The anti-EHEC O157:H7 IgM assay is a serological assay for standardized detection of antibodies against Enterohemorrhagic Escherichia coli (EHEC) O157:H7 LPS.EHEC (or Shiga-toxin producing Escherichia coli; STEC), serotype O157:H7, is recognized worldwide as a dangerous bacterial pathogen responsible for foodborne infections in humans.EHEC contamination occurs through the ingestion of contaminated food or water, person-to-person transmission, or contact with ruminants or their contaminated environment. The main symptoms are abdominal cramps and diarrhea, which is bloody in about 60% of patients and occurs after a median incubation period of three days. About 5–10% of people diagnosed with STEC O157 infection develop a life-threatening complication known as hemolytic uremic syndrome (STEC-HUS). This disease is defined by mechanical hemolytic anemia, thrombocytopenia, and acute renal injury and may lead to renal failure. EHEC infections are detected by an examination of fecal material, mostly through simultaneous testing of stool culture, shiga toxins immunoassays, and/or polymerase chain reaction PCR assays for the detection of shiga toxin (Stx) genes. However, the presence of EHEC in the intestines declines rapidly during the first 7 days of illness, whereas the average time between the first day of diarrhea and the development of HUS is approximately 5-13 days. As a result, examination of stool samples and/or PCR are only able to detect EHEC O157 infections for a short period of time after disease onset. In contrast, serum IgM antibodies to lipopolysaccharide (LPS) of EHEC O157:H7 can be detected from 5 days up to 2 months after onset of the symtoms. The anti-EHEC O157:H7 IgM assay (cat# HK508) is a robust serological assay for standardized detection of these IgM antibodies against EHEC O157:H7 LPS and can be used as an additional method improving the detection of EHEC infections.