(WFRV) -- Salmonella hospitalizes thousands and kills hundreds every year.  But now, doctors are using it to fight cancer.

Doctor Edward Greeno is testing salmonella to fight cancer.

"We're trying to induce an immune response with the salmonella," said Doctor Edward Greeno.

Doctors tried this 150 years ago, but it often killed patients.

Today, researchers can alter salmonella to make it safe.

"I'm certainly quite hopeful that this going to turn into something that will come into regular clinical use as a valuable agent," Doctor Greeno said.

Salmonella naturally travels to the GI tract, so colon and liver cancers are good targets.

"The bacteria, interestingly, actually doesn't just grow inside your body," says Doctor Greeno.  "It actually gets inside the individual cells so that it's right there inside of the tumor cells."

Salmonella isn't the only bacteria under study.  Researchers elsewhere are testing Listeria to fight liver cancer.

Scientists at the University of Florida are studying bacteria in coral reef to fight cancer and bone disease.

"We really have the tools now to start manipulating bacteria and make them do the things that we want them to do," Doctor Greeno says.

The treatment is easy.  Patients simply drink a solution that contains salmonella,  and there are minimal side effects.