Finally, identifying the specific point of contamination in a sprout outbreak is presently very difficult, due to the nature of sprout production. These patterns are repeated over and over again in our review of ten outbreaks and recalls linked to sprouts that have occurred since 1995. This year, that nightmare was repeated when a non-motile strain of E. coli O157 caused an outbreak in California. Outbreaks Contaminated irrigation water or contact with manure is not a concern for the vast majority of alfalfa seeds that are used in agricultural production. However, for the small proportion of seeds that are syphoned off for use for human food, such contamination is highly problematic.
Cattle feed lots located next to the alfalfa fields.
Water from the irrigation canals tested positive for generic E. coli and fecal coliforms, indicating possible contamination problems. Chicken manure was used to fertilize the fields. Horses were in field next to the seeds. Manure was stored next to the field. Because seeds are generally not intended for use as human food, seeds are frequently transported in open-weave sacks or other containers that don't prevent contamination after the farm.