Babesia microti: from Mice to Ticks to an Increasing Number of Highly Susceptible Humans

J Clin Microbiol. 2017 Oct;55(10):2903-2912. doi: 10.1128/JCM.00504-17. Epub 2017 Jul 26.


Babesia microti, a zoonotic intraerythrocytic parasite, is the primary etiological agent of human babesiosis in the United States. Human infections range from subclinical illness to severe disease resulting in death, with symptoms being related to host immune status. Despite advances in our understanding and management of B. microti, the incidence of infection in the United States has increased. Therefore, research focused on eradicating disease and optimizing clinical management is essential. Here we review this remarkable organism, with emphasis on the clinical, diagnostic, and therapeutic aspects of human disease.

Keywords: Babesia microti; United States; clinical significance; diagnosis; epidemiology; immunosuppression; infection; life cycle; prevention; relapse; transmission; treatment.

Publication types

  • Review

MeSH terms

  • Animals
  • Antiparasitic Agents / therapeutic use*
  • Babesia microti / immunology*
  • Babesiosis / diagnosis*
  • Babesiosis / drug therapy*
  • Babesiosis / epidemiology
  • Babesiosis / transmission
  • Hemolysis / physiology
  • Humans
  • Ixodes / parasitology
  • Mice
  • Tick-Borne Diseases / diagnosis
  • Tick-Borne Diseases / epidemiology*
  • Tick-Borne Diseases / parasitology
  • Tick-Borne Diseases / transmission*
  • United States / epidemiology


  • Antiparasitic Agents