Using a novel technique, scientists have completed a precise survey of how microbial communities in the human gut respond to antibiotic treatment.

They identified pervasive changes in the gut microbial communities of three healthy humans after a five-day course of the antibiotic Ciprofloxacin. Antibiotic treatment influenced the abundance of more than 1,000 varieties of bacteria.

Most of the bacterial community recovered and closely resembled its pre-treatment state within four weeks after the antibiotic course ended, but several bacterial taxa failed to recover within six months.

Changes in the composition of the gut microbiota can have important health effects.