Multi-country comparative assessment of avian influenza (H5N1) human cases surveillance in Asian countries

Although different opinions exist if the H5N1 will be the next human pandemic strain, a future novel influenza pandemic is considered inevitable. Once the pandemic occurs, it will be a serious public health emergency without borders. Effective surveillance system, especially in countries with confirmed H5N1 human cases, is vital for early detection of the pandemic that may lead to either rapid containment or swifter mitigation measures of public health impacts such as preparation of pandemic vaccines. In purpose of aiding rational policy directions in strengthening the surveillance in Asian countries with necessary international assistances, a multi-country comparative assessment of the surveillance of H5N1 human cases was conducted. The study applied both reviews of published protocols, guidelines and policy documents, and key informant interviews on public health officials, both central and local, regarding surveillance implementations and responses to avian and human cases. Different aspects of the surveillance, namely definitions of reportable condition, reporting mechanisms, reporting sensitivities per population, specimens collection and shipment mechanisms, laboratory testing and responses to avian and human cases, were compared amongst Indonesia, Vietnam, Myanmar, Pakistan and Japan. Routine reporting of suspected cases from all health facilities was considered essential whereas community-based cluster reporting or active searches of human cases around poultry outbreaks alone did not ensure sufficient population-based reporting sensitivity and area coverage. Countries envisaged very diverse domestic laboratory network for sub-typing. One developing country even planned to install more than 30 laboratories nationwide that may potentially cause problems of quality control and biosafety. In response operations, major difference was observed whether to isolate close contacts in households or not. Above major findings indicate a large diversity in surveillance structures, implementations and performances across different countries. Knowledge sharing and mutual learning as well as multi-country stewardship are essential for optimizing the surveillance in each country.