Diseases from Rescue dogs Flashcards
where do rescue dogs come from within canada?
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
where do rescue dogs come from, from outside of canada? what issues do these present? what disease are our borders concerned with?
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
scope of dog international dog rescue issues
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
Recent Cases of Foreign Disease from Rescue Dogs
Canine influenza virus
Transmissible Venereal Tumour (TVT)
Brucella canis:
how does canine influenza spreas?
Spreads at shelters, dog competitions
origins of canine influenza
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
canine influenza zoonotic?
potentially
where does TVT come from? Prognosis?
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
where is brucella canis found?
Very common in Mexico, Central and South America
Also found in Asia, Africa and parts of Europe
foreign diseases with insect vectors
Leishmaniasis
Anaplasmosis
Ehrlichiosis
Babesiosis
Trypanosomiasis
nature of brucella canis organism
Small Gram-negative non-motile aerobic coccobacillus
disease caused by brucella canis
Reproductive disease most commonly, but also intervertebral disks, eye and kidney infections
Brucella spp. That Infect Dogs? zoonotic?
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
reproductive disease caused by brucella canis: what does it affect? symptoms and effects?
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
body systems other than repro affected by brucella canis
Most common after reproductive is discospondylitis
Uveitis
Meningoencephalitis
Lymphadenitis
General malaise
in what type of dogs in canada is brucella canis found? where is it not found?
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”
routes of infection for brucella canis
Oral, eye, vaginal, preputial – any mucous membrane
how is brucella canis spread among kennels
Among kennels – spread venereally- both from semen and
from vaginal (uterine) discharge
how is bricella canis spread within kennels?
Within kennel spread after abortion – vaginal discharge, abortuses and placentas contain billions of bacteria
pathogenesis of brucella canis
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)
classical signs of bricella canis in the female
Classically abortion in last trimester
Vaginal discharge for many weeks (compared to normal whelping lochia only 7 to 10 days)
classical signs of brucella canis in the male, and nature of shedding
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)
at what point post infection can we find antibodies of b. canis
Antibodies found by 3 to 8 weeks post-infection
a reasonable serological test for Brucella canis has these charactristics:
needs low false negative rate
has excellent sensitivity
usually means poor specificity
What is RSAT and its uses and limitations
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
common B. canis tests aside from RSAT
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)
what B. canis test should never be used for screening?
=DNA PCR
what is the use of AGID test for B. canis? limitations?
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
what can we culture to test for B. canis? what are limitations for these options?
Vaginal discharge good several weeks post-
abortion
Semen early in infection but later periodic shedding
Blood early in infection but very poor sensitivity later
confirmatory tests for B. canis?
Culture
DNA sequencing (NOT just a PCR test)
What do we do if we get a positive B. canis test?
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
what do we do if we find a positive case of B. canis in a kennel? what if there are livestock on the premesis?
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
tenets of B. canis management for a kennel?
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
Brucella canis treatment
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.
top breed affected by B. canis in Georgia
Golden retriever
state of B. canis in Ontario - where does it come from? where is it found?
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
where has B. canis been found in north america in the last decade?
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