|Little Brown Bat with white-nose|
While the fungus kills off up to 90% of little brown bats in affected colonies, there had been no mass deaths in Europe where the fungus also occurs. It appeared that either the fungus evolved into a deadly variant in North America or it had co-evolved with European bats who had become immune and then migrated to our continent where the bats immune systems were defenseless.
"In the new study, the researchers infected little brown bats, a once-common species that the infection is wiping out, with isolates of either the North American or European fungus. Both types of infection either killed the bats or sickened them to a point where researchers had to euthanize them. This finding nixed the idea that the North American variety had mutated on its own to become more deadly."This means that somewhere in the great Columbian Exchange of the last 500+ years the fungus accidentally survived the trip across the Atlantic, accompanying humans or their cargo intact.
At least we have one piece of good news also reported today. Dr. Lynn Robbins of MSU reported that "No evidence of White Nose Syndrome has been found among bats at Sequiota Park Cave." The whole news release is available here.