In cases in which bone marrow aspirate and/or biopsy did not disclose mast cell involvement and that no other histologically organ involvement was proven, patients were considered to have CM. Public health surveillance for notifiable diseases has 2-O-beta-L-galactopyranosylorientin traditionally relied upon clinicians to spontaneously report new diagnoses of relevant conditions. Clinician-initiated reporting, however, is often incomplete and delayed. Electronic laboratory reporting Diethylcarbamazine citrate systems have improved both the volume and timeliness of reporting but these systems have important limitations: they cannot report purely clinical diagnoses, indicate when a result is likely a false positive, nor render diagnoses that require integration of laboratory tests along with patient clinical data and prior test results. The lack of specificity in electronic laboratory reporting increases workload for health departments compelled to investigate suggestive but non-specific lab results. In addition, electronic laboratory reporting systems do not report clinical data that can be crucial to guiding public health interventions such as patients�� pregnancy status, prescribed treatments, and full contact information. Electronic medical record systems are a promising new strategy to improve public health surveillance. These systems encode a wide array of clinical data including patient demographics, current and prior diagnoses, medication prescriptions, and laboratory results. These data might potentially be used to detect notifiable diseases that cannot be found by electronic laboratory reporting systems as well as to convey important information to public health authorities on patient demographics, clinical status, and prescribed treatments. Accurate identification of complex diagnoses from electronic medical records, however, requires the development of novel detection algorithms since diagnostic codes alone, such as International Classification of Diseases Ninth Revision codes, are imprecise. In order to assess the feasibility of public health surveillance for complex notifiable diseases using electronic medical record data, we sought to develop an algorithm to identify cases of acute hepatitis B using electronic medical record data.