Using a genetic technique rarely used to look at infections in human hosts, scientists from the University of Michigan studied how the E coli bacteria operate and discovered key differences between how the bacteria's genes behave in women and how they behave in mice used in experiments.
"If we want to prevent infections in humans, we need to look at what's going on with the bacteria while it's in humans," said Harry LT Mobley, the study's senior investigator.
Mobley's team found that specific surface structures of the E. coli found in mouse infections, which scientists consider a key to how the bugs thrive, were not prevalent in the human samples.
"That tells us it's more complicated than we thought and that there are some important differences we need to study in human infections," said Erin C. Hagan, one of the study's two first authors.
Last year, Mobley's team published a study that showed a vaccine they had developed prevented infection and produced key types of immunity in mice.
Even though researchers found differences in gene expression in the mouse and human samples, key targets of the vaccine related to iron acquisition were found in both samples, raising hopes that the vaccine would work in humans.
Still, he cautioned, developing and testing a vaccine for humans is several years away.
Gary J Faerber, of the University of Michigan Medical School said that urinary tract infections are an increasing concern and he has seen the number of infections that are resistant to common antibiotic treatments rapidly increase in recent years.
"That resistance is just going to keep going up," said Faerber. He described a recent, older patient whose infection would only respond to a single antibiotic costing 500 dollars per dose and which has to be administered intravenously.