Study links resistant Salmonella in houbara bustard to UAE broilers: full analysis
A newly published Frontiers in Veterinary Science paper reports the genomic characterization of an mcr-1.1-positive, multidrug-resistant Salmonella Kentucky ST198 isolate from a captive Asian houbara bustard in the United Arab Emirates, with sequencing data linking it closely to previously described UAE broiler poultry isolates. The study centers on a single isolate, FAZ18016, recovered from yolk sac samples during post-mortem examination, but its significance reaches beyond one bird: it points to possible spillover of a high-risk antimicrobial resistance lineage from commercial poultry into a vulnerable captive wildlife population. (frontiersin.org)
That finding lands in an important conservation and One Health context. The Asian houbara bustard is a vulnerable species supported by conservation breeding programs in the UAE and elsewhere, and the paper notes that antimicrobial-resistant infections are an emerging threat in captive populations. At the same time, Salmonella Kentucky ST198 is not an obscure lineage. It has been described for years as an internationally disseminated resistant clone, with poultry repeatedly implicated as a likely vehicle, including in reports tied to travel-associated human infection. (frontiersin.org)
The genomic details are what make this study especially notable. The isolate showed phenotypic resistance to 17 antimicrobials and carried 21 resistance determinants, including blaTEM-1, mph(A), tet(A), floR, sul1/sul3, and mcr-1.1. Its colistin MIC was 8 mg/L. The mcr-1.1 gene sat on an IncHI2 plasmid that also carried other resistance-associated features and shared more than 99% nucleotide identity with plasmids previously described in Klebsiella pneumoniae and Escherichia coli, underscoring the mobility of the resistance element itself. The strain also carried 156 virulence-associated genes, including complete SPI-1 and SPI-2 regions and type III and type VI secretion system components. (frontiersin.org)
The phylogenomic comparison strengthens the poultry link. Core-genome SNP analysis placed the isolate within ST198 and found it was 31 to 166 SNPs away from previously characterized UAE broiler isolates, with the nearest strains differing by just 31 to 33 SNPs. The authors interpret that as consistent with relatively recent common ancestry, not proof of direct transmission, but enough to support concern about movement of resistant clones across the wildlife-poultry boundary. That concern fits with earlier UAE poultry research showing that mcr-1-carrying Enterobacterales were widespread in sampled broiler farms, with 36 of 40 composite samples yielding mcr-1-positive colonies and multiple transferable plasmid types identified, including IncHI2. (frontiersin.org)
Direct outside commentary on this specific paper appears limited so far, but the broader expert view is consistent: antimicrobial resistance can spread at wildlife-livestock interfaces, and biosecurity gaps create opportunities for exchange in both directions. A recent review on AMR at wildlife-urban and wildlife-livestock interfaces argues that awareness and targeted mitigation can reduce risk across these contact zones. Inference: this houbara case is likely to be read less as an isolated oddity and more as a warning signal for conservation programs operating near food-animal production systems. (pubmed.ncbi.nlm.nih.gov)
Why it matters: For veterinarians, especially those in avian medicine, zoological medicine, pathology, preventive medicine, and production-animal health, the paper is a reminder that antimicrobial resistance surveillance can’t stop at clinical cases in domestic species. Captive wildlife collections may be exposed through feed supply, personnel movement, environmental contamination, shared vendors, or other indirect pathways. The presence of plasmid-mediated colistin resistance is particularly concerning because mcr genes can move between bacterial hosts, potentially complicating treatment decisions and outbreak control. Even when a case count is low, the operational implications are immediate: tighter sourcing review, stronger sanitation barriers, more deliberate necropsy culture and sequencing protocols, and closer coordination between wildlife and poultry health teams. (frontiersin.org)
There’s also a public health angle. ST198 has a long track record as a resistant Salmonella lineage with poultry associations, and earlier CDC reporting described ciprofloxacin-resistant S. Kentucky ST198 in people, with poultry implicated as the most likely vehicle in the international spread of that sequence type. This new report doesn’t establish a human transmission event, but it does reinforce how animal-sector reservoirs, mobile resistance plasmids, and conservation settings can intersect in ways that matter across species. (wwwnc.cdc.gov)
What to watch: The next step will be whether surveillance expands beyond this single bustard isolate to include additional captive birds, environmental sampling, feed and hatchery inputs, and side-by-side comparison with contemporary poultry isolates in the UAE. If more linked strains turn up, this paper could become an early marker of a larger biosecurity and antimicrobial stewardship problem at the conservation-production interface. (frontiersin.org)