Kelvin Alyson A, Baker Pari H, Ghosh Sourish, Schultz-Cherry Stacey, Langel Stephanie N
Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.
Department of Pathology, Center for Global Health and Diseases, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
J Virol. 2025 Sep 23;99(9):e0194024. doi: 10.1128/jvi.01940-24. Epub 2025 Aug 12.
The mammary gland is an essential organ for milk production, providing essential immune and nutritional support to offspring and supplying dairy products for human consumption. In both humans and animals, the lactating mammary gland is susceptible to bacterial and viral infections, which can lead to mastitis and, in some cases, vertical transmission to offspring, with potential adverse effects on infant health. However, until recently, the role of respiratory viruses in mammary gland infection has been relatively understudied, particularly their ability to infect mammary epithelial cells and transmit through lactation. The recent emergence of highly pathogenic avian influenza H5N1 clade 2.3.4.4b in dairy cattle has demonstrated the virus's capacity to replicate in the mammary gland, cause mastitis, and produce high viral loads in milk. This raises significant concerns about the potential for zoonotic transmission to humans and other animals in contact with infected dairy cows and unpasteurized milk. In this mini-review, we highlight key studies that demonstrate the replication of influenza and other viruses in the mammary gland, summarize recent findings from experimental and natural H5N1 clade 2.3.4.4b infections in dairy cows and small animal models, and discuss the broader One Health implications of the current H5N1 outbreak. We emphasize the urgent need for an interdisciplinary collaboration across sectors to mitigate the risks posed by influenza viruses with pandemic potential.
乳腺是产奶的重要器官，为后代提供重要的免疫和营养支持，并为人类消费提供乳制品。在人类和动物中，泌乳期的乳腺易受细菌和病毒感染，这可能导致乳腺炎，在某些情况下，还会垂直传播给后代，对婴儿健康产生潜在不利影响。然而，直到最近，呼吸道病毒在乳腺感染中的作用相对较少受到研究，特别是它们感染乳腺上皮细胞并通过乳汁传播的能力。高致病性禽流感H5N1进化分支2.3.4.4b最近在奶牛中出现，证明了该病毒在乳腺中复制、引起乳腺炎以及在乳汁中产生高病毒载量的能力。这引发了人们对该病毒可能传染给接触受感染奶牛和未杀菌牛奶的人类及其他动物的严重担忧。在本综述中，我们重点介绍了证明流感病毒和其他病毒在乳腺中复制的关键研究，总结了奶牛和小动物模型中H5N1进化分支2.3.4.4b实验性感染和自然感染的最新发现，并讨论了当前H5N1疫情对“同一健康”的更广泛影响。我们强调迫切需要跨部门开展跨学科合作，以降低具有大流行潜力的流感病毒带来的风险。
