Diseases from Rescue dogs

Question 1

where do rescue dogs come from within canada?

Answer 1

 Animal hoarders and other nefarious establishments shut down by
local authorities/humane society
 Northern communities and other impoverished communities where dogs are not considered to have an individual owner and little access to veterinary care exists

Question 2

where do rescue dogs come from, from outside of canada? what issues do these present? what disease are our borders concerned with?

Answer 2

 Countries with diseases not seen in Canada that have the potential to
spread widely in Canada since no protection in our population
Climate change making insect vectors move inland and north
 Currently our borders only deal with Rabies

Question 3

scope of dog international dog rescue issues

Answer 3

 In 2013/2014: 6189 imported dogs from at least 29 different countries into Canada via rescue groups – likely underestimated
 Rescue groups do not need to be registered
 Well-meaning people, but dangerous to our native dogs,
wildlife, and perhaps people
 Even from within Canada consider likelihood of no vaccination so common extremely communicable diseases like distemper or Brucella canis possible

Question 4

Recent Cases of Foreign Disease from Rescue Dogs

Answer 4

 Canine influenza virus
 Transmissible Venereal Tumour (TVT)
 Brucella canis:

Question 5

how does canine influenza spreas?

Answer 5

 Spreads at shelters, dog competitions

Question 6

origins of canine influenza

Answer 6

 Originally from equine influenza virus in Florida in early 2000’s (H3N8)
 Recently in Ontario from avian influenza origin from Asia (H3N2)
> Dogs rescued in Asia and came to USA and then to Canada
> Several outbreaks 2018 in Ontario

Question 7

canine influenza zoonotic?

Answer 7

potentially

Question 8

where does TVT come from? Prognosis?

Answer 8

 Several cases in Ontario from dogs from the Caribbean and Mexico
 Disease seen throughout the world - almost all stray dogs have it except for Northern and Western Europe, USA, Canada
 Highly contagious, sometimes fatal, expensive to treat

Question 9

where is brucella canis found?

Answer 9

 Very common in Mexico, Central and South America
 Also found in Asia, Africa and parts of Europe

Question 10

foreign diseases with insect vectors

Answer 10

 Leishmaniasis
 Anaplasmosis
 Ehrlichiosis
 Babesiosis
 Trypanosomiasis

Question 11

nature of brucella canis organism

Answer 11

 Small Gram-negative non-motile aerobic coccobacillus

Question 12

disease caused by brucella canis

Answer 12

Reproductive disease most commonly, but also intervertebral disks, eye and kidney infections

Question 13

Brucella spp. That Infect Dogs? zoonotic?

Answer 13

 Brucella canis
 Brucella melitensis
 Brucella abortus
 Brucella suis
 All zoonotic but B. canis only mild disease in people
 Brucella ovis not described in dogs or people

Question 14

reproductive disease caused by brucella canis: what does it affect? symptoms and effects?

Answer 14

 Testes, epididymis, prostate
 Uterus, mammary glands
 Initially males may have clinical orchitis/epididymitis/prostatitis/scrotal dermatitis, but eventually just firm irregular tissues and chronic disease
 Changes in sperm 2 to 4 weeks post infection
 Late abortion or apparent infertility

Question 15

body systems other than repro affected by brucella canis

Answer 15

 Most common after reproductive is discospondylitis
 Uveitis
 Meningoencephalitis
 Lymphadenitis
 General malaise

Question 16

in what type of dogs in canada is brucella canis found? where is it not found?

Answer 16

 For last 15 years, most cases of Brucella canis in Canada found in pets, not registered breeders’ animals
 Commonly discospondylitis in pets originating in “commercial kennels” in the States or from “rescued” dogs globally
 Rarely in purebreds from “non-commercial kennels”

Question 17

routes of infection for brucella canis

Answer 17

 Oral, eye, vaginal, preputial – any mucous membrane

Question 18

how is brucella canis spread among kennels

Answer 18

Among kennels – spread venereally- both from semen and
from vaginal (uterine) discharge

Question 19

how is bricella canis spread within kennels?

Answer 19

Within kennel spread after abortion – vaginal discharge, abortuses and placentas contain billions of bacteria

Question 20

pathogenesis of brucella canis

Answer 20

 Once infected, bacteria are phagocytosed by white blood cells and go to lymph nodes
 Replicate in lymph nodes (lymphadenopathy common) and may be maintained in spleen
 Bacteremia 7 to 30 days later
 This phase lasts 6 months to several years
 Attracted to reproductive tissues (steroid hormone dependent tissues)

Question 21

classical signs of bricella canis in the female

Answer 21

 Classically abortion in last trimester
 Vaginal discharge for many weeks (compared to normal whelping lochia only 7 to 10 days)

Question 22

classical signs of brucella canis in the male, and nature of shedding

Answer 22

 Initially sheds bacteria (urine and semen) for weeks to months  Then periodically sheds rest of his life (at least several years)
 Orchitis, epididymitis, sperm granulomas, scrotal dermatitis
 Abnormal sperm morphology, sperm agglutination (anti-sperm antibodies - break down in the blood testis barrier)

Question 23

at what point post infection can we find antibodies of b. canis

Answer 23

 Antibodies found by 3 to 8 weeks post-infection

Question 24

a reasonable serological test for Brucella canis has these charactristics:

Answer 24

needs low false negative rate
has excellent sensitivity
usually means poor specificity

Question 25

What is RSAT and its uses and limitations

Answer 25

Rapid Slide Agglutination Test (RSAT)

 Great screening test
 May be based on B.ovis antigen
 This results in MANY false positives
 Add 2-mercaptoethanol (2-ME) to precipitate non-specific IgM
>Usual cross-reacting problems: Pseudomonas aeruginosa, Bordetella bronchiseptica, mucoid Staphylococcus spp., Moraxella spp., other Gram- negatives

Question 26

common B. canis tests aside from RSAT

Answer 26

 Tube Agglutination Test (TAT)
 Immunofluorescent Antibody Test (IFA)
 Agar Gel Immunodiffusion Test (AGID)
Complement Fixation Test (CFT)
DNA polymerase chain reaction (DNA PCR)
Enzyme-linked Immunosorption Assay (ELISA)

Question 27

what B. canis test should never be used for screening?

Answer 27

=DNA PCR

Question 28

what is the use of AGID test for B. canis? limitations?

Answer 28

Agar Gel Immunodiffusion Test (AGID)
Used only AFTER a positive screening test
One with cell wall antigen (less specific)
One with cytoplasmic antigen (very specific)
Negative up to 8-12 weeks post-infection so poor screening test
Usually negatives should be repeated in a month

Question 29

what can we culture to test for B. canis? what are limitations for these options?

Answer 29

Vaginal discharge good several weeks post-
abortion
Semen early in infection but later periodic shedding
Blood early in infection but very poor sensitivity later

Question 30

confirmatory tests for B. canis?

Answer 30

 Culture
DNA sequencing (NOT just a PCR test)

Question 31

What do we do if we get a positive B. canis test?

Answer 31

 Unless the positive is by culture or AGID cytoplasmic antigen, all tests should be rerun
 Usually a month later to allow for further increase in antibodies in new infections

Question 32

what do we do if we find a positive case of B. canis in a kennel? what if there are livestock on the premesis?

Answer 32

 If any dog tests positive the whole kennel must be immediately be checked serologically
 Infected dogs must be euthanized OR immediately spayed/neutered, removed from kennel, placed on enrofloxacin (some say combo aminoglycoside and doxycycline) for 30 days and rechecked frequently – 30 to 90 day intervals – if rehoming is considered they should be screened for the rest of their lives and only after the screening test is negative
 Whole kennel must be retested every 30 days and positives removed and continue every 30 days until everyone is negative for two tests in a row

 Are there livestock on the premises?
Dogs can be infected by livestock Brucella spp., many are “reportable”
Canada Brucella abortus free since mid 80’s and never had B. melitensis or B. suis
 People should be tested, but be aware of false positive possibility

Question 33

tenets of B. canis management for a kennel?

Answer 33

 Prevention of infection is key
>Test all animals BEFORE coming into kennel
>With good screening test

Test all bitches to be bred to stud dog
Test popular stud dog at least twice annually
Investigate all abortions
Investigate all male infertility
Quarantine new dogs one month until two negative RSAT one month apart
Ship semen rather than bringing bitches in

Question 34

Brucella canis treatment

Answer 34

 Traditional belief that no antibiotic or combination works well
 Intracytoplasmic bacteria (macrophages)
 Enrofloxacin recently shown to not only cure, but restore fertility to infected bitches and dogs (one kennel of Poodles); some disagree
 In places where Brucella canis infection is reportable, infected animals are often euthanized
 Must Spay/neuter – so then only urine infected periodically
> males more of a problem than females
 Consider risks with children, elderly, immunocompromised, etc.

Question 35

top breed affected by B. canis in Georgia

Answer 35

Golden retriever

Question 36

state of B. canis in Ontario - where does it come from? where is it found?

Answer 36

 Last few years in Ontario (within a radius of 150 Km from OVC)
 1000’s of dogs tested and 100’s euthanized
 Most came to Canada from the USA - how many started
some where else?
 Most are not registered kennels – most in barns, sheds, lean to’s and never see daylight

Question 37

where has B. canis been found in north america in the last decade?

Answer 37

Infection diagnosed in many kennels in Georgia
and other southern states
From 2007 to 2010 saw 153 positive dogs from 9 kennels and 10 pets in Michigan – most came from other states including Kentucky, Ohio and Indiana
Rescued Chihuahuas from LA – one to Canada
Discospondylitis dog at OVC