"' Human granulocytic anaplasmosis "'( "'HGA "') is a tick-borne, infectious disease caused by " Anaplasma phagocytophilum ", an obligate intracellular bacterium that is typically transmitted to humans by ticks of the " Ixodes ricinus " species complex, including " Ixodes scapularis " and " Ixodes pacificus " in North America.
