Risk factors and potential preventive measures for nephropatia epidemica in Sweden 2011–2012: a case–control study

INTRODUCTION: Nephropatia epidemica (NE), a relatively mild form of hemorrhagic fever with renal syndrome caused by the Puumala virus (PUUV), is endemic in northern Sweden. We aim to study the risk factors associated with NE in this region. METHODS: We conducted a matched case–control study between June 2011 and July 2012. We compared confirmed NE cases with randomly selected controls, matched by age, sex, and place of infection or residence. We analyzed the association between NE and several occupational, environmental, and behavioral exposures using conditional logistic regression. RESULTS: We included in the final analysis 114 cases and 300 controls, forming 246 case–control pairs. Living in a house with an open space beneath, making house repairs, living less than 50 m from the forest, seeing rodents, and smoking were significantly associated with NE. CONCLUSION: Our results could orient public health policies targeting these risk factors and subsequently reduce the NE burden in the region.