Babesiosis is the diseased state caused by the protozoal (single celled) parasites of the genus Babesia. Infection in a dog may occur by tick transmission, direct transmission via blood transfer from dog bites, blood transfusions, or transplacental transmission.

1. CANINE BABESIOSIS
Dr. Jibachha Sah
M.V.Sc, Lecturer, College of Veterinary Science,
NPI, Bhojad, Chitwan, Nepal
jibachhashah@gmil.com,00977-9845024121
Welcome to my lecturer notes

2. Introduction
.
●Canine babesiosis is a worldwide, tick-borne, protozoal hemoparasitic disease caused
by hemoprotozoan parasites of the genus Babesia(Taboda and Merchant1991).
●It is characterized by haemolyticanemia, thrombocytopenia, fever, and
splenomegaly.

3. ETIOLOGY :
●The two predominant species capable of naturally infecting dogs are Babesia (B.) canis and B.
gibsoni. Babesia gibsoni (formerly called "the Asian strain") that affects dogs in the mostly Asian
countries.
INCUBATION PERIOD : about two weeks.
Vector:
Babesia canis and Babesia gibsoni are the
two organisms commonly known to infect the
dogs are transmitted by ixodid tick vectors
(Sunitha et al., 2011).
Ixodid tick●Babesia species affecting dogs and/or cats are not reported to be
of zoonotic importance.

4. ●A tick carrying B. canis sporozoites attaches to a dog, and feeds on its blood, releasing many
sporozoites into the dog's bloodstream. Each sporozoite attaches to a red blood cell, and moves
inside the cell. This transmission requires 2-3 days.
Lifecycle

6. Pathogenesis
●Babesia spp. sporozoites are present in the salivary glands of the infected tick vector. They are
transmitted to the dog during feeding.
● This transmission requires 2-3 days. The sporozoites enter the red blood cells and multiply by binary
fission. Although dogs usually mount a good humoral immune response to infection, they are unable
to clear the parasitemia and become chronic carriers.
● The parasites induce FLP (fibrinogen like proteases) that cause the red blood cells to become sticky,
resulting in capillary sludging. Parasitized cells are sequestered in the spleen, and extravascular and
intavascular hemolysis occurs.
● The incubation period following tick transmission is 10-21 days.

7. Clinical sign
●Rise in body temperature (104.4ºF),
● Increased heart rate (122/min),
● Pale membranes,
● Dullness
● Peracute signs include acute onset of hypotensive shock, vasculitis, extensive tissue damage,
hypoxia, and death.
● Signs of acute disease include fever, lethargy, hemolytic anemia, thrombocytopenia,
splenomegaly, lymphadenopathy, icterus, and hemoglobinuria.
● Less common signs include ascites, peripheral edema, ulcerations, stomatitis, gastroenteritis, CNS
signs, acute renal failure, and rhabdomyolysis.
● Acute infections of virulent strains of Babesia canis have been associated with induction of the
systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS)
secondary to massive immunostimulation and cytokine release.
● Signs of MODS can include coagulopathies (DIC), adult respiratory distress syndrome (ARDS),
cerebral dysfunction, and acute renal failure.

9. Congested congenctival mucus membranes

11. ●Clinical signs are because of tissue hypoxia following anaemia and a concomitant systemic
inflammatory response syndrome caused by marked cytokine release [Lobetti RG.2006].

13. Yellowish discoloration of the abdomen
●In the severe form of the disease
(case-can observe marked haemolytic
anaemia, severe
acidbaseabnormalities with frequent
secondary multiple organ failure and
complications such as acute renal
failure(ARF), hepatopathy with
marked icterus, hypoglycaemia

17. Haemato-analyzer in Jibachha Veterinary hospital
Kathmandu
Haemato-analyzer in Jibachha Veterinary hospital
Chitwan

18. Ultra Sono Graphy(USG) of Babesia infected dog for diagnosis of spleenomegaly,
hepatomegaly at Jibachha Veterinary hospital, Kathmandu by Dr. Prabhakar K. Shah,
M.V.Sc ( Vet.Medicine)

19. Ulcerated skin lesions (A- Before treatment; B- After treatment).
Podo-dermatitis (A - Before treatment; B - After treatment).
Source:S. Sivajothi, B.and
Sudhakara Reddy Exploratory
Animal and Medical Research,
Vol.7, Issue 2, December, 2017
MANAGEMENT OF
DERMATOLOGICAL LESIONS
ASSOCIATED WITH BABESIA
GIBSONI IN DOGS

21. Biochemistry analyzer in Jibachha Veterinary
hospital Chitwan/kathmandu

22. ● Increased urinary methemoglobinemia levels, as a result of hemoglobin oxidation followed by
hemolysis, have been found in dogs with naturally occurring B. canis infections.
●Hypotensive shock results from the release and production of vasoactive amines and cytokines
which produce vasodilation.
●Hemolysis may involve proteases produced by the invading parasite, an immune reaction to
parasitized cells, and/or oxidative damage to erythrocytes.
Clinico-pathology
●The reason for thrombocytopenia in babesiosis could be due to platelet sequestration in the spleen
or immune mediated platelet destruction and development of disseminated intravascular
coagulation(A. L. Boozer and D. K. Macintire,2003)

23. ●Babesia initiates a mechanism of antibody-mediated cytotoxic destruction of circulating erythrocytes.
●Auto-antibodies are directed against components of the membranes of infected and uninfected
erythrocytes. This causes intravascular and extravascular haemolysis, which leads to anaemia.
●The blood picture showed anaemic changes like anisocytosis, poikilocytosis, polychromasia, nucleated
RBCS and neutrophilic leucocytosis with left shift due to marked systemic inflammatory response.
●Chronic hepatic insufficiency in case of babesiosis could lead to hypoalbuminaemia

24. Diagnosis

25. Babesia gibsoni species specific PCR assay.
Lane M: GeneRuler 100 bp Ladder; lane 1:
positive sample; lane 2: negative sample
control; lane 3: negative DNA
control.(Source:Suresh Gonde et al.,2014).
PCR (polymerase chain reaction) test
The PCR products were runon1.5%agarose gel and
stained with ethidium bromide.The size of the
amplified PCR product was 671 bp

26. ●The adverse effects of this medication include pain during injection and cholinergic effects such as
salivation, drooling, nasal drip or vomiting which can be mitigated by premedicating with atropine at
0.05 mg/kg.
● Additionally some less frequent adverse effects are panting, restlessness, diarrhoea, renal tubular or
hepatic necrosis and injection site inflammation and more rarely ulceration, which usually heals within
days to weeks.
Treatment
1.Imidocarb dipropionate(Imicarb): It is an aromatic diamidine
and is recommended to be used as 6.6 mg/kg intramuscularly
(IM) or subcutaneously (SC) with a repeated dose in 2 weeks
in dogs.(McHardy N et a.,1986).
Mechanism of action of imidocrab is interference with the
production and/or utilization of polyamines, or prevention of
entry of inositol into the erythrocyte containing the parasite.
The mechanism of Imidocarb includes nucleic acid damage
and inhibition of cellular repair and replication (Checa R, et
al.,20170

27. 2.Diminazene aceturate: It is 4,4′-(diazoamino) dibenzamidine diaceturate
which is widely used in tropical countries as a first-line agent for the treatment
of Babesia gibsoni infection of dogs, usually as an intramuscular injection of
3.5 mg/kg.
●Although diminazene aceturate has anti-Babesia activity, it often fails to
eliminate B. gibsoni from affected dogs and a relapse may occur.
intramuscularly,
●Mechanism o action of Diaminazine aceturate is acts by blocking the
replication of DNA of the parasite (Bhatt et al., 2005 and Bipin Kumar et al., 2008).
●Clinical signs associated with diminazene toxicity are depression or stupor,
continuous vocalisation, ataxia, opisthotonos, extensor rigidity, nystagmus and
seizures [Boozer AL et al.,2003].
●There are reported toxicity such as acute CNS signs including ataxia,
nystagmus and occasional seizures in dogs administered with one
recommended intramuscular dose (3.5 mg/kg) of diminazene for treatment of
babesiosis [Han D, et al.,2014].

29. 3.Treatment with a combination therapy of Clindamycin(CLDM), @ 25mg/kg PO q 12h,
Metronidazole(MNZ) @ 15mg/kg PO q 12h and Doxycycline(DOXY) @ 5mg/kg PO q 12h for
10days(Nandini MK et al.,2016)
4. Oral administration of a doxycycline–enrofloxacin–metronidazole combination (Lin and Huang 2010)
with injections of diminazene aceturate was found to be very effective in the management of
paraplegia in naturally occurring canine babesiosis caused by B. gibsoni.
5. A combination of atovaquone (13.5 mg/kg PO q 8 h with a fatty meal) and azithromycin (10 mg/kg PO
q 24 hours) for 10 days effective treatment.
6 Other drugs that may be effective against babesiosis include clindamycin and metronidazole.
Clindamycin has been used to treat B microti in people, and metronidazole (25-65 mg/kg q 24 h for 10
days) resulted in clinical improvement in one group of dogs with B gibsoni.
7. Uneventful recovery was recorded after treatment with intra muscular administration of two doses
of diminazene aceturate @ 7.0 mg/kg body weight and oral administration of clindamycin @ 25 mg/kg
body weight twice in a day. Three days of therapy and complete dermatological clinical cure
was obtained after two months of therapy.(S. Sivajothi, B. Sudhakara Reddy ,2017).

30. 8.Supportive treatment is advisable, particularly in valuable animals, and may include the use of anti-
inflammatory drugs, corticosteroids, and fluid therapy and blood transfusions may be life-saving in
very anemic animals.
In Babesia-infected dogs, intravenous fluid therapy is required for patients in shock, old dogs with
history of renal disease, clinically dehydrated patients and dogs with intravascular haemolysis and
haemoglobinuria.
Mildly dehydrated patients (approximately 5%) require 50 ml/kg body weight, and moderately
dehydrated (approximately 10%) requires 100 ml/kg body weight, whereas severely dehydrated (15%)
dogs require about 150 ml/kg body weight of replacement fluid.
Usually intravenous crystalloid fluid is indicated with correction of electrolyte and acid–base
abnormalities. It is important to maintain blood volume and adequate end-organ perfusion diuresis
and prevention of red blood cell sludging in capillaries [Ayoob AL et al.,2010].
Hetastarch (10 to 20 ml/kg) causes greater plasma volumes expansion, its beneficial in resuscitative
fluid therapy.

31. Whole blood/ RBC/plasma transfusion: Need for blood
transfusion depends on magnitude of anaemia (haematocrit
≤15%) and clinical signs such as dyspnoea or tachypnoea.
Initially blood is transfused slowly at 2 ml/ kg/h for the first
30–60 min while observing for transfusion reactions, such as a
sudden rise in body temperature and/or respiratory rate and
lip and ear pinna swelling.
Blood transfusion at Jibachha
Veterinary hospital,Kathmandu
Immunosuppressants: The use of immunosuppressant drugs
in dogs with immune-mediated haemolytic anaemia (IMHA)
or thrombocytopenia is controversial because these
conditions are always associated with infectious disease.
But in cases of unresponsiveness to antiprotozoal
treatment, the use of 2 mg/kg/day of prednisone is
recommended in infected dogs with moderateto-severe
clinical signs [Grundy SA, Barton C. 2001].

32. Control:
●Regular control of the tick vectors by routinely dipping or spraying pets or using tick collars or
spot-on preparations.
●Vaccines against other Babesia species such as B. gibsoni are currently being developed
including recombinant antigen and DNA vaccines [Fukumoto S et al.,2009]