Chalkbrood is a fungus. The last I checked there aren't any fungus's that are very skilled with a compass. :-D
It is related to several functions....humidity, hive health, and genetics. Prolonged high humidity (rain) can trigger an outbreak, stronger, more hygienic hives can eliminate it quickly. Occasionally there will be poor genetics/hygiene and a queen will need to be replaced, but under most circumstances the hive can clear it out on their own.