Predicting High Risk for Human Hantavirus Infections, Sweden

An increased risk for hemorrhagic fever with renal syndrome caused by Puumala hantavirus was forecast for Sweden in 2007. The forecast was based on a predicted increase in the number of Myodes glareolus rodents (reservoir hosts). Despite raised awareness and preparedness, the number of human cases during July 2007-June 2008 was 1,483, a new high.