GMS-CDC

Executive summary
A community-based surveillance system for avian influenza, influenza-like illness and dengue/dengue hemorrhagic fever was jointly developed by the Cambodia University of Health Sciences ; the National Centre for Parasitology, Entomology and Malaria Control ; the National Institute of Public Health; the Vietnam National Institute of Hygiene and Epidemiology; and Tay Nguyen Institute of Hygiene and Epidemiology.

Under the overall leadership of the University of Health Sciences, this joint-study was implemented in the border districts of Cambodia and Vietnam. The study was implemented on the Cambodian side from September to December 2009, coordinated by Prof. OUM Sophal; and from September 2009 to January 2010 on the Vietnamese side, coordinated by Dr. Le Thi Phuong Mai of the National Institute of Hygiene and Epidemiology. This system was developed by researchers from the universities and institutes of both countries, with technical and financial support from the Regional Coordination Unit of the Asian Development Bank Great Mekong Sub-region Communicable Disease Control Project.

This system was designed to provide syndromic surveillance for rapid and comprehensive detection of avian influenza and dengue fever/dengue hemorrhagic fever outbreaks in rural communities. In this system, Village Health Volunteers and other local private care providers were trained to identify and report the suspected cases and outbreaks in their communities to local health staff for confirmation and response. In Cambodia, phone calls were used by staff from each and every Commune Health Centre to collect data from village health volunteers on a weekly basis. In Vietnam, the forms developed for this project were used to collect and collate weekly data from the local community. In both countries, phone calls were used by volunteers for immediate reporting of suspected outbreaks to the Commune Health Centres and higher level. Monthly feedback meetings between volunteers and local staff were conducted systematically in Cambodia and to a lesser extent in Vietnam.

An evaluation conducted four to five months after implementation of the community-based surveillance system found that the system was able provide an effective complement the formal disease surveillance system in place, including the provision of missing information from the communities. Moreover, in Vietnam the sensitivity and specificity of case reporting by Village Health Volunteers were found to be high. Local community and local health staff acceptance and active participation in the novel system was high, as reflected by the regular and frequent household visits of made by volunteers to insure accurate and timely data collection and reporting. The visits were also designed to insure the continuing willingness of local staff to fully participate in data management, feedback and use.

The one problem encountered was the inability to assess the ability of the community-based surveillance system to capture avian influenza outbreaks. No cases of avian influenza were detected in the study areas. In addition, the implementation project was too short (only 4-5 months) to gather sufficient baseline data for dengue hemorrhagic fever to determine if an outbreak of this disease had occurred.

Nevertheless the study provided evidence that syndromic surveillance could be successfully applied in rural settings of developing countries to rapidly detect outbreaks by local community and staff. Countries need to develop a cost-effective and sustainable community-based surveillance system for outbreak detection and response that is adapted to their specific local context.

The study report can be downloaded here:  UHS - Scientific Report - Final (4.17 MB)