In light of the ongoing severe outbreak of enterohaemorrhagic escherichia coli (EHEC) infection in Germany, the Taiwan Centers for Disease Control (Taiwan CDC) revises the case definition of EHEC infection to include EHEC O104:H4 infection in the list of Category II Notifiable Infectious Disease in order to reinforce surveillance of EHEC O104:H4 infection and implement relevant prevention measures.

The following case definition should be used to report confirmed cases of EHEC infection:
1. Clinical characteristics: Presence of gastrointestinal symptoms.In severe cases, bloody diarrhea, hemolytic uremic syndrome (HUS) or thrombotic thrombocytopenic purpura (TTP) may be present.

2. Laboratory characteristics: Detection of shiga-like toxin-producing E. coli isolated from the patient’s specimen (stool sample or anal swab).

3. Epidemiological characteristics (A case that has any one of the following characteristics.):
I. Patients who are close contacts of confirmed cases.
II. Patients who have been expose to the same source of infection as confirmed cases.

4. Case definition (A case that has any one of the following characteristics.):
I. Meeting the above-mentioned clinical characteristics.
II. Meeting the above-mentioned laboratory characteristics after being tested positive for the presence of shiga-like toxin-producing E. coli at a hospital.

The case definition of EHEC infection is revised to include EHEC infection caused by other shigal-like toxin-producing E. coli such as EHEC serotype O104:H4 in the list of Category II Notifiable Infectious Disease. Clinicians must report suspected cases that meet the aforementioned characteristics within 24 hours of diagnosis.Specimen from the cases must be collected and submitted to Taiwan CDC for final identification to facilitate prompt administration of treatment and prevent further transmission of the disease.