An international team led by UC Davis researchers has found that mothers in sub-Saharan Africa could successfully follow a protocol for flash-heating breastmilk to reduce transmission of human immunodeficiency virus (HIV) – the virus that causes Aids – to their infants.
Flash-heating breastmilk is recommended by the World Health Organization (WHO) for HIV-infected mothers during times of increased transmission risk. The technique involves expressing breastmilk into a glass jar that is placed in a small pot of water and heated until the water boils.
How the research was done
UC Davis research shows that women in Dar es Salaam, Tanzania, could flash heat their breast milk to reduce the chances of HIV transmission.
Previous research from UC Davis and UC Berkeley showed that this process inactivates HIV in breastmilk, while retaining the milk's nutritional and infection-fighting properties. But whether or not women in poor countries would be willing and able to successfully use the technique had not been established.
Published in the Journal of Acquired Immune Deficiency Syndromes, the current study showed that women in Dar es Salaam, Tanzania - a resource-poor urban area - could follow the protocol consistently over an average of about 10 weeks, with some mothers utilising the method up to a full year.
HIV positive and breastfeeding
"More women with HIV than we anticipated were willing and able to flash heat their breastmilk and make it safe despite very limited resources," said Caroline Chantry, professor of paediatrics at UC Davis Children's Hospital and lead author of the study. "These findings show that the World Health Organization's recommendations are feasible in a real-world setting."
Even in the absence of HIV medications, HIV-positive mothers in resource-poor regions are advised to exclusively breastfeed their children for six months. When compared to partial breastfeeding, exclusive breastfeeding can reduce the chances of mother-to-child HIV transmission during the first months of life.
Physicians believe this is because mixed feeds increase the likelihood of allergens or contaminants that compromise the epithelial lining of a baby's digestive tract, making it easier for HIV to pass through. But while longer-term breastfeeding substantially increases the likelihood of HIV transmission, early cessation of breastfeeding is associated with high morbidity and mortality in developing areas.
"It's a very high-risk period for diseases and deaths from gastrointestinal infections," Chantry said. "Flash heating can help women provide nutrient and antibody-rich breastmilk to their infants beyond six months of age and reduce the possibility of HIV transmission at the same time."
To find out if women would use the protocol, Chantry and her team enrolled 101 HIV-infected mothers and their infants in the study: 86 infants were still alive and participating in the study at five months of age when the infants were tested for HIV. Of these infants, 72 were HIV negative, and more than half of their mothers chose to flash heat their breastmilk.
Success of flash- heating breast milk
Peer counsellors provided the necessary equipment and then visited the mothers weekly to offer instructions on flash heating and observe how well they followed the protocol, which included washing their hands, cleaning utensils, bringing the milk to the correct temperature (typically 72.9° C) and then allowing it to cool before feeding it to children with a spoon or cup.
"These mothers succeeded in flash heating with only modest support from trained peer counsellors rather than professional health-care providers," Chantry said. "This method is inexpensive in terms of costs and workforce and could be sustainable in resource-limited settings."
Untreated and flash-heated breastmilk samples were collected every two weeks for bacterial analysis. The flash-heated milk was found to be bacteriologically safe.
Chantry said that the study sets the stage for a clinical trial to determine whether flash heating improves infant-health outcomes and to evaluate the cost-effectiveness of health improvements in addition to averted HIV infections.
"Our focus is on improving both HIV-free 'thrival' as well as HIV-free survival," Chantry said. "WHO has also called for research on the feasibility of supporting and sustaining this practise on a large scale."
In addition to Chantry, study authors were Sera Young, Janet Peerson and Kathryn Dewey of UC Davis; Waverly Rennie, Monica Ngonyani, Clara Mashio and Margaret Nyambo of University Research Company, Dar es Salaam, Tanzania; Kiersten Israel-Ballard and Peggy Koniz-Booher of PATH, Seattle; Mecky Matee of Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania; and Deborah Ash of Academy for Educational Development, Dar es Salaam, Tanzania.
"Feasibility of Using Flash-Heated Breastmilk as an Infant Feeding Option for HIV-Exposed, Uninfected Infants after 6 Months of Age in Urban Tanzania" was funded by the National Institutes of Health.
(EurekAlert, May 2012)
Preventing mother-to-baby transmission