Epidemiologist Eduardo Villamor of the University of Michigan School of Public Health says transmission of HIV through breastfeeding happens because breast milk carries viral particles that the baby ingests. Supplementing HIV-positive women with vitamin A and beta-carotene appears to increase the amount of the virus in milk.
This may be partly because the same nutrients raise the risk of developing subclinical mastitis, an inflammatory condition which causes blood plasma to leak into the mammary gland and viral particles to then leak into the milk, he says.
Villamor's findings appear in two separate articles in the American Journal of Clinical Nutrition and the Journal of Nutrition. The results are significant because they provide biological explanations for a previous report that supplementation with these nutrients increased chances of mother-to-child HIV transmission.
"So there are now strong arguments to consider the implications of supplementation to pregnant or lactating women who are HIV-positive," said Villamor, associate professor of epidemiology and environmental health sciences. "It does not look like it's a safe intervention for them."
Mother-to-child HIV transmission is a huge problem in developing countries where HIV is prevalent, Villamor said. In 2008 alone, there were 430,000 new infections and more than 95 percent of those resulted from mother-to-child transmission. Most were in sub-Saharan Africa.
In one of the studies, 1,078 HIV-infected women were divided into four groups. The test groups received either 5,000 IU of vitamin A and 30 mg of beta-carotene everyday during gestation and the lactation period, or a control regimen. The dose for beta-carotene was higher than the amount usually provided by the diet, according to Villamor. Smaller doses might not have the same effect.
Villamor said tests trying to separate the effects of each nutrient showed that beta-carotene seemed to increase the amount of HIV in breast milk independent of vitamin A, but an effect of vitamin A alone cannot be ruled out. The findings are potentially controversial because vitamin A is an important supplement for postpartum women in countries where HIV infection is highly prevalent, but supplementation programs may not take into account a woman's HIV status.
"The takeaway is that daily supplementation of HIV-infected pregnant or lactating women with vitamin A and beta-carotene at the doses tested is probably not safe and efforts need to be strengthened on preventing mother-to-child transmission through other interventions such as anti-retroviral regimens," Villamor said.
Study 1 ("Effect of Vitamin Supplements on HIV Shedding in Breast Milk"): www.ajcn.org/cgi/search?fulltext=Effect+of+vitamin+supplements+on+HIV+shedding+in+breast+milk&submit=yes&x=12&y=8
Study 2 ("Vitamin Supplementation Increases Risk of Subclinical Mastitis in HIV-Infected Women"): http://jn.nutrition.org/cgi/search?fulltext=Vitamin+Supplementation+Increases+Risk+of+Subclinical+Mastitis+in+HIV-Infected+Women&submit=yes&x=15&y=11
Eduardo Villamor: www.sph.umich.edu/iscr/faculty/profile.cfm?uniqname=villamor
Department of Epidemiology: www.sph.umich.edu/epid
Department of Environmental Health Sciences: www.sph.umich.edu/ehs
School of Public Health: www.sph.umich.edu
The University of Michigan School of Public Health has been promoting health and preventing disease since 1941, and is ranked among the top public health schools in the nation. Whether making new discoveries in the lab or researching and educating in the field, SPH faculty, students and alumni are deployed around the globe to promote and protect our health.
Laura Bailey | EurekAlert!
Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign
Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences