Clinical observation of dogs serologically positive for the potentially zoonotic Ehrlichia Canis in the Philippines

Keywords: Ehrlichia canis, dogs, Philippines


Canine Ehrlichiosis is a disease with worldwide distribution caused by the potentially zoonotic Ehrlichia canis, a Gram negative intra-cellular pathogen transmitted by the Rhipicephalus sanguineus tick. Most studies have reported the epidemiological distribution of E. canis, but information on the clinical signs and hematological values were limited and retrospectively gathered. The present study endeavored to prospectively document the clinical profile of dogs that were serologically positive for E. canis in the Philippines. A total of 68 canine patients presented at the Makati Dog and Cat Hospital, Manila, Philippines were investigated. Inclusion criteria were history or presence of tick infestation, anemia, and/or thrombocytopenia. Blood samples were collected in EDTA tubes, and plasma samples were tested for E. canis using a commercial serological test kit. Clinical signs were recorded, and complete blood counts (CBC) were performed. Results revealed that 86.7% (59) were found serologically positive for E. canis. Most seropositive dogs had tick infestation, inappetence, and lethargy. Thrombocytopenia and anemia accompanied with normal WBC counts were the common hematologic findings. Statistical analyses revealed no significant differences in the hematological values of seropositive and seronegative dogs. Also, from the clinical signs, only lethargy was found to be significantly correlated with seropositivity (p value = 0.026). This study documents the clinical profile of dogs that were serologically positive for E. canis infection in the Philippines. Results are very useful to clinical practitioners who usually rely on clinical signs, CBC and commercial test kits for the diagnosis of Canine Ehrlichiosis

Author Biographies

Adrian P. Ybañez, University of the Philippines-Cebu

Adrian P. Ybañez, BAS, DVM, MBA, PhD, Dip. PCCP (Cand), Dip. PCVPH (Cand) is the Proffessor II, Department of Research and Laboratory Animal Facility, Gullas College of Medicine, Inc. and Research Consultant for the Laboratory Animal Research/Facility, University of San Carlos and University of Southern Philippines Foundation.

He is awarded as grand winner of the Outstanding Cebuano Youth Leader (TOCYL) – young professional category by the Cebu City government , Most Outstanding Veterinarian in the Veterinary Research Practice by the Veterinary Practitioners Association of the Philippines, the Outstanding Cebuano Awardee (Science and Technology Field) and Oustanding Young Professional in Veterinary Research by the Philippine Society of Animal Science.

Keith John V. Julian, College of Veterinary Medicine, Southwestern University

Keith John V. Julian, DVM is a Veterinarian DVM since 2016. Julian specializes in the area of Dog and Cat. He is particularly interested in the Clinical/Surgical and Technical/Laboratory procedures. He practice mainly at the Animal Care Hospital and Wellness Center in Mabalacat, Pampanga.

Sixto Miguel Alimudin S. Carlos, Makati Dog and Cat Hospital

Enrique Rodriguez Carlos, DVM took over the Dog and Cat Hospital in 1958, the same building in 185 Marquez de Comillas and later renamed 839 Romualdez Street. This was the first dog and cat hospital in Manila founded in 1927 by his father Sixto Almeda Carlos y Nepomuceno. The Carlos family have been offering services to dog and cat companion animals. Currently, Dr. Sixto Enrique Miguel Alimudin Carlos y Siapno continues the small animal practice in the Makati Dog and Cat Hospital.


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How to Cite
Ybañez, A. P., Julian, K. J. V., & Carlos, S. M. A. S. (2016). Clinical observation of dogs serologically positive for the potentially zoonotic Ehrlichia Canis in the Philippines. University of the Visayas - Journal of Research, 10(1), 1-6. Retrieved from