Introduction

Classification

Taxonomy

• Phylum: proteobacteria.
• Class: alphaproteobacteria.
• Order: rickettsiales.
• Family: anaplasmataceae.
• Genus: anaplasma.

Etymology

• Gk.
  • An- without.
  • Plasma- anything formed or molded.
  • Literally: a thing (a bacterium) without form!
    • A phagocytophilum:
      • Phagein- to eat up, devour.
      • Phylum- friend, loving.
      • Literally: attractive to phagocytes.

Active Forms

Clinical Effects

Epidemiology

Habitat

• Distribution is associated with the bacterial species. Associated with ticks and possibly small rodents and deer.

Lifecycle

• Alternate infection of two distinct hosts, ticks and mammals. 
• In ticks, the bacteria resides in the salivary glands using upregulation selected tick salivary protein (SALP 16) to establish themselves. The bacteria persists through the nymphal molts but is not passed on transovarially. 

Transmission

Pathological effects

• Anaplasmataceae spp replicate in phagosomes.
• A. bovis targets monocytes, macrophages and granulocytes.
• A. marginale targets erythrocytes.
• A. phagocytophilum targets granulocytes and inhibits lysosomal fusion and delays apoptosis. Infection can result in protection against subsequent infections or in repeated bouts of bacteremia.

Control

Control via animal

• Appropriate tick control. 
• Minimize stressful events.

Control via chemotherapies

• A. phagocytophilum and A. marginale: lactating cows can be given Oxytetracycline Oxytetracycline. 

Control via environment

• Appropriate tick control.

Vaccination

• Vaccines are available for A. marginale.

Diagnosis

Further Reading

Publications

Refereed Papers

• Recent references from PubMed and VetMedResource.
• Brown W C & Barbet A F (2016) Persistent Infections and Immunity in Ruminants to Arthropod-Borne Bacteria in the Family Anaplasmataceae. Annu Rev Anim Biosci 4, 177-197 PubMed.
• (2016) Tickborne fever associated with abortion outbreak in dairy cows. Vet Rec 179 (8), 189-92.
• Atif F A (2015) Anaplasma marginale and Anaplasma phagocytophilum: Rickettsiales pathogens of veterinary and public health significance. Parasitol Res 114 (11), 3941-3957 PubMed.
• Aubry P & Geale D W (2011) A review of bovine anaplasmosis. Transbound Emerg Dis 58 (1), 1-30 PubMed.
• Woldehiwet Z (2006) Anaplasma phagocytophilum in ruminants in Europe. Ann N Y Acad Sci 1078, 446-60 PubMed.
• Kocan K M, De La Fuente J, Blouin E F & Garcia-Garcia J C (2002) Adaptations of the tick-borne pathogen, Anaplasma marginale, for survival in cattle and ticks. Exp Appl Acarol 28 (1-4), 9-25 PubMed.
• Savini G, Conte A, Semproni G & Scaramozzino P (1999) Tick-borne diseases in ruminants of Central and Southern Italy: epidemiology and case reports. Parassitologia 1, 95-100 PubMed.