Manipulating gut microbes may reduce intestinal parasitic infections

The kinds of microbes living in the gut influences the severity and recurrence of parasitic worm infections, researchers have found.

According to the World Health Organisation, about one quarter of the world's population, over 1.5 billion people, is infected with parasitic worms called helminths. These worm infections are most common in tropical and subtropical areas with poor sanitation.

In particular, gut bacteria associated with increased inflammation are linked to healthy uninfected individuals, perhaps because this type of inflammatory environment makes it harder for the worms to establish themselves in the gut, Xinhua news agency reported.

"People who have sustained infections or who experience multiple infections have a different microbiome to start with compared with those who do not have as much trouble with infection," said senior author Makedonka Mitreva, associate professor at the Washington University School of Medicine in the US.

In the study, published online in the journal Microbiome, researchers identified 12 microbes associated with worm-infected individuals and one type of bacteria associated with uninfected individuals.

"Our work included samples from a placebo-controlled trial of drugs against these parasitic worms. It suggests that the microbiomes of people who retained infection are somehow compromised to begin with. Something about their microbiomes makes them more prone to getting infected and to maintaining a chronic infection," Mitreva added.

The gut microbiomes of people who are able to clear the infections without drugs were more alike and differed markedly from the microbiomes of those who could not clear the infections without treatment.

As the study found characteristics of the microbiome that are discriminative of infection, this information could be used to predict who is most likely to develop severe and chronic infections and direct more preventive efforts to those individuals, the researcher said.

Currently, antihelminthic drugs are used to deworm people who are infected, especially school-age children and women of reproductive age.