That usually means two separate tests. But now scientists with the Agricultural Research Service of the United States Department of Agriculture report significant advances toward a single test that can detect both pathogenic E. coli O157:H7 and its toxins.
J. Mark Carter, leader of a research unit at the research service’s office in Albany, Calif., said the test, described last week at the annual meeting of the American Chemical Society, uses tiny polystyrene beads that are coated with antibodies for the proteins found on the bacteria and two of the major toxins it produces. The beads are mixed with a sample of ground beef that has been further chopped up in a blender, and then separated from the sample and analyzed.
Dr. Carter said that in addition to its two-in-one nature, the test is also quicker than current E. coli tests, with results in less than 24 hours rather than about a week. In addition to ground beef, he said, it could be used on lettuce and other vegetables. More work is required, but the plan is to have a commercialized test in a few years that could be used by governments and the food industry itself.