Hantavirus: an increasing problem?

Hantaviruses are enveloped RNA viruses and members of the Bunyaviridae family. They are transmitted from various rodent hosts by inhalation of infected urine, saliva or faeces. Infection in rodent hosts is inapparent but persists for life. Person-to-person spread of hantavirus has not been described. Two main presentations of the disease occur. Haemorrhagic fever with renal syndrome (HFRS) is due to Hantaan, Seoul, Puumala, Porogia and Belgrade viruses. In general HFRS due to Hantaan, Porogia and Belgrade viruses is more severe and has higher mortality than that due to Puumala (nephropathia epidemica) or Seoul viruses. Hantaan is predominant in the Far East (Korea, Japan, China), Porogia and Belgrade in the Balkans, and Puumala in Western Europe; Seoul has a world-wide distribution. Hantavirus pulmonary syndrome (HPS) is a recently described infection with high mortality (60%) due to adult respiratory distress syndrome. The virus (Muerto Canyon Virus) is a hantavirus but different genotypically from previous strains. Management of hantavirus infections may require bed-rest, sedation, circulatory and ventilatory support and renal dialysis. Ribavirin if administered early in the illness may be of benefit.