ABSTRACT
Over the past decade, syndromic surveillance, as supplementation of disease surveillance, has provided possibility of early alert in a real-time way for detection of emerging infectious diseases and outbreaks of widespread infectious diseases, resulting in improvement in sensitivity of outbreak detection and public health alert capacity. This tool has been highly valued and widely used in the world, and effective implementation has been observed in China. Upon abundant literature search, the authors reviewed the progress and advance of syndromic surveillance in early alert of emerging infectious diseases and outbreaks, and analyzed the problem met in the current situation in China when implementing syndromic surveillance in local facilities, which are high cost, lack of medical information platform, lack of real-time digital alert system and lack of a comprehensive information exchange platform. The authors suggested that syndromic surveillance should be implemented considering the local situation and performed in a more effective way in the current situation. Syndromic surveillance has to be integrated into the conventional public health surveillance systems and advanced laboratory networks. Digital information system is urgently needed to achieve real-time alert.
Subject(s)
Humans , China , Communicable Diseases, Emerging , Disease Outbreaks , Population SurveillanceABSTRACT
<p><b>OBJECTIVE</b>To understand the transmission mode of human infection with avian influenza A (H7N9) virus.</p><p><b>METHODS</b>Field epidemiological investigation was conducted for a family clustering of human infection with H7N9 virus in Hengxian county, Guangxi Zhuang Autonomous Region in February 2014. Two patients and their 82 close contacts were surveyed. The samples collected from the patients, environments and poultry were tested by using real time reverse transcriptase-polymerase chain reaction (rRT-PCR), and the samples from patients were used for virus isolation. The samples from 5 close contacts were tested with RT-PCR. The clinical data, exposure histories of the patients and the detection results of the isolates and their homology were analyzed.</p><p><b>RESULTS</b>Patient A became ill 4 days after her last exposure to poultry in Zhongshan, Guangdong province, and returned to her hometown in Hengxian 2 days after onset. Patient B was patient A's 5 years old son, who had no known exposure to poultry but slept with patient A for 4 days. He developed symptoms 4 days after last contact with his mother. Two strains of H7N9 virus were isolated from the two patients. The 2 isolates were highly homogenous (almost 100%) indicated by gene sequencing and phylogenetic tree. None of the other 81 close contacts developed symptoms of H7N9 virus infection.</p><p><b>CONCLUSION</b>Patients B was infected through close contact with patient A, indicating that avian H7N9 virus can spread from person to person, but the transmissibility is limited and non-sustainable.</p>