Increased movements of people through travel and trade, social and environmental changes linked to urbanization
compounded with a rapid adaptation of microorganisms call for an effective global surveillance and response system as a communicable disease in one country today is the concern of all because Communicable Diseases recognize no borders in this new era whereby physical national borders become bridges to facilitate trade and travel. Epidemics of emerging
infectious diseases as exemplified by Severe Acute Respiratory Syndromes (SARS), Avian Influenza A/H5N1, Pandemic Influenza A/H1N1 have potential negative impact not only on human health but also on other socio-economic aspect.
In the 1969 version of the IHR, the three diseases that are required to be reported by States Parties to the World Health Organization, namely chorea, plague and yellow fever are no longer valid. The world requires an updated global system that can rapidly identify and contain public health emergencies and reduce panic and the disruption of trade, travel and society. The IHR 2005 requires World Health Organization (WHO) Member States to assess, develop, strengthen and maintain their country's capacity at a level to meet the minimum core capacity requirements for disease surveillance and response. The specific disease list is now replaced by a broader term of “Public Health Emergency of International Concern” (PHEIC).
Communicable Disease Surveillance and Response assists countries with building an integrated alert and response system for epidemics and other public health emergencies based on strong national public health systems and capacity and an effective international system for coordinated response.
In Cambodia, the Communicable Diseases Control (CDC)  Department was officially established as a result of the MoH reshuffle in 1997.   Its main function is to effectively prevent and control epidemic prone diseases through early detection and coordinated response system. In late 2003, a risk assessment and disease prioritization exercise was conducted. The list of four diseases in the weekly zero-reporting system was expanded to create a list of 12 diseases/syndromes. The reporting structures from the community to the national level were maintained in order to ensure that all diseases reporting are complete, accurate and timely. Download