Arthropod-borne infections

Arthropod-borne infections

This programme aims to better understand mosquito-virus interactions, including antiviral innate immunity, vector competence and the inhibitory effects of symbionts such as Wolbachia on transmission; to provide potential new strategies for vector control; and to understand arbovirus replication and vertebrate immune responses to infection.


Approximately thirty percent of all infectious diseases that emerged in the last decade are caused by arthropod-borne viruses (arboviruses). Arboviruses are transmitted by biting arthropods like mosquitoes, midges and ticks. The mosquito-borne, medically relevant viruses are grouped into three families:

Bunyaviridae, segmented negative strand RNA viruses
Flaviviridae, non-segmented positive strand viruses (genus Flavivirus)
• Togaviridae, non-segmented positive strand viruses (genus Alphavirus)

However other important arboviruses are transmitted are transmitted by midges (blue tongue, Schmallenberg and Oropouche viruses for example) or ticks (tick-borne encephalitis virus, Crimean-Congo hemorrhagic fever virus of example). The bite of an infected insect (e.g. mosquito or midge) can transmit the virus to a susceptible animal or human, and give rise to serious disease. Traditionally, arboviruses were present only in tropical and sub-tropical areas of the world but climate change and globalization have expanded the geographical reach of these infections.

The human pathogenic alphavirus chikungunya virus (CHIKV) and the flaviviruses dengue (DENV) and Zika (ZIKV) are now very important pathogens in many countries worldwide.

Our overarching goal is to better understand mosquito-arbovirus interactions, and how to control arbovirus infection. 

Arboviruses must establish a balance between replication and vector survival in the mosquitoes in order to be transmitted to the mammalian hosts. The immune system of insect vectors allows arbovirus replication, but at the same time avoids the pathogenic repercussions. Yet even within the same species, there are important (individual) differences regarding the ability of mosquitoes to transmit arboviruses: this phenomenon is called “vector competence”, and the basis of these differences in natural as well as laboratory populations is poorly understood.

Understanding how the mosquito vector responds to arbovirus infections will unveil key determinants of vector competence, and at the same time identify targets for genetic manipulation that can offer new strategies for vector control

In this programme we aim to dissect the RNAi system in the mosquito, which are the main effectors that control arbovirus infection. We also study the mechanisms by which inherited Wolbachia symbionts can block arbovirus transmission by mosquitoes, and how this can be exploited for the control of DENV and other viruses.

Moreover, we study interactions of arboviruses with their vertebrate hosts. That part of the programme aims to understand immune responses as well as viral inhibition if immune responses. Moreover, we investigate viral replication strategies and protein interactions in a range of arboviruses.

Programme members

Alain Kohl

Programme Leader Track

Emilie Pondeville

Research Fellow


Massimo Palmarini

Chair of Virology


Steven Sinkins

Professor in Microbiology and Tropical Medicine