Infant gut bacteria tied to lower malaria risk in small Congo study
University of Florida researchers say gut microbes at 6 weeks appeared to predict malaria infections during babies’ first year, but larger studies are needed.
By Priya Raghavan · Science Reporter
3 min read
Infants in a small study in the Democratic Republic of Congo were less likely to develop malaria in their first year if they had healthier gut microbiomes at 6 weeks old, University of Florida researchers reported. The finding points to a possible early-life factor in malaria risk, though the researchers said it is too soon to recommend probiotics or other treatments.
The study followed 47 mother-infant pairs in collaboration with HEAL Africa Hospital in eastern Congo, according to the University of Florida. Researchers collected stool samples during the babies’ first year and tracked whether the infants contracted malaria.
The work was published in Frontiers in Cellular and Infection Microbiology. The University of Florida said the Democratic Republic of Congo accounts for more than 10% of global malaria deaths, and malaria kills more than 600,000 people a year, mostly children in sub-Saharan Africa.
What researchers found
Julie Moore, a professor of infectious diseases in the University of Florida College of Veterinary Medicine and senior author of the report, said the composition of an infant’s gut microbiome at 6 weeks was able to predict whether that child later had malaria during the first year of life.
Babies who did not develop malaria were more likely to carry bacteria associated with typical healthy infant development, the university said. Those microbes included types often found in breastfed babies, including Bifidobacterium, according to Moore.
Infants who later had malaria showed higher levels of bacteria more commonly associated with inflammation, the researchers reported. Moore cited Klebsiella as an example of a microbe linked with a less healthy gut profile.
The University of Florida said the project grew from work by Moore and professors Christopher Dutton and Connie Mulligan. Mulligan, a genetic anthropologist, has worked with HEAL Africa Hospital since 2010, while Dutton and Moore had studied links between the microbiome and malaria susceptibility in animal models.
Why the link remains uncertain
The researchers said the results fit with broader evidence that gut microbes can influence immune development. They suspect beneficial bacteria may help shape the infant immune system, while less healthy microbial communities may be tied to greater vulnerability to infection.
Moore cautioned that scientists still do not understand well how the infant gut microbiome affects outcomes after infection. The study also did not prove that gut bacteria directly protected babies from malaria.
One complicating factor was bed-net use. The University of Florida said babies who slept under insecticide-treated nets were also less likely to get malaria, making it harder to separate the role of gut microbes from other protective measures.
Because of that, the researchers said larger studies will be needed to estimate how much of the difference in malaria risk can be explained by the microbiome itself. Moore said probiotic use in malaria-endemic areas is an idea for future research, but not a recommendation based on the current findings.
Moore said she would like follow-up work to examine immune development in the infants and test whether differences in immune responses over the first year match differences in gut bacteria.
This story draws on original reporting from Medical Xpress.