Like any wild animal that is found in Michigan, bats can be afflicted with a number of parasites. Bats can carry insects such as mites, fleas and bat bugs. These insects feed on all of the bat species found in Michigan, and are most frequently associated with bats that roost in colonies, such as the Big Brown Bat.
Bat bugs are a specific species of insect that is related to the bed bug that afflicts humans. They look almost identical to bed bugs and a microscope is required to differientiate the species. We suspect that many bed bug complaints are really misdiagnosed bat bug problems. Many pest companies are not looking (or trained) to identify bats in the attic space. If you are finding these bugs in the bathroom sink, or on the ceiling, then the source of the problem may be the attic! The bugs can make their way through bathroom vents or recessed lights to get inside the home. Often, a pest control technician has to look at the behavior to determine the species! Additionally, bats can go undetected in attic spaces for many years, and you may not be aware that there is a problem.
In general, bat bugs perfer bats as their primary host. However, they may feed on other animals, and will bite humans in the absence of their primary hosts.
In order to control bat bugs, the bat colony must be evicted from the home. Otherwise, the primary host is available as a food source for the bugs.