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A day in the life at Pathogenes

Between the dark and the daylight,

When the sun is ascending to power,

Comes a pause in the day's occupation

That is known as the Scientist's Hour.

It is dawn in tiny Fairfield, Florida, but Pathogenes is not sleeping in. Before daybreak, we begin to answer the emails which slithered in overnight when nobody was looking. It's also time to send out the documents which had gone directly to spam and to watch videos of ataxic horses from every state but Hawaii and Alaska, not to mention a few from our friends up North. We make early phone calls to our team of advisors across the country, wishing we had been more alert in Geography so that we'd recall that it is two hours earlier in the Mountain Time Zone. We are repaid for this failing later in the day when other poor Geography students telephone us at Pathogenes from Sacramento at ten p. m.

Our drop box at the end of the gated driveway oftentimes offers up samples from local vets and these are carried back to the lab. FedEx runs an early delivery route before the regular noon call so the gates must be opened well before eight a. m. The team arrives beginning at nine, a courier is dispatched to the small Farifield Post Office forthwith and the delivery trucks begin rolling in, culminating with UPS, the final visitor of the day, at seven p.m.

Our interpretations of the results from samples sent to us are the culmination of more than forty years of lab and field experience and fourteen years dedicated to EPM. And now we have yet another addition to the team. We call him Hal 9000P and he is tasked with test result interpretations and reporting.


Hal 9000’s people skills are renowned-- earning a top 100 award in his previous career, see his resume on Wikipedia. Hal 9000-P is a Cracker Jack at numbers, especially the numbers -1, 0 and 1. True/false and “not null” are Hal’s forte…beyond that Hal 9000 doesn’t read or speak. Austin trained Hal 9000-P to use our algorithm.

Submission Forms The submission form accompanies serum samples and gives us all the data we need to help you with your case of EPM. Our interpretation, coupled with a veterinarian’s neurological exam and field experience, simplifies treating equine protozoal myeloencephalitis. Sometimes, we find no submission form in the box, just a blood sample. Careful sleuthing by the lab crew can often reveal the source from the return address sticker. Failing that, we wait. Eventually, someone will call for the results.

Gait Assessment Score The veterinary exams are critical to a meaningful interpretation of our test. A trigger for “no interpretation” is absence of information on the submission form. A horse name and reporting email won’t give us anything to interpret—it may even trigger an email from Hal 9000.

It is well known that most horses in the United States are exposed to S. neurona resulting in serum antibodies, but yet there is no disease. This conundrum plagued EPM diagnosis for 25 years. We rely heavily on the gait assessment score (GAS), our hands are tied if there is no GAS on the form. A behavior problem should be scored as a “1”, issues such as head shaking and Horner’s (syndrome) make sense to us but Hal 9000 doesn’t interpret comments. He can evaluate a “1” listed as “Normal-deficit”, just check the box. We also need the submission form signed in order to use it for our FDA endeavors. You will get an interpretation without a signed submission, but the data is lost to our research. Be sure and download our newest, easy to fill out form on the services tab.

Send pre- and post treatment samples The follow-up sample is also critical to our analysis. If the second submission isn’t available, we won’t know how drugs. We hear that the once Grade 4 ataxic horse is now happily galloping in the meadow and can’t be caught…to us that is a treatment failure. We need that second signed submission form and blood sample.

Treatment response Initially our logic is based on the horse’s treatment history. If the horse has not been treated with an anti-protozoal AND there are antibodies to S. neurona then we want how the animal did clinically after treatment. Send us a quick email and let us know the response! Alternately, if there are no antibodies to S. neurona we still want your veterinarian to understand the disease process, this will lead to treatment options.

No S. neurona antibodies, GAS >0 We base our recommendations on statistics. We have tested and evaluated thousands of horses. We realize that some horses have no antibody; there are several situations could exist. No antibodies to S. neurona can indicate early infection (less than 17 days) or the horse has been exposed to anti-protozoals. Less likely reasons for lack of specific antibodies are that the animal has no ability to respond due to a defective immune system. This is a long held myth that there is a genetic predisposition to develop EPM—we don’t believe that. There is another theory…there are many unrecognized to S. neurona strains, thus all Sarcocystis may cause EPM—this is the Great Divide between our testing (specific) and the others (non-specific tests).

And, here is the most logical reason: it isn’t EPM. Yes, the horse can have neuroinflammation but not have active infection. In these cases we believe that a past infection with S. neurona, treatment of protozoa and not inflammation, is the problem. Our statistics show that in 80% of the cases without specific antibodies there is no infection. These cases can be treated. The numbers also indicate that 20% of the time we would miss early infections. When there is an early infection a post treatment test can determine active infection. A fourfold rise in titer (antibodies in the serum) indicates that there was active infection. The treatment decision is based on the veterinarian’s experience and risk assessment.

If a veterinarian is risk-averse, we offer C-reactive protein (CRP) testing. If the inflammation is due to ongoing S. neurona, Lyme, enteritis, gastritis, colitis, respiratory disease, tumor or other cause of inflammation the CRP will be high.

Treated The best time to retest is 8 weeks following treatment. We want to see that the antibodies are down to the undetected range. However, it the GAS is > 0 after treatment, we suggest determining the CRP and further treatment.

Relapse A relapse of EPM defined by us as insufficient treatment of IL6 mediated inflammation. Bute and banamine don’t work to treat this inflammatory path. A relapse can be due to incomplete removal of S. neurona, re-infection with S. neurona, or a reaction to another cause of IL6 mediated inflammation. We are documenting other reasons for IL6 inflammation, we recognize vaccination can induced ataxia in 0.3% of disease reported on our submission forms.

It’s the end of the day…we’ve used our lifetime of acquired knowledge to help you with your horse. We encourage you to forward your questions to Hal 9000…he’s waiting…

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