Unraveling Arbovirus Emergence: Insights into the Molecular Switch from Vector to Host

The COVID-19 pandemic is a dramatic reminder of the problems that viral zoonoses can cause worldwide. The rapid development of vaccines and antivirals against SARS-CoV-2 was only possible because the structural and functional biology of other coronaviruses was already known. This knowledge is often lacking for other emerging viruses. An illustration is the supergroup of arthropod-borne viruses (arboviruses), whose spread is accelerated by global warming and human activities. Yet these viruses have a high potential for emergence in humans and livestock. Ideally, preventing the spread of arboviruses and other zoonotic viruses requires approaches that target early stages of transmission and virus-host cell interactions, which is precisely the focus of this lecture. First, I will introduce arboviruses and explain why it is biologically relevant to study these viruses. We will then briefly discuss the complex life cycle of arboviruses in both arthropods and mammals, which vary significantly in their molecular and cellular biology. I will then provide general principles on the transmission of these viruses to human and mammalian hosts by their arthropod vectors. Finally, we will discuss in detail how this vector-host transition is used by arboviruses at the molecular and cellular levels to promote their transmission and spread.

Learning Objectives:

1. Describe the biological relevance of studying arboviruses, including their potential for spillover into human and livestock populations.

2. Explain the complex life cycles of arboviruses within arthropod and mammalian hosts, highlighting the significant variations in molecular and cellular biology involved.

3. Analyze and discuss the molecular and cellular mechanisms employed by arboviruses during the vector-host transition, specifically focusing on their strategies for transmission and spread.