US researchers are investigating a protein in a food-borne pathogen that could lead to the vaccine development in its common host, chickens. Scientists led by Qijing Zhangat Ohio State University have been awarded a three-year U.S. Department of Agriculture grant to study the major outer membrane protein of Campylobacter jejuni, a bacterium that harmlessly resides in birds and poultry. One negative aspect is that the pathogen can produce campylobacteriosis in humans, a gastrointestinal illness similar to Salmonella and E. coli. "Campylobacter is the No. 1 food-borne pathogen in the U.S. in terms of number of incidents each year," Zhang said. In addition to its high prevalence in birds, the pathogen has become increasingly resistant to antibiotics used to treat human illnesses, posing another challenge for controlling Campylobacter diseases. Several studies have estimated that 80 per cent to 100 percent of broiler chicken carcasses are contaminated with Campylobacter. Last year, OSU researchers discovered the Campylobacter gene encoding the major outer membrane protein, a protein that maintains the structural integrity of the pathogen and helps it adapt to the gut of its host. Currently, researchers are testing 150 Campylobacter strains.