Miconazole Resistance?

Hello Summarians!

Something is shifting in the disease landscape, and the direction is worth paying attention to. A tapeworm rarely seen in the lower 48 states has now established itself in Washington coyotes at a 37% infection rate.

A yeast we've treated with the same drugs for decades is developing resistance.

And chronic gut disease in dogs is responding to dietary fiber in ways that should change how we think about it. None of this is cause for panic. But it is cause for attention.

Enjoy…

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Increased Wildlife Tapeworms

The parasite Echinococcus multilocularis is a zoonotic cestode of canids that causes alveolar echinococcosis (AE), a severe and potentially fatal disease in humans. Historically limited in distribution, this parasite has expanded across the Northern Hemisphere in recent decades, likely driven by factors such as climate change, urbanization, and human-mediated animal movement. Its life cycle is primarily sylvatic, involving wild canids like coyotes and foxes as definitive hosts and rodents as intermediate hosts, with humans and domestic dogs occasionally serving as aberrant hosts. Infection in intermediate hosts results in tumor-like cysts in the liver, leading to significant morbidity.  

Globally, AE is considered one of the most significant foodborne parasitic diseases, with approximately 18,000 new human cases annually. Although historically rare in North America, especially outside of Alaska, recent years have seen increasing detection in both wildlife and humans, particularly in Canada and parts of the United States. Notably, more virulent “European-type” strains have emerged and may contribute to the rising incidence and geographic spread.  

This study documents the first confirmed presence of E. multilocularis in wild coyotes in Washington State, indicating that the parasite has established a local transmission cycle. Analysis of 100 coyotes revealed a high infection prevalence of 37%, suggesting the parasite had been circulating undetected for several years. Molecular sequencing showed that the strain present closely matches one previously identified in British Columbia, indicating regional connectivity.  

The study also highlights diagnostic challenges. Molecular techniques such as DNA metabarcoding and intestinal swabbing were more sensitive than traditional fecal testing, which often fails due to low DNA yield or environmental degradation. These findings underscore the importance of improved surveillance methods. Overall, the emergence of E. multilocularis in the Pacific Northwest represents a growing public health concern, emphasizing the need for increased awareness, monitoring, and research into transmission dynamics and risk mitigation. 

Detection of Echinococcus multilocularis in coyotes in Washington State, USA highlights need for increased wildlife surveillance Yasmine Hentati ,Ellie Reese,Claire C. Curran,Erika M. Miller,Dakeishla M. Díaz-Morales,Samantha E.S. Kreling,Guilherme G. Verocai,Laura R. Prugh,Christopher J. Schell,Chelsea L. WoodPublished: March 24, 2026 https://doi.org/10.1371/journal.pntd.0013502

Bottom line — Means higher risk for all exposed.

New Resistance Patterns For Moconazole

Otitis externa (OE) is a common inflammatory condition in dogs, affecting up to 20% of cases seen in veterinary practice worldwide. It is often associated with underlying allergic disease and frequently complicated by secondary infections, particularly with the yeast Malassezia pachydermatis. Standard treatment for Malassezia-associated OE typically involves topical or systemic azole antifungal medications, often combined with glucocorticoids to reduce inflammation and address the underlying condition. However, increasing reports of persistent or recurrent infections have raised concern about emerging antifungal resistance, particularly to commonly used agents such as miconazole. 

This study aimed to evaluate the susceptibility of M. pachydermatis isolates from dogs with OE to miconazole and to investigate the genetic mechanisms underlying reduced susceptibility. Using disk diffusion assays, the researchers found a wide range of responses to miconazole, including isolates that showed clear resistance. These findings support the idea that antifungal resistance can develop with repeated or prolonged clinical use of azole medications. 

Phylogenetic analysis revealed that the isolates clustered into three major clades, indicating genetic diversity within the population. By examining the ERG11 gene, which encodes the target enzyme lanosterol 14α-demethylase, the study identified specific amino acid substitutions associated with decreased miconazole susceptibility. In particular, substitutions at position A302 were strongly linked to resistance, likely due to their location within the drug-binding site of the enzyme, which interferes with effective antifungal binding. 

Importantly, the study distinguished between mutations that genuinely affect drug susceptibility and those that are simply associated with phylogenetic grouping. This distinction helps clarify conflicting findings in previous research. Overall, the results highlight the clinical relevance of emerging antifungal resistance in canine OE and underscore the need for improved susceptibility testing methods, molecular diagnostics, and responsible antifungal use to preserve treatment efficacy 

C. M.Belcher, C. P.Souza, E.McGuire, C.-C.Hung, J. D. A.Tyndall, and L. L.Hoyer, “Phylogenetic and Structural Analysis of Miconazole Susceptibility in Malassezia pachydermatis Isolates From Dogs With Otitis Externa,” Veterinary Dermatology (2026): 1–10, https://doi.org/10.1111/vde.70059

Bottom line — Important development in yeast treatment.

Fiber And Enteropathy

Canine chronic enteropathy (CE) is a syndrome characterized by persistent gastrointestinal signs lasting longer than three weeks after extraintestinal causes have been excluded. It is typically classified based on response to treatment trials, including food-responsive enteropathy (FRE), microbiota-related enteropathy, immunosuppressive-responsive enteropathy (IRE), and nonresponsive enteropathy (NRE). Despite histopathologic confirmation of inflammation, no diagnostic test reliably predicts treatment response, so management relies on sequential therapeutic trials, most often beginning with dietary modification. 

FRE represents the most common subtype, accounting for approximately two-thirds of cases. Although hydrolyzed protein and limited-ingredient diets are commonly used to reduce antigenic stimulation, remission can occur with a wide range of diet types, highlighting the complexity of CE pathogenesis. Recent research suggests that dietary strategies can even induce remission in dogs previously categorized as having refractory disease or allow reduction of immunosuppressive therapy, emphasizing the importance of diet beyond simple antigen restriction. 

Dietary fiber has emerged as a potentially important but underutilized component of CE management. Fiber influences gastrointestinal physiology by altering stool quality, transit time, and nutrient absorption, while also exerting effects on the intestinal microbiome and immune system. These effects are partly mediated through the production of short-chain fatty acids during fermentation, which can support mucosal health and modulate inflammation. However, the impact of fiber depends on its type, amount, and properties such as fermentability and solubility, and standardized recommendations for its use in CE are lacking. 

This study investigated whether increasing dietary fiber intake could improve clinical outcomes in dogs with CE. Results demonstrated that higher fiber intake was associated with improved fecal consistency and reduced clinical disease activity in most dogs, including those previously unresponsive to other dietary approaches. These findings suggest that fiber-responsive enteropathy may represent an important subset of CE and support the inclusion of fiber modification as a therapeutic strategy, although further prospective research is needed to define optimal fiber types and dosing. 

Ford-Hrymak, D. B., Rudinsky, A. J., Muirragui, I., Landau, E. D., Rowe, J. C., Winston, J. A., & Parker, V. J. (2026). Increased dietary fiber intake improves fecal and clinical activity scores in dogs with chronic enteropathy. Journal of the American Veterinary Medical Association https://doi.org/10.2460/javma.25.12.0868 

Bottom line — Fiber is an important consideration in dogs.

Just putting things in perspective …