Hepatitis B viral markers in banked human milk before and after Holder pasteurization

Viruses and Human Milk: Transmission or Protection?

Human milk (HM) is considered the best source of nutrition for infant growth and health. This nourishment is unique and changes constantly during lactation to adapt to the physiological needs of the developing infant. It is also recognized as a potential route of transmission of some viral pathogens although the presence of a virus in HM rarely leads to a disease in an infant. This intriguing paradox can be explained by considering the intrinsic antiviral properties of HM. In this comprehensive and schematically presented review, we have described what viruses have been detected in HM so far and what their potential transmission risk through breastfeeding is. We have provided a description of all the antiviral compounds of HM, along with an analysis of their demonstrated and hypothesized mechanisms of action. Finally, we have also analyzed the impact of HM pasteurization and storage methods on the detection and transmission of viruses, and on the antiviral compounds of HM. We have highlighted that there is currently a deep knowledge on the potential transmission of viral pathogens through breastfeeding and on the antiviral properties of HM. The current evidence suggests that, in most cases, it is unnecessarily to deprive an infant of this high-quality nourishment and that the continuation of breastfeeding is in the best interest of the infant and the mother.

Hepatitis B Viral Markers in the Human Milk of HBsAg-Positive Mothers: An Observational Study

BACKGROUND

Quantification of viral antigens and viral loads in human milk samples from mothers infected with hepatitis B virus is largely unknown.

RESEARCH AIM

The aim of the study was to quantitatively measure the levels of viral antigens and deoxyribonucleic acid of hepatitis B virus in human milk from mothers infected with hepatitis B virus.

METHODS

Fifty-five pairs of milk and serum samples from mothers with positive hepatitis B surface antigen, including 11 hepatitis B e antigen positive, were quantitatively tested to measure viral antigens by microparticle enzyme immunoassay and viral loads by real-time polymerase chain reaction assay.

RESULTS

The median level of hepatitis B surface antigen in the human milk samples of mothers with positive or negative hepatitis B e antigen was each lower than that in the sera, respectively (1.10 vs. 4.32 log₁₀ IU/ml, t = 10.693, p < .001; -0.77 vs. 2.53 log₁₀ IU/ml, t = -25.135, p < .001). The titers of hepatitis B surface antigen or hepatitis B e antigen in the human milk samples were each correlated with that in maternal serum. The detectable level of deoxyribonucleic acid of hepatitis B virus in human milk ranged from 1.42-5.27 log₁₀ IU/ml, whereas that in maternal sera was 1.44-8.66 log₁₀ IU/ml. The viral level in human milk was not correlated with that in maternal circulation.

CONCLUSION

The present study data illustrate the relatively low titers of viral markers in the milk of mothers with positive hepatitis B surface antigen.

Inhibition of In Vitro Infection of Hepatitis B Virus by Human Breastmilk

Despite the presence of hepatitis B virus (HBV) in the human breastmilk of mothers infected with HBV, it has been shown that breastfeeding does not increase the risk of mother-to-child transmission (MTCT) of HBV. We tested the hypothesis that human breastmilk may contain active components that bind to HBV and inhibit the infectivity of HBV. The results show that human whey significantly inhibited the binding of the hepatitis B surface antigen (HBsAg) to its antibodies in competitive inhibition immunoassays. The far-western blotting showed that HBsAg bound to a protein of 80 kD in human whey, which was identified as lactoferrin by mass spectrometry. Competitive inhibition immunoassays further demonstrated that both human lactoferrin and bovine lactoferrin bound to HBsAg. Human whey, human lactoferrin, and bovine lactoferrin each significantly inhibited the infectivity of HBV in vitro. Our results indicate that human breastmilk can bind to HBsAg and inhibit the infectivity of HBV, and the active component is lactoferrin. The findings may explain the reason that breastfeeding has no additional risk for MTCT of HBV, although human breastmilk contains HBV. Our study provides experimental evidence that HBV-infected mothers should be encouraged to breastfeed their infants

Testing the effects of processing on donor human Milk: Analytical methods

Holder pasteurization is the current recommended method for donor human milk treatment. This method effectively eliminates most life-threatening contaminants in donor milk, but it also greatly reduces some of its biological properties. Consequently, there is a growing interest for developing novel processing methods that can ensure both microbial inactivation and a higher retention of the functional components of donor milk. Our aim was to offer a comprehensive overview of the analytical techniques available for the evaluation of such methods. To suggest an efficient workflow for the analysis of processed donor milk, a safety analytical panel as well as a nutritional value and functionality analytical panel are discussed, together with the principles, benefits, and drawbacks of the available techniques. Concluding on the suitability of a novel method requires a multifactorial approach which can be achieved by a combination of analytical targets and by using complementary assays to cross-validate the obtained results.

Chronic hepatitis B in pregnant women: Current trends and approaches

Chronic hepatitis B (CHB) is a significant public health problem worldwide. The aim of the present review is to summarize the actual trends in the management of CHB in pregnant women. The prevalence of hepatitis B virus (HBV) infection in pregnant women is usually comparable to that in the general population in the corresponding geographic area. All women have to be screened for hepatitis B surface antigen (HBsAg) during pregnancy. Additional examinations of pregnant women with CHB may include maternal hepatitis B e antigen, HBV viral load, alanine aminotransferase level, and HBsAg level. The management of pregnancy depends on the phase of the HBV infection, which has to be determined before pregnancy. In women of childbearing age with CHB, antiviral therapy can pursue two main goals: Treatment of active CHB, and vertical transmission prevention. During pregnancy, tenofovir is the drug of choice in both cases. A combination of hepatitis B immunoglobulin and vaccine against hepatitis B should be administered within the first 12 h to all infants born to mothers with CHB. In such cases, there are no contraindications to breastfeeding.

Development and evaluation of formal guidelines for donor selection for human milk banks

AIM

Donor selection for milk banks is essential to ensure the safety and nutritional quality of the donor milk, and to ensure that the prospective donor and her breastfeeding infant do not come to harm through donating. Australian Red Cross Lifeblood Milk went through a robust process to develop a set of criteria for the selection and screening of potential breast milk donors, which included development of a Donor Questionnaire (DQ), supported by a formal set of Guidelines for the Selection of Milk Donors. Key screening questions from the DQ were made available to prospective donors to self-screen prior to the formal assessment process. The aim of this study was to review the outcomes of milk donor screening at Lifeblood Milk.

METHODS

We reviewed the outcomes of our donor screening process over the first 12-months (July 2018-June 2019) of operations.

RESULTS

A total of 50 out of 327 donors who responded to the self-screening questions were not able to proceed further; 201 donors were formally screened using the DQ and Guidelines for the Selection of Milk Donors, with 9 of 201 deferred based on their responses. An additional two donors were deferred (failed phlebotomy (n = 1) and reactive infectious disease serology (n = 1)), with 190 of 201 (95%) of prospective donors accepted after screening.

CONCLUSIONS

Our experience highlighted international differences in practice between milk banks and lack of strong research to inform milk donor selection. Making a set of key screening questions available to donors for self-screening resulted in a high acceptance rate (95%) for donors who began the formal screening process. Further work is needed to better understand the impact of deferral on prospective milk donors.

Chronic hepatitis B infection and non-hepatocellular cancers: A hospital registry-based, case-control study

Background

Prior epidemiological evidences suggest that hepatitis B virus (HBV) infection is linked to cancers other than hepatocellular carcinoma. This prospective hospital registry-based case-control study aimed to investigate the sero-epidemiological association between chronic HBV infection and various types of cancer.

Methods

95,034 patients with first-diagnosed non-hepatocellular malignancy in a tertiary hospital between 2007 and 2014; and 118,891 non-cancer individuals as controls from a health promotion center were included. Cases and controls were compared for HBV surface antigen (HBsAg) positivity by conditional regression with adjustment for age, hypertension, diabetes, body mass index, alcohol consumption, smoking status and cholesterol level in both genders.

Results

An analysis of matched data indicated significant associations of HBV infection with lymphoma (adjusted odds ratio[AOR] 1.53 [95% CI 1.12–2.09] in men and 3.04 [1.92–4.82] in women) and biliary cancer (2.59[1.98–3.39] in men and 1.71[1.16–2.51] in women). Cervical (1.49[1.11–2.00]), uterine (1.69[1.09–2.61]), breast (1.16[1.02–1.32]), thyroid (1.49[1.28–1.74]), and lung cancers (1.79[1.32–2.44]) in women; and skin cancer (5.33[1.55–18.30]) in men were also significantly related to HBV infection.

Conclusions

Chronic HBV infection is associated with several malignant disorders including lymphoma, and biliary, cervical, uterine, breast, thyroid, lung, and skin cancers. Our findings may offer additional insights into the development of these neoplasms and may suggest the need to consider HBV screening in cancer patients and cancer surveillance in HBV-infected subjects.

Ebola Virus and Marburg Virus in Human Milk Are Inactivated by Holder Pasteurization

BACKGROUND

Potential donors of human milk are screened for Ebola virus (EBOV) using standard questions, but testing for EBOV and Marburg virus (MARV) is not part of routine serological testing performed by milk banks. Research aim: This study tested the hypothesis that EBOV would be inactivated in donor human milk (DHM) by standard pasteurization techniques (Holder) used in all North American nonprofit milk banks.

METHODS

Milk samples were obtained from a nonprofit milk bank. They were inoculated with EBOV (Zaire strain) and MARV (Angola strain) and processed by standard Holder pasteurization technique. Plaque assays for EBOV and MARV were performed to detect the presence of virus after pasteurization.

RESULTS

Neither EBOV nor MARV was detectable by viral plaque assay in DHM or culture media samples, which were pasteurized by the Holder process.

CONCLUSION

EBOV and MARV are safely inactivated in human milk by standard Holder pasteurization technique. Screening for EBOV or MARV beyond questionnaire and self-deferral is not needed to ensure safety of DHM for high-risk infants.

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.

Prevention strategies for blood-borne viruses-in the Era of vaccines, direct acting antivirals and antiretroviral therapy

Blood-borne viruses, such as hepatitis B virus, hepatitis C virus, human immunodeficiency virus, and the facultative blood-borne hepatitis E virus, are considered a major public health problem given that they are accountable for millions of deaths each year. Treatment options, including effective vaccine design, development of antiviral strategies and the implementation of antiretroviral therapy have improved substantially over the last couple of years and contribute to successful treatment and prevention of these infectious diseases. In this review, we summarise the current knowledge and concepts in prevention of transmission of these blood-borne viruses.

Hepatitis B virus mother-to-child transmission among HIV-infected women receiving lamivudine-containing antiretroviral regimens during pregnancy and breastfeeding

The study included 309 HIV-infected pregnant women receiving a lamivudine-containing antiretroviral regimen from week 25 of gestational age until 6 months postpartum, during breastfeeding. Twenty-seven of them (8.7%) were hepatitis B virus surface antigen (HBsAg) positive; at baseline, hepatitis B virus (HBV) DNA levels >3 log(10) IU/mL (with a median level of 6.2 log(10) IU/mL) were found in 10 women, who at one, three and six months postpartum had median levels of 5.2 log(10) IU/mL, 4.5 log(10) IU/mL and 2.8 log(10) IU/mL, respectively. Twenty-four of the 30 breast milk samples evaluated had undetectable HBV DNA and the other six had values between 15 and 155 IU/mL. Median lamivudine concentrations were 1070 ng/mL in serum and 684 ng/mL in breast milk. Among the 24 HBV-exposed children with available samples, 16 always tested negative, four had a transient infection, one had an undetermined status and three (12.5%) first tested positive at Month 12 or Month 24. Among the children born to the HBV-uninfected mothers of the same cohort, the rate of HBsAg positivity at 12-24 months was 2% (4/196). Our finding of the absence of significative levels of HBV DNA in the breast milk of co-infected mothers supports the present recommendations for breastfeeding in HBV-infected women. Horizontal transmission can be hypothesized for the infections detected in children at 12-24 months. Children born to HBV-positive mothers remained at higher risk of postnatal HBV acquisition compared to those born to HBV-negative women.

Determination of Dornic acidity as a method to select donor milk in a milk bank

BACKGROUND

Dornic acidity may be an indirect measurement of milk's bacteria content and its quality. There are no uniform criteria among different human milk banks on milk acceptance criteria. The main aim of this study is to report the correlation between Dornic acidity and bacterial growth in donor milk in order to validate the Dornic acidity value as an adequate method to select milk prior to its pasteurization.

MATERIALS AND METHODS

From 105 pools, 4-mL samples of human milk were collected. Dornic acidity measurement and culture in blood and McConkey's agar cultures were performed. Based on Dornic acidity degrees, we classified milk into three quality categories: top quality (acidity <4°D), intermediate (acidity between 4°D and 7°D), and milk unsuitable to be consumed (acidity ≥ 8°D). Spearman's correlation coefficient was used to perform statistical analysis.

RESULTS

Seventy percent of the samples had Dornic acidity under 4°D, and 88% had a value under 8°D. A weak positive correlation was observed between the bacterial growth in milk and Dornic acidity. The overall discrimination performance of Dornic acidity was higher for predicting growth of Gram-negative organisms. In milk with Dornic acidity of ≥ 4°D, such a measurement has a sensitivity of 100% for detecting all the samples with bacterial growth with Gram-negative bacteria of over 10(5) colony-forming units/mL.

CONCLUSIONS

The correlation between Dornic acidity and bacterial growth in donor milk is weak but positive. The measurement of Dornic acidity could be considered as a simple and economical method to select milk to pasteurize in a human milk bank based in quality and safety criteria.

Breastfeeding is not a risk factor for mother-to-child transmission of hepatitis B virus

Background

Many clinicians do not encourage breastfeeding in hepatitis B virus (HBV) carriers, since HBV DNA can be detected in breast milk and breast lesions may increase exposure of infants to HBV. The aim of this study was to determine whether breastfeeding may add risk for perinatal HBV transmission.

Methodology/Principal Findings

Totally 546 children (1–7-year-old) of 544 HBV-infected mothers were investigated, with 397 breastfed and 149 formula-fed; 137 were born to HBeAg-positive mothers. All children had been vaccinated against hepatitis B but only 53.3% received hepatitis B immune globulin (HBIG). The overall prevalence of HBsAg+, HBsAg−/anti-HBc+, and anti-HBs (≥10 mIU/ml) in children was 2.4%, 3.1%, and 71.6% respectively. The HBsAg prevalence in breast- and formula-fed children was 1.5% and 4.7% respectively (P = 0.063); the difference was likely due to the higher mothers' HBeAg-positive rate in formula-fed group (formula-fed 49.0% vs. breastfed 15.9%, P<0.001). Further logistic regression analyses showed that breastfeeding was not associated with the HBV infection in the children, adjusting for the effect of maternal HBeAg status and other factors different between the two groups.

Conclusions/Significance

Under the recommended prophylaxis, breastfeeding is not a risk factor for mother-to-child transmission of HBV. Therefore, clinicians should encourage HBV-infected mothers to breastfeed their infants.

Field and laboratory methods in human milk research

Human milk is a complex and variable fluid of increasing interest to human biologists who study nutrition and health. The collection and analysis of human milk poses many practical and ethical challenges to field workers, who must balance both appropriate methodology with the needs of participating mothers and infants and logistical challenges to collection and analysis. In this review, we address various collection methods, volume measurements, and ethical considerations and make recommendations for field researchers. We also review frequently used methods for the analysis of fat, protein, sugars/lactose, and specific biomarkers in human milk. Finally, we address new technologies in human milk research, the MIRIS Human Milk Analyzer and dried milk spots, which will improve the ability of human biologists and anthropologists to study human milk in field settings.

[Hepatitis B prevalence and risk factors in Morocco]

AIM

The aim of this study was to determine the prevalence of hepatitis B and the risk factors in Morocco.

STUDY DESIGN

A total number of 16,634 individuals were screened for HBsAg using the Murex HBsAg Version 3 assay and were interviewed using a structured standard questionnaire to collect information about risk factor.

RESULTS

Two hundred seventy-six subjects were positive for HBsAg, the prevalence of HBV infection was 1.66%. Using a structured standard questionnaire we reported that sexual behaviours (43.84%) are among the main risk factors for HBV transmission.

CONCLUSION

This study indicates that the prevalence of HBsAg in Morocco is currently estimated at 1.66% in the active population. The risk factors for HBV infection identified here indicate that prevention is the most cost-effective method for successfully controlling HBV infection, so vaccination remains the best way to control this infection and its related complications.

Breastfeeding and chronic HBV infection: Clinical and social implications

Mother-to-child transmission of hepatitis B virus (HBV) is among the most important causes of chronic HBV infection and is the commonest mode of transmission worldwide. Currently, the presence of HBsAg, HBeAg and HBV DNA in breast milk is confirmed. Several studies have reported that breastfeeding carries no additional risk that might lead to vertical transmission. Beyond some limitations, the surveys have not demonstrated any differences in HBV transmission rate regarding feeding practices in early childhood. Promotion of breastfeeding is substantial, especially for low-income individuals and regions with uncertain, unfeasible, and unsafe water supplies. Lactoferrin, minimal inflammation or activation within the infant gut during exclusive breastfeeding, and nonspecific biological molecules in the milk are identified as major factors of breast-milk defense. This review discusses preemptive antiviral therapy during pregnancy and lactation. Long-term follow up of breast-milk HBV concentrations and correlation with serum viral load; nucleos(t)ide analogue concentrations in breast milk in HBV-positive mothers in the setting of chronic HBV infection; safety of antiviral therapy during pregnancy and lactation; and the difference in viral load in the milk in exclusive or non-exclusive breastfeeding are still open questions. The paper reviews the current data and outlines the course of further investigation into this often underestimated issue.