There are two forms of ehrlichiosis in the United States; human monocytic ehrlichiosis and human granulocytic ehrlichiosis
Many patients with ehrlichiosis are admitted to the hospital for treatment
Monocytic ehrlichiosis is caused by Ehrlichia chaffeensis
Granulocytic ehrlichiosis is probably spread by the blacklegged tick Ixodes scapularis
The bacteria that causes granulocytic ehrlichiosis is not known, but suspected to be either Ehrlichia equi or Ehrlichia phagocytophila
Monocytic ehrlichiosis
Yes
Yes
Yes
Yes
Yes
About 100 cases of granulocytic ehrlichiosis have been reported in Connecticut, Massachusetts, Rhode Island, Minnesota, New York, and Wisconsin