Breakthrough study shows synbiotic effective in prevention of sepsis in Indian babies

A team of scientists has discovered that a combination of probiotics and prebiotics was very effective in lowering the risk of developing sepsis - a life-threatening condition where infections cause systemic inflammation, restricted blood flow and organ failure - in 4,557 babies enrolled in a study in India. Sepsis is one of the biggest killers of newborn babies, ending around 600,000 young lives every year. The discovery has been hailed as one of the first big successful trials involving probiotics.

To find suitable strains of probiotics, the team, led by Pinaki Panigrahi at the University of Nebraska Medical Center, decided not to just test probiotics that were available on shelves, but instead collected stool samples from healthy volunteers and screened the microbes within for those that could stick to human cells, and could prevent disease-causing bacteria from doing so. They ended up with a strain called Lactobacillus plantarum ATCC strain 202195, which colonized infant guts successfully and stayed there for up to four months. The scientists' large trial was then launched.

Their product contained a strain of Lactobacillus plantarum, chosen for its ability to attach to gut cells and "colonize the infant gut over the longer term." The team also added a sugar, chosen to nourish the microbe and give it a foothold when it enters a baby's gut. The combination of probiotics and prebiotics, a synbiotic, was found to be very effective.

The effect was twice as large as the team had previously expected, even though the infants took doses of the synbiotic daily for just one week. And given the clear evidence of benefits, independent experts who were monitoring the study decided to stop the trial early because it would have been unethical to continue depriving half the newborns of the treatment. Thus, Panigrahi stopped at 4,557 babies after originally planning to enroll 8,000 babies into the study. But the number was still large compared to previous studies.

Probiotics trials have been criticized in the past for being too small. Those that looked at sepsis, for example, usually involved just 100 to 200 babies, making it hard to know whether any beneficial effects were the result of random chance. The biggest trial to date included 1,315 infants; Panigrahi's study is over three times bigger. "[It] exemplifies how intervention research should be done," writes Daniel Tancredi from the University of California, Davis, in a commentary that accompanies the paper.

However, the findings have limits. "The current trial identifies a single synbiotic preparation as protective in a term or late-preterm population in the developing world, but other populations may require different formulations. Also, in our study cohort, only a small subset of cases identified by pediatricians as pSBI were of bacterial origin," the study says.

Interestingly, the researchers note that if future studies suggest they are largely viral, "a major paradigm shift in our assumptions of probiotic-mediated protection will be required."

Additionally, the researchers note that the study was performed in a research setting "under stringent daily follow-up at home." In areas that are not as easily accessible, attention will have to be given to the maintenance of a cold chain and the final distribution of formulations to all newborns in a culturally acceptable manner.