There are, however, current examples of climate-related agent and/or vector incursions to territories or regions where they are newly endemic. Bluetongue virus, a disease agent among livestock, was unknown north of the Mediterranean until recently. Warmer winters allowed its traditional African/Asian vector, Culicoides imicola, to become endemic in southern Europe during the 1990s. The virus then began using indigenous European Culicoides species as vectors [18]. Another example is seen among oysters, which play a major economic role in coastal North Carolina. Dermo, a devastating protozoal disease caused by Perkinsus marinus, became established among Chesapeake Bay oysters during the 1980s and 1990s, when drought yielded increased salinity, when there were long periods of warmth during the spring and fall, as well as warm winters—conditions GCC will exacerbate. As a result, area oyster beds are now 5% of their previous size [19]. As a third current example of climaterelated disease effects, the incidence of human disease due to tickborne pathogens has increased as the burden of tick vectors increased in the wake of GCC. Workers from Sweden have shown that a 20-year increase in the incidence of tickborne encephalitis among humans is significantly related to changes in the tick-vector burden during milder winters and earlier arrivals of spring [20]. It is therefore important for decision makers to realize that climate is one factor—sometimes a determining factor—in whether a disease agent or vector expands or contracts its territory of endemicity.