Serology [31,32,33] or molecular methods targeting different genes, including 16S rRNA, 23S rRNA, and groEL, are more sensitive diagnostic tests for anaplasmosis in animals, as parasitemia can drop below the detectable limits of light microscopy [14,19,21,23,34,35,36]. This evidence concerns the gene HSPD1 and human granulocytic anaplasmosis.