Global Warming and Epidemic Trends of an Emerging Viral Disease in Western-Europe: The Nephropathia Epidemica Case

Abstract

Hantaviruses were first described in Korea in 1978, and are an important group of “new” pathogens, now constituting the most widely distributed zoonotic (i.e. transmitted from vertebrated animals to humans) viruses on earth. Hantaviruses are “emerging” viruses, and are now confirmed as being the only viral haemorrhagic fever agents with a worldwide distribution, including even the temperate Northern hemisphere (Clement et al. 2007a). They are spread by wild rodents (and perhaps also by insectivores), infecting man via their aerosolized but infectious excreta. So far, at least 23 different hantavirus species are officially recognized, each with its own main rodent reservoir, and hence specific geographical spread (Maes et al, 2009). The most important pathogens are Hantaan and Seoul virus in Asia, Puumala and Dobrava virus in Europe and West-Russia, and Sin Nombre and Andes virus in the Americas. American hantaviruses, discovered only in 1993, affect mainly the human lung and cause the “hantavirus cardiopulmonary syndrome” (HCPS), with a fatality rate of about 35%. By contrast, all Old World hantaviruses are targeted mainly to the human kidney resulting in the “haemorrhagic fever with renal syndrome” (HFRS), an often epidemic form of acute kidney injury (AKI), resulting in a rapidly progressive, but ultimately self-remitting acute renal failure (Clement et al., 2007a, 2007b). Among hantaviral pathogens, the European Puumala virus (PUUV) is the least severe. It causes an infection, aptly named “nephropathia epidemica” (NE), which in fact is a mild form of HFRS, with a very low fatality rate of 0.5-0.1 %. However, more severe cases do occur, resulting in multiorgan involvement, necessitating sometimes live-saving acute haemodialysis and/or mechanical lung ventilation in intensive care settings (Clement et al., 1994a, 2007a, 2007b).