Transmission of arthropod-borne viruses (arboviruses) involves infection and replication in both arthropod vectors and vertebrate hosts. Nearly all arboviruses are RNA viruses with high mutation frequencies, which leaves them vulnerable to genetic drift and fitness losses owing to population bottlenecks during vector infection, dissemination from the midgut to the salivary glands and transmission to the vertebrate host. However, despite these bottlenecks, they seem to avoid fitness declines that can result from Muller’s ratchet. In addition, founder effects that occur during the geographic introductions of human-amplified arboviruses, including chikungunya virus and Zika virus, can affect epidemic and endemic circulation, as well as virulence. In this Review, we discuss the role of genetic drift following population bottlenecks and founder effects in arboviral evolution and spread, and the emergence of human disease.

节肢动物传播的病毒（虫媒病毒）的传播涉及节肢动物载体和脊椎动物宿主的感染和复制。几乎所有虫媒病毒都是具有高突变频率的RNA病毒，这使得它们容易受到遗传漂移和适应性损失的影响，因为在媒介感染、从中肠传播到唾液腺以及传播到脊椎动物宿主期间存在群体瓶颈。然而，尽管存在这些瓶颈，他们似乎避免了穆勒棘轮可能导致的体能下降。此外，人类扩增的虫媒病毒（包括基孔肯雅病毒和寨卡病毒）在地理上的引入过程中发生的创始人效应可能会影响流行病和地方性流行以及毒力。在这篇综述中，我们讨论了种群瓶颈后遗传漂变的作用以及虫媒病毒进化和传播以及人类疾病的出现中的奠基者效应。