Zoonotic Brugia infection in western Michigan.

A case of zoonotic lymphatic filariasis is reported from a resident of Michigan. Numerous sections of a small, nongravid female worm, measuring approximately 65 microns in diameter, were identified in histological preparations of an excised inguinal lymph node. Based on its location, small size, thin cuticle, small number of muscle cells, and paired uterine tubes, the worm was identified as a Brugia species, undoubtedly of zoonotic origin from the local animal population. The pathological response of the host to the parasite was one of hyperplastic lymph nodes with a focal granulomatous reaction. This is the first such case to be reported from Michigan and further expands the geographical range of states in which zoonotic Brugia infection have been reported.