Disease Burden Of Human Infections With H7N9 In Jiangsu Province

Background: Human infection with H7N9 has a high mortality rate and a large potential for pandemic,which has aroused worldwide concern.As of September 2017,human infection with H7N9 has caused five wave epidemics in China,of which Jiangsu is one of the earliest and largest affected provinces.However,due to the non-specificity of clinical symptoms,laboratory confirmed cases are only a small part of real cases.At the same time,the research on the life and economic loss caused by human infection with H7N9 is rare,which seriously limit our understanding of the severity of human infection H7N9 disease burden.Methods: Analyze the clinical and epidemiological characteristics of all laboratory-confirmed human cases of H7N9 infection which reported in Jiangsu province from 2013 to 2017.Use a probabilistic multiplier model to estimate the actual number of human cases of H7N9 infection.Calculate DALYs to assess the life loss of H7N9 cases.Investigate and calculate the direct economic burden of H7N9 cases.Use the human capital method to calculate the indirect economic burden of H7N9 cases.Results: The median age of H7N9 cases was 54 years and male accounted for 69.9% and there was no statistically significant difference between each wave of epidemics.The time from onset to diagnosis,ARDS,respiratory failure and death,and the rate of heart failure were significant different between each wave of epidemics.We estimated that,from 2013 to 2017,the actual number of H7N9 cases in Jiangsu Province was 2952,which was 11.8 times of the number of report cases.Estimated the actual incidence is 4/100,000.The actual life loss caused by H7N9(DALYs)is estimated to be 16548 years.The average life loss per year is 3677.50 years,and the average life loss per year per 100,000 people is 4.98 years(3.50 years after using the global population standardization).The total economic loss(including direct and indirect) was RMB 1.045 billion,with an average loss of RMB 232.14 million per year,with an average loss of RMB 353,868 per case.Conclusions: The clinical features of H7N9 cases are significantly different among different epidemic waves.The disease burden of human infection with H7N9 is significantly underestimated,and the average life span and economic loss of each case are enormous.If H7N9 cause a pandemic,it will cause extremely serious life expectancy and socio-economic losses.