A new initiative, the Mosquito-Associated Isolate Collection ( MosAIC), aims to address global health challenges posed by vector-borne diseases by cataloguing bacteria associated with mosquitoes. These diseases account for over 17 per cent of all infectious diseases globally, causing more than 700,000 deaths annually, according to the World Health Organisation. Malaria alone results in an estimated 249 million cases and over 608,000 deaths each year, with children under five being the most affected.
Pathogens transmitted by blood-feeding insects, including mosquitoes, are responsible for diseases such as dengue fever and Zika virus-related birth defects. The effects of climate change could further increase the prevalence of mosquito and tick-borne diseases in regions like the UK. Multiple encephalitis cases have already been identified, prompting the UK Health Security Agency to establish an early warning system to detect outbreaks as mosquito habitats expand.
Researchers from the UK and the USA have collaborated to create MosAIC, the first large-scale repository of mosquito-associated microbiomes, which includes genome data and bacterial isolates. This resource aims to reveal how bacteria within the mosquito microbiome influence the insect’s ability to transmit viruses.
The collection has been developed through contributions from researchers across the mosquito research community, who provided bacterial isolates either directly from mosquitoes or their habitats. These isolates were whole-genome sequenced to create an open-access database alongside a culture collection.
The mosquito microbiome is dynamic and influenced by factors such as host species, geography, and the mosquito’s life stage. There are more than 3,700 mosquito species worldwide, yet their microbiomes remain poorly understood. These microbiomes impact the mosquito’s capacity to transmit viruses and its susceptibility to virus transmission.
With rising insecticide resistance, microbiome manipulation presents a potential alternative for disease control. Researchers hope that by cataloguing bacterial diversity, this initiative will lead to better disease transmission understanding and innovative control strategies.
The project findings were published in PLOS Biology. Dr Eva Heinz from the University of Strathclyde said, “We don’t have enough understanding yet of mosquito microbiomes. With the increase of insecticide resistance and the need for new approaches, this collection could help us create a new tool for vector controls.
“It offers a unique, highly valuable resource for research on bacterial colonisation and adaptation within mosquito hosts. Already we have increased the number of mosquito-associated bacterial genomes by more than ten times, from 35 to 392. It’s a huge step to understanding what is there and can be accessed by researchers. Improvements in malaria control are stalling, and insecticide, as well as antimalarial resistance spread, means we are losing control tools.”
The project was co-led by researchers from the University of Wisconsin-Madison in the USA, Liverpool School of Tropical Medicine, and the University of Salford in the UK, with contributions from ten labs across the mosquito research community.
Laura Brettell, University Fellow at the University of Salford, added, “In the future, the insights gained from this work could lead to the development of much needed novel ways to harness naturally occurring bacteria to combat mosquito-borne diseases – tackling a critical global health challenge.”
The project is funded by the U.S. National Science Foundation and the UKRI Biotechnology and Biological Sciences Research Council (BBSRC).