Can Probiotics Treat or Prevent Bacterial Infections?

• Antibiotic resistance is a serious public health threat around the world.

• Early evidence suggests certain probiotics may be able to prevent or even help treat bacterial infections in specific cases, but far more research is needed.

• Experts say reducing dependence and misuse of antibiotics is important to keep antibiotics effective in the meantime.
  

Antibiotics are the most effective medicines we have to stop bacterial infections, but an increase in resistant bacteria, or superbugs, is threatening to reduce the efficacy of these drugs. In 2021, the World Health Organization called antimicrobial resistance one of the top 10 global health threats.

But some researchers suggest that probiotics—which promote the growth of certain “good” bacteria—might be a potential solution in fighting superbugs.

According to Natalie Ma, PhD, a synthetic biologist and entrepreneur, antibiotics are like a forest fire in the sense that they usually kill all microbes, both good and bad, but people often take probiotics to replace the good microbes lost after taking antibiotics.

“There’s not as strong scientific evidence that [probiotics] work, partly because it’s harder to measure, but there’s some evidence that they’re more likely to succeed after taking antibiotics,” she said. “Going back to the forest analogy, it’s a lot easier to plant a tree or introduce a new species after a forest fire, because there’s lots of space and many ecological roles to fill.”

Related:Prebiotic vs. Probiotic vs. Postbiotic: Chart and Gut Facts

Research on the effectiveness of probiotics—especially as treatment or prevention of bacterial infections—is minimal. But a small study published in The Lancet found that a probiotic was able to reduce Staphylococcus aureus, a bacterium that causes skin and soft tissue infections, in human beings.

According to the study’s coauthor Michael Otto, PhD, the researchers set out to prevent infections by S. aureus, because this type of germ is often resistant to antibiotics and there’s no working S. aureus vaccine.

The trial results suggest that the oral form of Bacillus “may be of use for patients suffering from chronic forms of S. aureus infections,” where long-term antibiotic use would bring about severe side effects, Otto said.

Since Bacillus probiotic spores are generally safe and they don’t harm the microbiome, they can be taken for as long as is needed, he explained.

While the results are promising, Otto said the study is very specific to the Bacillus-S. aureus interaction. He added that the alleged benefits of the often ill-defined probiotic mixtures on the supplement market often lack scientific evidence on how the components are supposed to work.

Related:The Best Probiotic Supplements for IBS

Can Commercial Probiotics Fight Bacterial Infections?

Otto and his team are planning to screen currently commercially available Bacillus probiotics on the market for their potency. According to their initial results, he said, not all strains on the market produce the molecules that are key to the desired effect on S. aureus.

Another study, published in The New England Journal of Medicine in 2022, found that a standardized probiotic may be able to effectively prevent a C. difficile infection. While there is some debate on the subject, a wide variety of probiotics has been tested and used to prevent or treat C. diff, including Saccharomyces boulardii, Lactobacillus rhamnosus GG (LGG) and other lactobacilli, and probiotic mixtures.

Related:What Is Lactobacillus Acidophilus?

While there’s no standardized clinical use of probiotics in infections, a 2020 review suggests that probiotics show promising antimicrobial activity.

Oladele Ogunseitan, PhD, MPH, a professor of population health and disease prevention at the University of California, said that probiotics can help “restore balance to the species diversity of the human microbiome.” If they’re proven effective, they could help “prevent disease symptoms caused by imbalance or dominance of pathogenic and antibiotic-resistant bacteria,” he said.

However, Ogunseitan said we should be wary of any claim that probiotics are the solution to antibiotic-resistant infections, because far more research is needed. We don’t understand enough about bacteria-to-bacteria interactions in the human system to promote sustainable approaches that work for every patient, he added.

“I expect that in the next few years, we will be seeing evidence-based probiotic interventions,” Ogunseitan said. “I would hope that the FDA will regulate these, just as with any medication, because there is also potential for misuse and side effects.”

In the meantime, Otto said reducing antibiotic dependence and overuse will help limit the spread of superbug infections. That way, existing antibiotics will still work when we need them.

Read Next:The Surprising Health Benefits of Fermented Foods

Research has not proven that probiotics can cure or prevent bacterial infections. If you think you may have a bacterial infection, you should always see your healthcare provider and take the antibiotics prescribed.