Closure of live bird markets leads to the spread of H7N9 influenza in China

Local animal and public health authorities implemented closure actions at different times, and intensive media reports on H7N9 in different provinces started at varying times. The closure of LBMs resulted in a dramatic drop in local broiler prices in places with outbreaks and an increase in live chickens being transported to other LBMs in neighboring areas without human cases from infected areas. The study analyzed the impact of LBM closure on the spread of H7N9 influenza during the first two waves of the epidemic, which occurred from March to May 2013 and October 2013 to March 2014. The researchers collected data on human cases, poultry positives, and market closures or policy announcements in six provinces: Anhui, Jiangsu, Shanghai, Zhejiang, Fujian, and Hunan. The data showed that the closure of LBMs led to an expansion of H7N9 infection to uninfected areas, suggesting that provincial authorities in inland provinces should be alert to the risks of sudden changes in movement patterns for live birds after LBM closure or increased publicity about LBM closure. The study found that the closure of LBMs in early waves of H7N9 influenza resulted in the clustering of human infection in new areas in south eastern parts of China. The researchers used a timeline to describe LBM closures, relevant actions, changes in relevant media reports, prices, and volume of transported live poultry to cities in Hunan province. The analysis showed that the volume of transported live poultry to cities in Hunan province increased significantly after the closure of LBMs in neighboring areas. The study also analyzed the proportion of farmer patients among all patients in the first and second epidemic waves. The results showed that the proportion of farmer patients was significantly higher in the second epidemic wave compared to the first wave. The researchers used ArcGIS to create maps of human cases, poultry infection, LBM contamination, transportation direction for poultry, and human case clustering. The maps showed that the human cases were clustered in areas with high poultry density and LBM contamination. The study used SaTScan v9.3 to conduct clustering analysis for human cases and found that the human cases were clustered in areas with high poultry density and LBM contamination. The retrospective Space-Time analysis conducted by the researchers showed that the human cases were clustered in areas with high poultry density and LBM contamination, and the clustering was associated with the closure of LBMs in neighboring areas. The study's findings suggest that the closure of LBMs in early waves of H7N9 influenza resulted in the expansion of H7N9 infection to uninfected areas, and the clustering of human infection in new areas in south eastern parts of China. The researchers recommend that provincial authorities in inland provinces should be alert to the risks of sudden changes in movement patterns for live birds after LBM closure or increased publicity about LBM closure.