IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
Unitat mixta d'Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
J Gen Virol. 2024 Sep;105(9). doi: 10.1099/jgv.0.002025.
Rift Valley fever virus (, RVFV) poses significant economic challenges, particularly in African nations, causing substantial livestock losses and severe haemorrhagic disease in humans. In Europe, the risk of RVFV transmission is deemed moderate due to the presence of competent vectors like and , along with susceptible animal vertebrate hosts across member states. This study investigates RVFV infection dynamics in European mosquito populations, aiming to enhance our understanding of their vectorial capacity and virus transmission, which can be useful for future investigations to improve RVFV surveillance, control programmes, and preventive treatments. Intrathoracic inoculation of European and with an RVFV virulent strain (RVF 56/74) enabled the assessment of virus tissue distribution and transmission. Immunohistochemistry analyses revealed widespread RVFV infection in all analysable anatomical structures at 5 and 14 days post-inoculation. Notably, the ganglionic nervous system exhibited the highest detection of RVFV in both species. showed more frequently infected structures than , particularly in reproductive structures. The identification of an RVFV-positive egg follicle in hints at potential vertical transmission. Saliva analysis indicated a higher transmission potential in (71.4%) compared to (4.3%) at the early time point. This study offers the first description and comparison of RVFV tissue distribution in and , shedding light on the susceptibility of their nervous systems, which may alter mosquito behaviour, which is critical for virus transmission. Overall, enhancing our knowledge of viral infection within mosquitoes holds promise for future vector biology research and innovative approaches to mitigate RVFV transmission.
裂谷热病毒（RVFV）对经济造成重大挑战，尤其在非洲国家，导致大量牲畜损失，并使人类罹患严重出血性疾病。在欧洲，由于存在 和 等媒介，以及成员国中易感动物脊椎宿主，认为 RVFV 传播的风险为中等。本研究调查欧洲蚊子种群中的 RVFV 感染动态，旨在增进对其媒介能力和病毒传播的理解，这对于未来的调查研究，以改善 RVFV 监测、控制方案和预防治疗有用。用 RVFV 强毒株（RVF 56/74）对欧洲 和 进行胸内接种，可评估病毒的组织分布和传播。免疫组织化学分析显示，在接种后 5 天和 14 天，所有可分析的解剖结构中均广泛感染 RVFV。值得注意的是，两种蚊种的神经节神经系统中 RVFV 的检出率最高。 比 更容易感染结构，尤其是生殖结构。在 中发现一个 RVFV 阳性的卵滤泡，提示可能存在垂直传播。唾液分析表明，在早期时间点， 的传播潜力（71.4%）高于 （4.3%）。本研究首次描述和比较了 和 中的 RVFV 组织分布，揭示了其神经系统的易感性，这可能改变蚊子的行为，这对病毒传播至关重要。总体而言，增进我们对蚊子体内病毒感染的了解，为未来的媒介生物学研究和减轻 RVFV 传播的创新方法提供了前景。
