Again with the rule: CO2 causes a "plethora of food" for "bad" animals, while it causes "good" animals to starve

Global Warming Linked To European Viral Epidemic

ScienceDaily (Jan. 16, 2009) — An epidemic of the viral disease nephropathia epidemica (NE) has been linked to increases in the vole population caused by hotter summers, milder winters and increased seedcrop production by broadleaf trees. New research links outbreaks of this rodent-borne disease to known effects of global warming.
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NE is caused by infection with Puumala virus (PUUV), which is spread by the bank vole, a rodent common throughout most of Europe. The authors believe that warmer weather causes increases in the amount of 'mast', plant seeds from oak and beech trees, that forms the voles' staple diet. This plethora of food results in increases in the vole population and warm summers raise the chances that people will visit the forests where the voles live. According to Clement, "Since 1993, each NE peak has been preceded by increased autumnal mast formation the year before, resulting in yearly NE numbers significantly higher than those during the mast years themselves".