Guelph - A new sugar-based vaccine developed at the University of Guelph may eventually prevent "traveller's diarrhea" and other bacterial ailments.

New research shows that the new polysaccharide-conjugate vaccine, created by Guelph chemistry professor Mario Monteiro, protected mice and monkeys from infection by Campylobacter jejuni. The study was conducted with the United States Navy and appeared in the March 2009 issue of the journal Infection and Immunity.

C. jejuni is one of North America's leading bacterial causes of food-borne illness with up to about 50 cases per 100,000 people, and occurs at much higher rates in some developing countries, said Monteiro.

It causes "traveler's diarrhea," a common problem for Canadians visiting developing countries. The organism is also associated with irritable bowel syndrome and Guillain-Barré syndrome, a nervous system disorder.

Currently, there are no vaccines available for the organism.

"It's very rewarding to know you can make an impact in improving people's health with your chemistry," said Monteiro, who spent three days afflicted with traveller's diarrhea in Mexico four years ago.

This latest study new research clears the way for human trials, most likely in 2011. It may take up to 10 years for a vaccine to work through human trials.

This new conjugate vaccine contains sugars from two strains of C. jejuni. In tests by Monteiro's American collaborators, the vaccine proved 100-per-cent effective against diarrheal disease in monkeys.

Monteiro has worked on Campylobacter for almost two decades. He studies polysaccharides, or complex sugars, on bacterial surfaces. Unlike carbohydrates in foods, these sugars are antigens like the substances that define human blood groups.

Monteiro is one of the world's few researchers studying polysaccharide-based vaccines, working with graduate student Yu-Han Chen.

He also works with researchers in U of G's Ontario Veterinary College on carbohydrate-based vaccines for Clostridium difficile, a bug that has sickened and killed people in hospitals and nursing homes across Canada and has threatened various animal species. Other researchers have developed vaccines based on bacterial surface sugars for pneumococcal and meningococcal diseases.