Epidemiology, Diagnosis, and Control of Canine Infectious Cyclic Thrombocytopenia and Granulocytic Anaplasmosis: Emerging Diseases of Veterinary and Public Health Significance

This review highlights the diagnostic methods used, the control strategies adopted, and the global epidemiological status of canine cyclic thrombocytopenia and granulocytic anaplasmosis at the animal–human interface. Canine anaplasmosis is an important worldwide disease, mainly caused by Anaplasma platys and A. phagocytophilum with zoonotic implications. A. platys chiefly infects platelets in canids, while A. phagocytophilum is the most common zoonotic pathogen infecting neutrophils of various vertebrate hosts. Diagnosis is based on the identification of clinical signs, the recognition of intracellular inclusions observed by microscopic observation of stained blood smear, and/or methods detecting antibodies or nucleic acids, although DNA sequencing is usually required to confirm the pathogenic strain. Serological cross-reactivity is the main problem in serodiagnosis. Prevalence varies from area to area depending on tick exposure. Tetracyclines are significant drugs for human and animal anaplasmosis. No universal vaccine is yet available that protects against diverse geographic strains. The control of canine anaplasmosis therefore relies on the detection of vectors/reservoirs, control of tick vectors, and prevention of iatrogenic/mechanical transmission. The control strategies for human anaplasmosis include reducing high-risk tick contact activities (such as gardening and hiking), careful blood transfusion, by passing immunosuppression, recognizing, and control of reservoirs/vectors.

Molecular Detection of Some Anaplasma Species in Blood of Dogs in Baghdad Province, Iraq

A total of 150 blood samples were collected from dogs and examined by the polymerase chain reaction (PCR) technique, which was used to detect the 16S RNA gene of Anaplasma platys and Anaplasma phagocytophilum. Subsequent analysis of the PCR amplicons was achieved by nucleotides sequencing of some positive samples. Totally, the findings show the presence of PCR products (i.e. Anaplasma spp. infection) in 12/150 (8.0%) of the dogs under study. While 5/150 (3.33%) of the cases were A. platys, 7/150 (4.66%) were A. phagocytophilum. Nucleotide sequencing confirmed the identity of the amplified genes whose sequences were compared with other references belong to 15 of 16S rRNA gene of A platys and 14 references of 16S rRNA gene of A. phagocytophilum, and the sequences of this study isolates were deposited on the Gene Bank. The identity and similarity scores between the isolates of this study and reference strains ranged from 98 to 99%. In conclusion, canine anaplasmosis prevalence in dogs could be underestimated in Iraq, and the phylogenetic tree of the local A. platys and A. phagocytophilum isolates were found to resemble other worldwide strains of Anaplasma spp. with a high degree of similarity.