🦠microbiology review

Anaplasma phagocytophilum

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Anaplasma phagocytophilum is a gram-negative bacterium that infects white blood cells and is the causative agent of anaplasmosis. It is primarily transmitted to humans through tick bites.

5 Must Know Facts For Your Next Test

  1. Anaplasma phagocytophilum is most commonly transmitted by Ixodes ticks, including the deer tick.
  2. The bacterium targets neutrophils, a type of white blood cell, compromising the immune system.
  3. Symptoms of anaplasmosis include fever, headache, muscle pain, and sometimes severe complications like respiratory failure.
  4. Diagnosis is typically confirmed through serological tests or PCR (polymerase chain reaction).
  5. Treatment often involves antibiotics such as doxycycline.

Review Questions