Infectious Canine Hepatitis

1. INFECTIOUS CANINE
HEPATITIS
By:
Dr. Rashmi Singh, Assistant
Professor Veterinary Medicine
PGIVER, Jaipur

2. Brief Overview:
• Introduction
• Incidence and distribution
• Etiology
• Pathogenesis
• Clinical Findings
• Necropsy findings
• Differential diagnosis
• Treatment
• Prevention and Control

3. Synonyms:
• Rubarth’s disease
• Hepatitis contagiosa canis
• Contagious hepatitis
• Fox encephalitis

4. Introduction :
• An acute contagious viral disease of dogs.
• Irrespective of their ages .
• Characterized by severe depression, high rise of temperature, marked
leukopenia, vomition, diarrhoea, convulsion and prolong bleeding
time.

5. Distribution and Incidence :
• Rubarth first time recorded the disease in 1947 in Sweden.
• Disease is widely prevalent in many countries of the world.
• The disease is prevalent in epizootic proportions in India.
• Prior to the development of effective vaccines, seroprevalence of ICH
among dogs was 30-60% resulting in 10-30% mortality in dogs and
foxes.

6. Etiology :
• Is caused by a DNA virus.
• Which belongs to adenovirus group.
• There are two adeno viruses:
• Canine adeno virus -1-ICH
• Canine adeno virus-2 – causes respiratory disease.
• Virus can be preserved in 50% glycerine for several years.
• Virus can resist either, chloroform and alcohol.

7. Viral properties…
• Virus can be cultivated in the yolk sac of embryonated eggs.
• Can be grown in kidney cell culture of dog, ferret, racoon.

8. Susceptible host :
• All Canidae family is susceptible.
• Dog and foxes are the important species to suffer from this infection.
• In fox-the disease is manifested with neurological disturbances.
• Under one year age dog –show acute form of the disease.
• After which the dogs are inapparently infected with periodic relapses.
• Experimentally disease can be produced in pups and foxes.
• But not in ferret, coyote and other animals.

9. Mode of transmission :
• Most significant method - excretion of the virus through urine.
• Infectious canine hepatitis is not an airborne disease.
• Virus is present in the faeces, blood, saliva and urine of affected dogs.
• directly touching the snout or back end of infected/carrier, it can be
transmitted
• from contaminated feed or water bowl.
• Recovered dog shed virus through urine for about 6 months.

10. Pathogenesis:

11. Clinical features:
• Clinical features vary from a slight fever to death.
• The disease may flare up as:
• Acute form
• Per-acute
• Inapparent form

12. Acute form:
• Disease starts with apathy, anorexia and high rise of temp. upto 105
degree F.
• Vomition and diarrhoea.
• Faeces blood tinged , abdominal pain.
• First rise of body temp usually falls after 24 to 48 hours without
levelling to normal temperature.
• Rises again to form a saddle curve, which lasts for 6 days.
• Leukopaenia-2nd day of temp., persist 3-4 days.
• Buccal mucous membrane turn fiery red or haemorrhagic.

13. Cont….
• nose and mouth - reddened or covered with small bruises.
• Animal shows pain on palpation of xiphoid region.
• Dogs may show ‘tucked up’ condition of the abdomen.
• After 1-3 weeks following disappearance of clinical signs-a transient
corneal opacity may develop-this condition –hepatitis blue eye

14. Cont…
• Haemorragic spots may be seen over the skin of the abomen.
• Control of haemorrhage is difficult bcoz clotting mechanism of the
blood may be impaired.
• Prognosis is grave if the animal show profuse bleeding.
• Following 4-7 days many dogs may recover and their appetite return
to normal.

15. Cont…
• Fraser(1986) : corneal oedema and inflammation of the anterior uveal
tract -much specific manifestation.
• Wright et al.(1971): recorded signs of pneumonia in pups, with rapid
respiration, coughing, snapping and watery eye discharge. This may
be due to another strain of adenovirus infection.

16. Per-acute form:
• Animal die within 12-24 hours.
• Signs like febrile stage, leucopaenia, conjunctivitis, haemorrhages,
swollen tonsil, red buccal mucous membrane and tendered abdomen
can not be appreciated.
• The dog which is apparently normal in the night would die in the next
morning.

17. Inapparent form:
• Most common form.
• Dog shows a very mild or subclinical attack with a passing temp, mild
photophobia, enlarged tonsils and rapid recovery.
• The wt loss is slow .

18. Lesions:
• The liver is enlarged and friable on post-mortem examination.
• Extensive centrilobular necrosis leads to a pale, mottled appearance,
and widespread haemorrhage - on the serosal surface.
• Hepatitis leads to ascites and fibrinous or
Fibrino-haemorrhagic adhesions-b/w the lobes
of the liver.
• Large no. of intra nuclear inclusion bodies in
Hepatic cells & Kupffer cells.

19. Cont…
• Gall bladder- Enlarged, oedematous and thickened.
• Lymph glands- Swollen and haemorrhagic.
• Spleen- Enlarged, blood filled.
• Kidneys- Interstitial nephritis and cortical necrosis.
• Stomach & Intestine – Inflammed, paint brush haemorrhage of gastric
mucosa.
• Eyes-inflammation of iris and ciliary body.
-Inclusion bodies in the corneal cells and iridal endothelial cells.

20. Diagnosis:
• Clinical features.
• Joshua (1962): In hepatitis there is a thin thread pulse with weak,
rapid heart sounds. In tonsillitis or any general systemic infection, dog
always has bounding pulse and heart rate.
• Microscopic changes- intranuclear inclusion bodies in the liver, gall
bladder, brain and cornea.

21. Cont…
• Gel diffusion test- by this test diagnose the disease even when
decomposition of the animal has occurred.
• Compliment fixation test.
• Neutralization test.
• Animal inoculation test.
• Liver function test.

22. Differential diagnosis:
• Warfarin poisoning: Prolong clotting time,
Presence of source of poison, absence of intranuclear inclusion bodies,
absence of leukopaenia, absence of pain on palpation of liver.
Tonsilitis: caused by strepto or staphylococcus, coughing and nasal
discharge, difficulty in swallowing. It may be sec due to distemper or
hepatitis virus infection.

23. Cont…
• Leptospirosis : signs of jaundice and nephritis.
-Presence of leptospira in urin under dark field illumination.
-Fluorescent antibody test-rapid diagnosis by using specific
antisera labelled with a fluorescent dye.
• Distemper : Distinct clinical signs.
-Biphasic temp reaction ,signs of neural disorders. No change in
clotting time. absence of intranuclear inclusion bodies.

24. Treatment :
• No specific treatment.
• Symptomatic treatments are to be given.
• Antiserum may be useful.
• Severely affected case may require blood transfusion. Dose -5-8 ml/lb
of b.w. by slow iv infusion.
• Broad spectrum antibiotics –to control sec bacterial infection.
• Fluid and electrolytes are to be given.
• Protein hydrolysate –to restore vitality
• Careful nursing is of great importance.

25. Prevention and Control:
• Maternal antibodies dam to foetus in utero
• In new born pup by nursing the colostrums.
• Level of these antibodies declines to negligible concentration by 14-
16 wks.
• Immunization successful when maternal antibody titer declines below
1:100, which occurs at age 5-7 weeks of age.

26. Cont…
• Modified live CAV-1 vaccine are commercially available.
• Also give protection to CAV-2 infection .
• Modified live vaccines are widely used due to their high efficacy but
they induce post vaccinal ocular lesions including corneal opacity, and
virus excretion in urine in dogs post vaccination.
• Therefore CAV-2 vaccine evaluated.
• CAV-2 protects both against CAV-1 and CAV-2 infections.
• And no other adverse clinical signs and no urinary shading.

27. Cont…
• A bivalent vaccine containing modified canine distemper and CAV-2
or CAV-1 strain.
• Trivalent vaccine comprising of Bordetella bronchiseptica, canine para
influenza and CAV-1 .
• Polyvalent vaccine having live modified CAV-2, canine distemper
virus, canine parainfluenza virus and leptospira bacterin- is also safe
and provide good immunity.
• Another PV vaccine containing canine parvo virus, rabies, distemper,
CAV-1/CAV-2, canine parainfluenza, leptospira canicola and L.
icterohaemorrhagiae also provide 100% seroconversion with high
antibody titer. dose 1ml,route-I/V

28. Cont…
• Vaccination of dogs and the induction of active immunity have
controlled ICH in the canine population very effectively.
• Control measures in addition to vaccination are not necessary.
• Though the infected dog should be isolated from other healthy dogs.

29. Conclusion :
• Infectious canine hepatitis is a very contagious disease of dog
• That can cause inflammation of liver.
• It is not zoonotic but humans can be a source of its transmission if
carry virus on skin and cloths.
• It is also transmitted by contact with water and food bowls of
infected dogs (as by some other methods) so not allow your dog to
drink in communal water bowls.
• Treatment is symptomatic and it is almost always be prevented by
vaccination against the canine adenovirus.