(p. 442) Principles of outbreak investigation 

Outbreak investigation is an essential function of public health professionals. It is an opportunity to gain new knowledge of diseases and to discover the weaknesses of current public health practices and systems. Unfortunately, most of the outbreaks were left without investigation. This chapter will give the principle and important points about the outbreak investigation. The reader will know about the definition and how to detect outbreak from routine official surveillance and unofficial sources. The reader can assume oneself as investigator who has to organize the team, review previous knowledge, prepare the technical and management aspects, before starting the investigation. The reader will learn about the major ten steps in the investigation, with examples, which starts by confirming the existence of the outbreak, verifying the diagnosis, gathering case information, descriptive epidemiology, formulating and testing the hypothesis when necessary, conducting environmental surveys to supplement epidemiological evidence, and providing timely on-site reporting of the findings, with practical recommendations to local and national responsible authorities. The reader is reminded about the need to follow up on the recommendations and continue vigorous surveillance of the problem. The chapter end by forseeing more and more joint international investigations to control new emerging diseases and problems. After reading this chapter, one is convinced that outbreak investigation is an interesting, challenging task. Reader appreciate to be a competent investigator who combine sound scientific knowledge and good management skills together.