Increasing incidence of hemorrhagic fever with renal syndrome could be associated with livestock husbandry in Changchun, northeastern China.

Jing Wu,Xin-Lou Li,Ya-Qin Yu,Jian Zhu,Dan-Dan Wang,Ying Zhang,Li Yan,Li-Qun Fang,Sake J De Vlas,Ya-Wen Liu,Bo Wang,Wu-Chun Cao

doi:10.1186/1471-2334-14-301

Abstract

BackgroundSince the end of the 1990s, the incidence of hemorrhagic fever with renal syndrome (HFRS) has been increasing dramatically in Changchun, northeastern China. However, it is unknown which, and how, underlying risk factors have been involved in the reemergence of the disease.MethodsData on HFRS cases at the county scale were collected from 1998 to 2012. Data on livestock husbandry including the numbers of large animals (cattle, horses, donkeys and mules), sheep, and deer, and on climatic and land cover variables were also collected. Epidemiological features, including the spatial, temporal and human patterns of disease were characterized. The potential factors related to spatial heterogeneity and temporal trends were analyzed using standard and time-series Poisson regression analysis, respectively.ResultsAnnual incidence varied among the 10 counties. Shuangyang County in southeastern Changchun had the highest number of cases (1,525 cases; 35.9% of all cases), but its population only accounted for 5.6% of the total population. Based on seasonal pattern in HFRS incidence, two epidemic phases were identified. One was a single epidemic peak at the end of each year from 1988 to 1997 and the other consisted of dual epidemic peaks at both the end and the beginning of each year from 1998 to the end of the study period. HFRS incidence was higher in males compared to females, and most of the HFRS cases occurred in peasant populations. The results of the Poisson regression analysis indicated that the spatial distribution and the increasing incidence of HFRS were significantly associated with livestock husbandry and climate factors, particularly with deer cultivation.ConclusionsOur results indicate that the re-emergence of HFRS in Changchun has been accompanied by changing seasonal patterns over the past 25 years. Integrated measures focusing on areas related to local livestock husbandry could be helpful for the prevention and control of HFRS.

Highlights

Since the end of the 1990s, the incidence of hemorrhagic fever with renal syndrome (HFRS) has been increasing dramatically in Changchun, northeastern China
A rapid increase in HFRS incidence occurred at the beginning of each year and a smaller increase in incidence occurred at the end of each year (Figure 2)
The results of this study indicated that prevention and control of HFRS in Changchun will benefit from targeting control measures at R. norvegicus populations, especially at livestock husbandry sites

Summary

Introduction

Since the end of the 1990s, the incidence of hemorrhagic fever with renal syndrome (HFRS) has been increasing dramatically in Changchun, northeastern China. It is unknown which, and how, underlying risk factors have been involved in the reemergence of the disease. Hemorrhagic fever with renal syndrome (HFRS) is one of the rodent-borne diseases caused by a hantavirus (family Bunyaviridae). HFRS mainly includes epidemic hemorrhagic fever (EHF), which mostly occurs in Asia, and nephropathis epidemica (NE), which mostly occurs compared to SEOV infection [1,9]. The HFRS incidence has increased significantly since the end of the 1990s, especially in Changchun, the capital of the province [14]. The objectives of our study were to explore the spatial and seasonal patterns of HFRS distribution for different epidemic phases, and to study the association between HFRS incidence and livestock husbandry, climate factors, and land cover

Objectives

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Results

Discussion

Conclusion