New paper looks at how infection with the filarial parasite influences mosquito behaviour.

News article 1 Nov 2016

Researchers at LSTM have gone a step further in understanding the role that parasitic infection plays in the host seeking behaviour of mosquitoes responsible for the transmission of lymphatic filariasis.

Lymphatic filariasis (LF) is a neglected tropical disease (NTD) and one of the largest causes of permanent and long term disability worldwide. Caused by three species of filarial nematodes, and transmitted by several species of mosquito, there are an estimated 120 million human cases of LF across 55 different countries. As we move towards the endpoint goals set by the Global Programme for the Elimination of Lymphatic Filariasis (GPELF), understanding the interactions between vector and parasite becomes increasingly important.

In a paper published this week in the journal Scientific Reports, research assistant Katherine Gleave and colleagues looked at the how infection with Brugia malayi influences the behaviour of Aedes aegypti mosquitoes during different stages of parasite development. The paper is based on Ms Gleave’s MSc thesis, which previously won best poster prize at the Royal Society of Tropical Medicine and Hygiene and looks at how mosquitoes behave during different stages of the parasite’s development.

Previous studies looking at infection with the Plasmodium parasite, which causes malaria, has shown a difference in behavioural characteristics which appear to be stage-specific. Ms Gleave said: “In a similar way we found a change in mosquito behaviour could be a direct parasite mediated and stage specific dependent mechanism, potentially driving a suppression of behaviour during the development phase to protect the parasite from the risks associated with blood feeding. However this behaviour was reversed during the parasite’s infective phase, in order to facilitate parasite transmission to the definitive host.”

The paper calls for more research to look at the extent that these patterns of host-seeking behaviour change, extending to wild vectors of filariasis and the impact that this might have on endpoint elimination targets. Dr Lisa Reimer, senior author on the paper, said: “As we move towards the goal of vector-borne disease elimination, it has never been more important that we understand the relationships between the vector and the parasite and how that can impact on host-seeking behaviour and disease transmission.”

You can read the full paper here.