Infectious diseases of the dog and cat

1
Infectious diseases of the dog and cat
2
The Respiratory tract

• Canine Distemper
• Canine Adenovirus type 2
• Parainfluenza virus 2
• Canine Herpesvirus 1

3
Distemper

• Paramyxovirus
• Disease of Canidae, seals, dolphins
• Serologically unique
• Virus strains differ in virulence
• Not very resistant

4
Patogenesis
Distemper

• Respiratory infection - aerosol
• Primary replication in macrophages of upper
  respiratory tract (within 24 hours) and
  subsequently in macrophages and lymphocytes
  (lymph nodes, tonziles)
• 6 days following infection, first wave of fever
  and lymphopenia
• Critical period 8-10 days p.i.
• Virus dissemination in epithelial cells and CNS

5
Critical period
Distemper

• absence of Ab
• Till 10 18 days
• Infection of epithelial cells
• Secondary replication
• 2nd wave of fever
• Lymphopenia
• Clinical signs

• Ab titre gt 100
• Virus elimination
• End of viremia
• Long lasting immunity

6
Distemper forms
Distemper

• Systemic Distemper
• Gastroenteritis
• Conjunctivitis
• Bronchitis, pneumonia
• Nervous form
• Hematogenous spread of the virus
• Demyelinisation
• Old dog encephalitis
• Hyperkeratosis (hard pad)
• Transplacental transmission
• Immunosupression, secondary infections

7
Diagnostics
Distemper

• Conjunctival swab
• pharyngeal swab
• urine, blood, serum
• Cerebrospinal fluid
• Postmortem lungs, tonzils, lymph nodes, urinary
  bladder, brain

8
Diagnostics
Distemper

• IFA - yes
• Isolation on tissue cultures no
• Isolation on embryonnated eggs no
• Intracytoplasmatic and intranuclear inclusions
  (in epithel. cells, neuronal cells, leukocytes)

9
Failure of IFA
Distemper

• Virus masking by antibodies
• Virus occurrence in focuses
• Time limited occurrence

10
Detection of Antibodies
Distemper

• VNT (paired samples)
• Indirect IFA
• Immune status
• (after 2nd. viremia)
• Prognosis non favourable lt 120
• Protection gt 1100
• Protection incertain 120 1100

11
Analysis of cerebrospinal fluid
Distemper

• Used to confirm CDV encephalopathy
• Detection of specific IgM and IgG in the
  CSF-acute Distemper

12
Kennel cough

• Viruses
• Parainfluenza virus 2
• Adenovirus type 2

• Replication in the lower part of the respiratory
  tract

13
Bacterial and fungal infections in the
respiratory system (RS)

• Nasal infections (acute/ chronic diseases,
  mycoses)
• Upper RT (kennel cough)
• Lower RT

14
Diagnosis of RS infections

• Localizing diseases
• Imaginig the RT (endoscopy, tomography, magnetic
  resonance imaginig)
• Obtaining material for microbiological
  examinations
• Swabing of RS
• Washing (nasal, transtracheal aspiration,
  endotracheal w., bronchoalveolar lavage)

15
The upper RS

•  
•  
• B.bronchiseptica prim. doxycycline
  p.o.
•  
• S.intermedius co-amoxicillin
  p.o.
• cephalosporins 1.g.
  p.o.
•  
• Escherichia coli flumequin
  p.o.
•  
• Pasteurella multocida cephalosporins 1.g.
  p.o.
• amox./ampicillin
  p.o.
•  
• Klebsiella pneumoniae flumequin
  p.o.
• Aspergillus spp.
•  

16
The lower RS Bronchopneumonia I.

• B.bronchiseptica prim. doxycycline
  p.o.
•  
• S.intermedius co-amoxicillin
  p.o.
• cephalosporins 1.g.
  p.o.
•  
• Escherichia coli flumequin
  p.o.
•  
• Pasteurella multocida cephalosporins 1.g.
  p.o.
• amox./ampicillin
  p.o.
•  
• Klebsiella pneumoniae flumequin
  p.o.

17
Bronchopneumonia II.

•  
•  
• P.aeruginosa enro/difloxacin
  s.c.,p.o.
•  
• Pseudomonas spp. amikacin
  i.v.,i.m.,s.c.
• piperacilllin/tikarcillin
  i.v.,i.m.
• gentamicin
  i.v.,i.m.,s.c.
•  
• Obligate anaerobes co-amoxicillin
  i.m.,s.c.,p.o.
• clindamycin
  i.m.,s.c.,p.o.
• Streptococcus spp. amox./ampicillin
  i.v.,i.m.,s.c.,p.o.
• benzylpenicillin
  s.c.,i.m.
• Mycobacterium spp.

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Pyothorax/pleuritis

•  
• Escherichia coli enro/difloxacin
  s.c.,p.o.
• Klebsiella pneumoniae enro/difloxacin
  s.c.,p.o.
•  
• Enterobacter spp. cephalosporins 2.-3.g.
  i.v.,i.m.,s.c.,p.o.
• P.multocida co-amoxicillin
  i.m.,s.c.,p.o.
• cephalosporins 1.g.
  i.v.,i.m.,s.c.,p.o.
• Obligate anaerobes co-amoxicillin
  i.m.,s.c.,p.o.
• klindamycin
  i.m.,p.o.
• S.intermedius co-amoxicillin
  i.m.,s.c.,p.o.
• cephalosporins 1.g.
  i.v.,i.m.,s.c.,p.o.

19
Enteric tract - viruses

• Canine parvovirus CPV-2
• Canine coronavirus
• Distemper
• Canine Adenovirus type 1 (CAV-1)

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Parvovirosis

• Canine Parvovirus
• Hosts Canidae
• Originated by mutations from Feline panleukopenia
  virus
• Three antigennic types CPV-2a,b,c
• Very stable and resistant
• Disease of 6 8 weeks old puppies

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Pathogenesis
Parvo

• Oral infection
• Primary replication in the regional lymph-nodes
  and tonziles (1 2 days)
• Replication in enterocytes, myocardium
• Virus is disseminated by blood
• Virus could be isolated from all tissues
• Significant affinity to replicating cells
  (mitosis)!!
• Enteritis
• Myocarditis

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Transplacental infection
Parvo

• Acute myocarditis in 3 8 weeks
• Mortality 20 100

23
Pathogenesis
Parvo

• Virus replicates in non-mature enterocytes
• Transient lymphodepletion and neutropenia..
  bacterias (sepsis) and viruses.

24
Diagnosis
Parvo

• Hemmaglutination test (porcine erytrocytes)
• Virus isolation on A72, CRFK no!
• Rapid immunochromatographic tests

25
Serological tests
Parvo

• Hemmaglutination inhibition test
• titres gt80 are protective
• Colostral antibodies persist till 8 16 weeks of
  age
• 4 fold rise is significant

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Canine Coronavirus
Corona

• Mild infection, often asymptomatic
• 70 Ab positive dogs
• Age 1-3 months
• Incubation period 3-4 days
• Involvement of small intestine, replication in
  mature enterocytes on the apical surface of
  intestinal villi, virus shedding up to 2 weeks
• Watery yellow-green diarrhea

27
Diagnosis
Corona

• Serology -meaningless- low titre of systemic IgG
• Paired samples
• EM, FA, Cell cutures
• Inaktivated vaccine interference with colostral
  antibodies

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The alimentary tract infections

• The oral cavity, pharynx
• The stomach
• The intestine

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The alimentary tract

• stomatitis , periodontitis
•  
• Obligate anaerobes clindamycin
  p.o.
• co-amoxicillin
  p.o.,s.c.,i.m.
•  gastritis
•  Helicobacter spp. amoxicillin-metronidazole
  p.o.
• Acute enterokolitis
•  
• Salmonella spp. flumequin
  p.o.
• Y.enterocolitica potenc.sulfonaides
  p.o.
• amox./ampicillin
  p.o
•  
• Campylobacter spp. erythromycin
  p.o.
• C.perfringens .amox./ampicillin
  i.v.,i.m.,s.c.,p.o.
• E.coli (EHEC,EAEC) potenc.sulfonamides
  p.o.
• E.coli sultamicilin
  i.v.,i.m.
• (neonatal sepsis) cephalosporins 2.-3.g
  s.c.,i.v.,i.m.
•  
•  

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The urinary tract

•  
• Escherichia coli potenc.sulfonamides
  p.o.,i.m.
•  
• Proteus mirabilis. amox./ampicillin
  p.o.,i.m.,i.v.,s.c.
•  
• Proteus vulgaris potenc.sulfonamides
  p.o.,i.m.,s.c.
• S.intermedius co-amoxicillin
  p.o.
• cephalosporins 1.g.
  p.o.
• Klebsiella pneumoniae cephalosporins 1.-3.g.
  p.o.,i.m.,i.v.,s.c.
• Pseudomonas aeruginosa tetracycline
  p.o.
•  
• Enterococcus spp. amox./ampicillin
  p.o.
•  
• Streptococcus spp. amox./ampicillin
  p.o.
•  

31
Urogenital tract and viruses

• Canine Herpesvirus CHV-1
• Distemper
• Parvovirus

32
Canine Herpesvirus

• Opportunistic pathogen
• Period of increased sensitivity
• last 3 weeks of pregnancy
• 3 weeks after birth
• stress

33
Pathogenesis
CHV-1

• Infection
• transplacental
• during parturition oronasal infection
• Primary replication in oronasal region
• Infection of mononuclear cells
• Spread in organs and tissues
• Latency

34
Diagnosis
CHV-1

• PCR
• Isolation on tissue culture??? (primary canine
  fibroblasts) CPE within 48 hours
• Neutralization test
• paired samples

35
The skin (pyoderma)

•  
• S.intermedius cephalosporins 1.g.
  p.o.
• co-amoxicillin
  p.o.
• oxacillin
  p.o.
• Escherichia coli potenc.sulfonamides
  p.o.
• Proteus mirabilis cephalosporins 1.g.
  p.o.
• Pseudomonas spp. enro/difloxacin
  p.o.
• Streptococcus canis cephalosporins 1.g.
  p.o.
• Bacillus cereus co-amoxicillin
  p.o.

36
CNS - viruses

• Distemper
• Rabies

37
The cat
38
Enteric Infections

• Feline Panleukopenia
• Feline infectious peritonitis - FIP

39
Felina Panleukopenia

• Parvovirus
• Ag related with other parvoviruses
• Oronasal infection
• Newborn kittens systemic or CNS infection
• Later panleukopenia and enteritis

40
Feline Infectious Peritonitis (FIP)

• Coronavirus
• Susceptible hosts felidae
• Antigenniv relationship with other coronaviruses
  (TGEV, CCoV)
• FIP mutation of ubikvitous feline enteral
  coronavirus (FeCV)
• Both viruses differ by macrophage tropism

41
Pathogenesis
FIP

• Primary replication epithelium of tonziles
• Replication in enterocytes
• Infection of macrophages allows virus spread in
  the organism

42
Pathogenesis
FIP

• Antibodies enhance infection (Fc receptors allows
  entry into macrophages)
• Immunocomplex
• Cell mediated response is protective
• Effusive - wet form
• Non-effusive dry form (immunity is partially
  preserved)

43
Diagnosis
FIP

• FeCV complicates diagnosis
• Cross reactivity of antibodies
• FeCV IFA titre 25 3200
• FIP IFA titre 100 - 64000
• Titre gt3200 evidence of FIP infection
• Similarity of genomes complicates PCR diagnostics

44
FIV

• Retrovirus
• Host felidae
• Main route of infection bite

45
Pathogenesis
FIV

• Target cells
• monocytes / macrophages
• lymfocytes T , B
• astrocytes
• perzistent, life-long infection
• Provirus integration into host cell chromosome
• Expression of virus proteins is restricted
• antigennic drift

46
Pathogenesis
FIV

• Acute phase (several weeks)
• fever
• neutropenia
• asymptomatic phase (3 5 years)
• ARC (AIDS related complex)
• generalized lymphadenopathy
• chroni secundary infection of mouth and upper
  respiratory tract
• 5 - 10 infected animals
• tumors
• Involvement of CNS

47
Diagnosis
FIV

• Antibody detection
• ELISA
• IFA
• Rapid tests
• Serological latency- several weeks
• PCR in some laboratories

48
Feline leukosis virus (FeLV)

• Retrovirus
• Disease of stray animals (1 - 7 of population)
• Infection occurs in the first 5 years of life
  (age resistence)
• transmission salive (bite), urine, feces, in
  utero

49
Pathogenesis
FeLV

• 3 biotypes
• FeLV-A Immunosupression, oportunistic infection
• FeLV-B Viremia, immunosupression, neoplasia,
  lymphomas
• FeLV-C thymus atrophy, lymphodepletion
• permissive cells macrophages, lymphocytes,
  non-mature enterocytes
• Antibodies are able to eliminate infection

50
Pathogenesis
FeLV

• Primary replication in macrophages and B
  lymphocytes in tonziles
• Primary viremia (1-2 weeks), virus is associated
  with mononuclear cells
• Infected cells are in bone marrow, intestine,
  oesophagus, stomach, kidney, pancreas, urinary
  bladder
• Virus is spread by saliva, urine, tears, feces

51
FeLV

• Early phase
• 4 16 weeks following infection (persistent
  viremia or regression)
• latent phase - up to 3 years
• Terminal phase
• lymphoid tumors, anemia, immunodeficiency
  (secondary infection)
• 83 of cats die during 3,5 years

52
Diagnosis
FeLV

• p25 antigen detection in blood, saliva
• ELISA
• IFA
• Rapid immunochromatographic tests
• Antibody detection no!