Late spring, summer and early fall produce a higher number of reported rabies cases. Does this mean that the warmer days are more conducive to the spread of the virus? Well, in a sense, yes. During these times of the year, animals, both wild and domestic, become more active. Humans are no different, as we tend to venture outdoors more often in the warmer months. Also, bats, which have the highest number of reported rabies cases, migrate to Michigan in the later summer and early fall. 

Rabies is caused by a virus that attacks the nervous system of warm-blooded animals. "Hydrophobia" is sometimes used when referring to rabies because it was once believed that animals having rabies were just simply afraid of water. The origin of the word "rabies" comes from the Latin term "rabere", meaning "to rage", as animals in the advanced stages of rabies often appear mad or insane and in a rage.