Has anyone successfully battled Strep Zoo? Please check in!

[sascha]

I’ve been battling what we believe to be recurrent strep zoo infections (first infection we did the deep swab and culture and more recently did a BAL which also showed strep z - yes, I know it’s ubiquitous, but nothing else of note has been cultured) in my horse for the past year. Going 4 months in a row without a round or three of antibiotics is a stretch

Looking for any anecdotal (or research! - apparently there’s not much out there, or my usually excellent Googling skills suck on this subject) from folks that have had a similar experience and have found a way through to the other side and back to not having to treat recurrent infections every couple/three months or so.

If you were successful, how long did you treat? How did you figure out when to finally stop treating? What drug/s did you use?

Thanks in advance for ANY scraps of information you may provide me.

One more bit of weirdness to add in case it helps, knock on wood, no other horse in her barn/turnout group has become ill so if it is indeed strep zoo causing these stupid infections, it’s not a particularly virulent strain. Maybe? I don’t know, we are all guessing at this point!

Signed,

More Grey Hairs Today

[mbv]

What part of your horse seems to be infected with Strep zoo? Sounds like respiratory but a deep swab (pharyngeal??) does not represent what is happening in the lungs very well. Even a BAL is not the ideal lung sample for culture. Has your horse been checked for inflammatory airway disease? It can be associated with Strep zoo. More information may allow others to help - Strep zoo can cause infections throughout the body so more context is needed.

[sascha]

She has mild IAD but with no (as yet) discernible lung sounds.

Parts that are affected seem to be restricted to upper airway.

She’s had masses of standing scopes including into the guttural pouches, a couple of BALs, dynamic scope, large set of head rads, and I can’t remember what else. The list is long diagnostics (originally for noisy breathing) have been split between excellent teaching hospital and on farm with several different vets.

In terms of fixing stuff - none of the usual lung meds/inhalers have helped.

What has helped, but only for a couple to four months at a time has been ceftiofur and/or SMZs. She becomes a new horse at the end of a treatment or double or triple course as for her first and second infections. Noisy breathing hugely reduced, exercise intolerance practically erased, and respiratory rate almost that of a healthy horse.

If there is anything else I haven’t answered, let me know and I’ll do my best!

[Equisis]

I’m guessing ceftiofur and SMZs were used based on the results of a sensitivity? Have you tried nebulizing with ceftiofur? We had a horse with what we believed to be a chronic respiratory infection that seemed to come and go, cultures sometimes grew strep z. and an occasional fungal something but always cleared up, only to come back. Lungs sounded clear but when we finally ultrasounded the lungs, we saw some infection. Two months on nebulized ceftiofur (I think we added rifampin as well) and touch wood, it’s been clear since.

[No1]

Have her guttural pouches actually been flushed?

[sascha]

No. Not flushed. Looked at with a scope and radiographed but not flushed.

[sascha]

Brilliant! This is exactly the sort of anecdotal evidence I’m looking for! Thank you!

And yes, SMZs and ceftiofur were our immediate go to (she was very sick the first time a year ago so we threw the pharmacy at her) and both drugs were confirmed as the right ones to be using.

[sascha]

Also, no to nebulized ceftiofur. Hadn’t even heard of that! I will check it out. I’ve always used injectable.

[sascha]

Conjuring @Ghazzu for a check in? If you have a moment, it would be much appreciated! TIA.

[Ghazzu]

Sounds like you have been handling this in a reasonable fashion.
Also sounds like you have done antimicrobial sensitivity testing on the isolate?

The idea of checking the guttural pouches for a bacterial hideout in’t a bad one.

What has been the duration of the treatment with antibiotics? I’d guess you tried a relatively lengthy course of treatment after the initial go-round?

I’ll poke around in the literature and see what I can find, but the vet school would likely be pretty up to date on the latest and greatest therapies for Strep zoo.

From an integrative medicine perspective, might want to address any constitutional issues–is there any underlying Wei Qi deficiency?

[sascha]

Thank you!!!

Yes, antimicrobial sensitivity testing was done.

Will keep in mind checking guttural pouches for bacterial hideout as a next diagnostic.

The first round of ABX was 3 rounds of Excenel and 3 rounds of SMZs given concurrently. The second round was 2 rounds of Excenel and 1 round of SMZs. Subsequent treatments were single treatment of one or the other with this round and the previous being Excenel as both my horse and I prefer injection. I know. We’re weird. Also, I prefer 1x day treatment when possible because I can administer myself and know that no doses get missed in the rush of morning chores when I’m not there.

Where I am at right now is gathering information to open a conversation with her current vet about doing a lengthy ABX treatment that lasts well beyond the point where she appears to have been ‘cured’ and to have him (and possibly the clinic that did the last 2 scopes for us) put their heads together with OVC to discuss possible treatment plan.

I mean this nonsense of her getting sick every few months has got to stop somehow. She’s unhappy when she’s ill and I’m broke and unhappy every few months. I’d rather go bankrupt once and have a healthy happy horse at this point.

I wish that the most awesome acupuncture/Chinese medicine vet in my area had not retired She was a godsend when same horse foundered a few years ago. I maintain I might not have had a sound horse (or a horse at all!) without her work. It was truly remarkable.

[No1]

You could also speak to them about giving Eqstim, during treatment next time. Eqstim is an immune system booster meant to aid in recovery from respiratory infections.

[sascha]

Thank you. I will reach out today as she is currently on day 2 of a treatment.

[cmdrcltr]

We’ve finally evicted Strep Zoo from our barn after seven months. My mare and her paddock mate never got it; some other horses had it two or three times. Our strain of bacteria was “eating” the SMZs, so had to switch to a different antibiotic (I’m not sure what—sorry.) Also used the immune booster on a couple of horses who seemed to be hanging on to the yuck. It’s frustrating for sure; good luck!

[SMK]

So coming at this from a microbiological standpoint. I worked for several years on chronic lung infections in cystic fibrosis and COPD patients. Of which Staph were frequent culprits.

For chronic lung infections, nebulized abx are an important tool in clearing infections. They allow abx concentrations to be much higher in the lungs than can be achieved in the blood because of toxicity.

In chronic lung infections, yes, we absolutely continue past the point in which symptoms have improved. Persister cells and biofilms are major issues in these types of infections, as likely are minor subpopulations of antibiotic resistant organisms.

New research (in humans) says viruses may play a bigger role than we once suspected in chronic lung infections, and bacteria may be secondary and opportunistic. Staph are notoriously opportunistic and often move in because an initial problem (which may or may have not resolved itself).

Take all of that with a HUGE grain of salt, because again, my research is in chronic human lung infections. But I thought I’d throw it out there, as my postdoctoral work rarely comes up in casual conversation.

-Your friendly neighborhood microbiologist

[sascha]

Thank you @SMK! This is great and is actually far more useful than my N1 of, “Hey doc, so I have this weird cat that we treated with abx daily for 6 months for a resp infection and weird blood and it worked. Let’s do it to my horse too.”