to determine, among HIV-infected mothers, the feasibility and protocol adherence of FH expressed breastmilk after 6 months of exclusive breastfeeding.

DESIGN

Prospective longitudinal.

PARTICIPANTS

One hundred one HIV-infected breastfeeding mothers.

SETTING

Dar es Salaam, Tanzania.

INTERVENTION

Peer counselors provided in-home counseling and support on infant feeding from 2 to 9 months postpartum. Mothers were encouraged to exclusively breastfeed for 6 months followed by FH expressed breastmilk if her infant was HIV negative. Clinic-based staff measured infant growth and morbidity monthly, and mothers kept daily logs of infant morbidity. FH behavior was tracked until 9 months postpartum using daily logs, in-home observations, and clinic-based and home-based surveys. Bacterial cultures of unheated and heated milk samples were performed.

RESULTS

Thirty-seven of 72 eligible mothers (51.4%) chose to flash-heat. Median (range) frequency of milk expression was 3 (1-6) times daily and duration of method use on-study was 9.7 (0.1-15.6) weeks. Mean (SD) daily milk volume was 322 (201) mL (range 25-1120). No heated and 32 (30.5%) unheated samples contained bacterial pathogens.

CONCLUSIONS

FH is a simple technology that many HIV-positive women can successfully use after exclusive breastfeeding to continue to provide the benefits of breastmilk while avoiding maternal-to-child transmission associated with nonexclusive breastfeeding. Based on these feasibility data, a clinical trial of the effects of FH breastmilk on infant health outcomes is warranted.

Effect of flash-heat treatment on antimicrobial activity of breastmilk

BACKGROUND AND OBJECTIVES

The World Health Organization recommends human immunodeficiency virus (HIV)-positive mothers in resource-poor regions heat-treat expressed breastmilk during periods of increased maternal-to-child transmission risk. Flash-heat, a "low tech" pasteurization method, inactivates HIV, but effects on milk protein bioactivity are unknown. The objectives were to measure flash-heat's effect on antimicrobial properties of lactoferrin, lysozyme, and whole milk and on the digestive resistance of lactoferrin and lysozyme.

METHODS

Flash-heated and unheated breastmilk aliquots from HIV-positive mothers in South Africa were "spiked" with Staphylococcus aureus and Escherichia coli and then cultured for 0, 3, and 6 hours. Lysozyme and lactoferrin activities were determined by lysis of Micrococcus luteus cells and inhibition of enteropathogenic E. coli, respectively, measured spectrophotometrically. Percentages of proteins surviving in vitro digestion, lactoferrin and lysozyme activity, and bacteriostatic activity of whole milk in heated versus unheated samples were compared.

RESULTS

There was no difference in rate of growth of E. coli or S. aureus in flash-heated versus unheated whole milk (p = 0.61 and p = 0.96, respectively). Mean (95% confidence interval) antibacterial activity of lactoferrin was diminished 11.1% (7.8%, 14.3%) and that of lysozyme by up to 56.6% (47.1%, 64.5%) by flash-heat. Digestion of lysozyme was unaffected (p = 0.12), but 25.4% less lactoferrin survived digestion (p < 0.0001).

CONCLUSIONS

In summary, flash-heat resulted in minimally decreased lactoferrin and moderately decreased lysozyme bioactivity, but bacteriostatic activity of whole milk against representative bacteria was unaffected. This suggests flash-heated breastmilk likely has a similar profile of resistance to bacterial contamination as that of unheated milk. Clinical significance of the decreased bioactivity should be tested in clinical trials.

Feasibility and safety of setting up a donor breastmilk bank in a neonatal prem unit in a resource limited setting: An observational, longitudinal cohort study

Background

The beneficial effects of human milk on decreasing rates of paediatric infections such as necrotizing enterocolitis (NEC) and sepsis have been clearly demonstrated. Donor breastmilk has been encouraged as the milk of choice when a mother's own breastmilk is not available. The objectives of this study were to assess feasibility of providing donor breastmilk to infants in a resource limited Neonatal Prem Unit (NPU). In addition we sought to determine whether donor breastmilk could be safely pasteurized and administered to infants without any adverse events.

Methods

Low birth weight infants < 1800 g and under 32 weeks gestational age were followed up in the NPU over a 3 week period; feeding data and morbidity data was collected in order to determine if there were any adverse events associated with donor breastmilk. Samples of pasteurized breastmilk were cultured to check for any bacterial contamination.

Results

191 infants met the inclusion criteria of whom 96 received their mother's own breastmilk. Of the 95 infants who were potentially eligible to receive donor milk, only 40 did in fact receive donor milk. There was no evidence of bacterial contamination in the samples analyzed, and no evidence of adverse events from feeding with donor breastmilk.

Conclusion

It is feasible to supply donor breastmilk to infants in an NPU in a resource limited setting, however staff needs to be sensitized to the importance of donor breastmilk to improve uptake rates. Secondly we showed that it is possible to supply donor breastmilk according to established guidelines with no adverse events therefore making it possible to prevent NEC and other side effects often associated with formula feeding of premature infants.

Current knowledge and future research on infant feeding in the context of HIV: basic, clinical, behavioral, and programmatic perspectives

In 2008, between 129,000 and 194,000 of the 430,000 pediatric HIV infections worldwide were attributable to breastfeeding. Yet in many settings, the health, economic, and social consequences of not breastfeeding would have dire consequences for many more children. In the first part of this review we provide an overview of current knowledge about infant feeding in the context of HIV. Namely, we describe the benefits and risks of breastmilk, the evolution of recommended infant feeding modalities in high-income and low-income countries in the last two decades, and contextualize the recently revised guidelines for infant feeding in the context of HIV current knowledge. In the second section, we suggest areas for future research on the postnatal prevention of mother-to-child transmission of HIV (PMTCT) in developing and industrialized countries. We suggest two shifts in perspective. The first is to evaluate PMTCT interventions more holistically, to include the psychosocial and economic consequences as well as the biomedical ones. The second shift in perspective should be one that contextualizes postnatal PMTCT efforts in the cascade of maternal health services. We conclude by discussing basic, clinical, behavioral, and programmatic research questions pertaining to a number of PMTCT efforts, including extended postnatal ARV prophylaxis, exclusive breastfeeding promotion, counseling, breast milk pasteurization, breast milk banking, novel techniques for making breast milk safer, and optimal breastfeeding practices. We believe the research efforts outlined here will maximize the number of healthy, thriving, HIV-free children around the world.

Heat treatment of expressed breast milk is a feasible option for feeding HIV-exposed, uninfected children after 6 months of age in rural Zimbabwe

In the context of a prevention of mother to child transmission of HIV program promoting exclusive breast-feeding (EBF) to 6 mo and offering HIV-PCR testing at approximately 6 mo, we ascertained the feasibility of expressing and heat-treating (EHT) all breast milk fed to HIV-exposed, uninfected infants following 6 mo of EBF. Twenty mother-baby pairs were enrolled from a hospital in rural Zimbabwe. Research nurses provided lactation, EHT, and complementary feeding counseling through 21 home visits conducted over an 8-wk period and collected quantitative and qualitative data on the mothers' EHT experiences, children's diets, and anthropometric measurements. Mothers kept daily logs of EHT volumes and direct breast-feeding episodes. Mothers successfully initiated and sustained EHT for 4.5 mo (range, 1-11 mo), feeding 426 +/- 227 mL/d (mean +/- SD). By wk 2 of follow-up, children were receiving EHT and Nutributter-enriched complementary foods that satisfied 100% of their energy requirements. During the 8-wk follow-up period, no growth faltering was experienced [changes in weight-for-age, weight-for-length, and length-for-age Z scores = +0.03 +/- 0.50; +0.77 +/- 1.59; and +0.02 +/- 0.85 (mean +/- SD), respectively]. Stigma was not a major deterrent, likely due to a social marketing campaign for EBF that promoted EHT as a practice to sustain breast-feeding for all women. This study provides evidence that resource-poor rural women can initiate and sustain EHT given family and health systems support. EHT provides a strategy for improving the diets of HIV-exposed but uninfected children after direct breast-feeding has ceased.

Vitamin content of breast milk from HIV-1-infected mothers before and after flash-heat treatment

BACKGROUND

World Health Organization advocates heat treatment of expressed breastmilk (EBM) as one method to reduce postnatal transmission of human immunodeficiency virus (HIV) in developing countries. Flash-heat is a simple heat treatment method shown to inactivate cell-free HIV.

OBJECTIVE

To determine the effect of flash-heat on vitamin content of milk.

METHODS

Fresh EBM was collected from 50 HIV+ mothers in Durban, South Africa. Mothers washed their hands and then manually expressed 75-150 mL EBM into sterile jars. Milk was aliquoted to unheated controls or flash-heat (50 mL EBM in a glass jar heated in a 450-mL water jacket in an aluminum pan until water boiled, then EBM removed) simulating field conditions with an open flame. Samples were stored at -70 degrees C and then analyzed for the effect of flash-heat on vitamins [A, ascorbic acid, riboflavin (B2), pyridoxal-5-phosphate (B6), folate, and B12].

RESULTS

Vitamin A was not significantly affected by flash-heat and vitamins B12 and C and folate increased significantly. Vitamins B2 and B6 were decreased to 59% (95% confidence interval 44 to 81) and 96% (95% confidence interval 92 to 99), respectively, of that found in unheated milk.

CONCLUSIONS

The percentage remaining after flash-heat suggests that most vitamin concentrations are retained after heating. Flash-heat may be a practical and nutritious infant feeding method for mothers in developing countries.

Flash-heat inactivation of HIV-1 in human milk: a potential method to reduce postnatal transmission in developing countries

BACKGROUND

Up to 40% of all mother-to-child transmission of HIV occurs by means of breast-feeding; yet, in developing countries, infant formula may not be a safe option. The World Health Organization recommends heat-treated breast milk as an infant-feeding alternative. We investigated the ability of a simple method, flash-heat, to inactivate HIV in breast milk from HIV-positive mothers.

METHODS

Ninety-eight breast milk samples, collected from 84 HIV-positive mothers in a periurban settlement in South Africa, were aliquoted to unheated control and flash-heating. Reverse transcriptase (RT) assays (lower detection limit of 400 HIV copies/mL) were performed to differentiate active versus inactivated cell-free HIV in unheated and flash-heated samples.

RESULTS

We found detectable HIV in breast milk samples from 31% (26 of 84) of mothers. After adjusting for covariates, multivariate logistic regression showed a statistically significant negative association between detectable virus in breast milk and maternal CD4+ T-lymphocyte count (P=0.045) and volume of breast milk expressed (P=0.01) and a positive association with use of multivitamins (P=0.03). All flash-heated samples showed undetectable levels of cell-free HIV-1 as detected by the RT assay (P<0.00001).

CONCLUSIONS

Flash-heat can inactivate HIV in naturally infected breast milk from HIV-positive women. Field studies are urgently needed to determine the feasibility of in-home flash-heating breast milk to improve infant health while reducing postnatal transmission of HIV in developing countries.