RESUMEN
Kala-azar was once transmitted in the northern area of the Yangtze River in China,including 16 provinces(cities or autonomous regions). Through the great continuing prevention and control effort,this disease has been effectively controlled in the most of endemic areas. However,because the epidemic factors of the disease are complex,this disease still transmits or sporadically occurs in the western part of China,including 60 counties of Xinjiang,Gansu,Sichuan,Inner Mongolia,Shanxi, and Shaanxi provinces(autonomous regions). Following the Management Measures for Health Criteria,the Diagnostic Criteria for Kala-azar(WS 258-2006)was compiled by the ex-Ministry of Health of the People's Republic of China and it was issued in April 7,2006 and implemented in December 1,2006. The Criteria consists of six parts,including the application range,terms and definitions,diagnostic principle,diagnostic standard,and differential diagnosis. Two informative appendices(epidemiolo-gy and differential diagnosis)and two normative appendices(immune-detection and etiological examination)are attached. The Criteria provides the technical reference for diagnosis of kala-azar in medical institutions and disease control institutions. Com-bined with the current epidemic situation of kala-azar in China,this paper interprets the main contents of the Diagnostic Criteria for Kala-azar(WS 258-2006),so as to promote its learning and implementing.