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I recently received notification of 2 dogs which were brought into Alberta from the USA testing positive for "Anaplasma". Here is my reply to there question on how to deal with it.
Thank you for the update on what is going on with your dogs.
This is the first notification that I have of positive test cases of Anaplasmosis in
Anaplasmosis has been recognized as a disease in dogs, and appears in the literature in North America as far back as 1972.
Active cases can be expected in
Of course the main areas for Anaplasma and Babesia are in the tick areas of
Anaplasmosis is a disease causing significant signs of illness in dogs which include fever, anemia, thrombocytopenia (so petechiae, epistaxis, and melena), diarrhea, vomiting and lameness.
Besides a grossly abnormal CBC, there is usually significant liver involvement with elevation of liver enzymes and low protein levels (hypoalbuminemia).
There is not a recognized carrier state with Anaplasma. In other words the dogs will either be actively sick or are recovered, or were exposed and mounted an immune response to the disease.
The 4DX test is only testing for antibodies to anaplasma, therefore, provided the hounds are bright, alert, healthy and active, and show no abnormal blood work (CBC, platelets and liver enzymes), we are purely looking at post exposure or recovered dogs.
These positive testing dogs can be expected to remain positive for life.
For any cases where the dogs are symptomatic (sick), then blood smears can be examined to demonstrate parasites, and a PCR test can be done at the laboratory to demonstrate an active infection.
Treatment with Doxycycline is effective in curing this disease.
Any time that we do random testing we are going to show up asymptomatic seropositive cases.
We need to interpret these cases in the light of all the other factors associated with these patients.
So, if you are only dealing with a positive anaplasma antibody test, and providing everything else is normal, nothing further needs to, or should be done.
These dogs are not a risk to other dogs, and will not sero-convert (i.e. become ill with Anaplasma).
As far as being used as blood donors, I would look to use another dog wherever possible, just because exposure to ticks could mean that there are other undiagnosed infections present which might have a carrier state (Ehrlichia, Babesia or Lyme's Disease).
It is worthwhile to know that “Rocky Mountain Spotted Fever” (Rickettsia rickettsii) does not have a carrier state and so here too, positive healthy cases are only indicative of exposed or recovered dogs.
Should you require any further information on this or any other cases it is always my pleasure to help where I can.
Regards,
Dr Mark
Hi There Dr. Mark,
ReplyDeleteI stumbled upon your post as I have a 6 year old dog that tested +ve for anaplasmosis under the Indexx Snap 4DX plus test. She's from Manitoba where we do see significant occurrences of anaplasmosis in cattle from my understanding. She's active, alert and eating, and I'd say asymptomatic since she hasn't seemed off one day this year. That being said, she's a reserve dog from an area with significant tick populations and spends every summer in a highly wooded area with significant tick populations.
When I first saw the Snap test after it was inoculated and the 8 or 10 minutes waited, I saw only the positive control showing a blue dot. A vet tech told me she was clean and then I paid and left. 2 or so hours later we got a call back that she was positive for anaplasmosis.
Would this likely be considered a weak +ve? I'm wondering if these ELISA's need to be read within a certain amount of time to be accurate? Also, is there a confirmatory test available for anaplasmosis? I'd like to avoid treatment if unnecessary as she is healthy, and I'm certain the test originally illustrated only a +ve control. I'm also aware of a fair number of false +ves (and false -ve mind you) in human testing...
• If the test is positive, it may be a false positive, so the test can be repeated to see if it comes up positive again
ReplyDelete• If it retests positive the blood can be sent to the laboratory to look for active parasites with the PCR test
• the snap test test for antibodies rather than presence of protozoa, so really only shows that it has been exposed, built up an immunity and will remain positive for life.
• There is no reported carrier state so that this dog is not a risk for other dogs, nor will it relapse
• If there is active Anaplasma the dog will be SICK
• If it is sick it will respond to Doxycycline medication
• If it is not sick there is no point to do anything!!!
• Bottom line if the dog is fine I would ignore it, or at least retest it after 1 month and then re-evaluate.