Ehrlichia chaffeensis is causative agent of ?

Ans. is 'a' i.e., HME Ehrlichiae These are gram negative, obligate intracellular bacteria which have affinity towards blood cells. They grow within phagosomes of phagocytes as mulberry-like clusters called morula. They are tick-borne. Three human infections caused by this group of organisms have been identified :? 1) Human monocytic ehrlichiosis (HME) - It is caused by E. chaffeensis, and transmitted by Amblyomma ticks. - Deer and rodents are believed to be reservoir hosts. - There is leucopenia, thrombocytopenia and elevated liver enzymes. 2) Human granulocytic ehrlichiosis (HGE) - It is caused by E. equi (E. phagocytophila), and transmitted by ixodes ticks. - Deer, cattle and sheep are suspected reservoirs. - There is leucopenia and thrombocytopenia. 3) Glandular like fever - It is caused by Ehrlichia sennetsu - No ahopod vector has been identified and infection is caused by ingestion of fish carrying infected flukes. - Theres is lymphoid hyperplasia with atypical lymphocytosis. Doxycycline is recommended for treatment of ehrlichiosis.