Control of bovine tuberculosis (bTB), caused by Mycobacterium bovis , in the Republic of Ireland costs €84 million each year. Badgers are recognized as being a wildlife source for M. bovis infection of cattle. Deer are thought to act as spillover hosts for infection; however, population density is recognized as an important driver in shifting their epidemiological role, and deer populations across the country have been increasing in density and range. County Wicklow represents one specific area in the Republic of Ireland with a high density of deer that has had consistently high bTB prevalence for over a decade, despite control operations in both cattle and badgers. Our research used whole-genome sequencing of M. bovis sourced from infected cattle, deer and badgers in County Wicklow to evaluate whether the epidemiological role of deer could have shifted from spillover host to source. Our analyses reveal that cattle and deer share highly similar M. bovis strains, suggesting that transmission between these species is occurring in the area. In addition, the high level of diversity observed in the sampled deer population suggests deer may be acting as a source of infection for local cattle populations. These findings have important implications for the control and ultimate eradication of bTB in Ireland.

中文翻译：

---

牛分枝杆菌基因组学揭示了爱尔兰牛和鹿之间的感染传播。


爱尔兰共和国每年花费 8,400 万欧元来控制由牛分枝杆菌引起的牛结核病 (bTB)。獾被认为是牛感染牛支原体的野生动物来源。鹿被认为是感染的溢出宿主；然而，人口密度被认为是改变其流行病学作用的重要驱动因素，全国各地的鹿种群密度和范围一直在增加。威克洛郡是爱尔兰共和国鹿密度较高的一个特定地区，尽管对牛和獾采取了控制措施，但十多年来，该地区的牛结核病患病率一直很高。我们的研究使用了来自威克洛郡受感染牛、鹿和獾的牛支原体的全基因组测序来评估鹿的流行病学作用是否可能已从溢出宿主转移到来源。我们的分析表明，牛和鹿具有高度相似的牛支原体菌株，这表明该地区正在发生这些物种之间的传播。此外，在鹿群样本中观察到的高水平多样性表明鹿可能是当地牛群的感染源。这些发现对于爱尔兰控制和最终根除 bTB 具有重要意义。