Mosquitoes in a changing environment Anders Lindström National Veterinary Institute Sweden Tree hole mosquito, Aedes geniculatus
The One health concept is the realization that we are connected to our environment and that changes in our environment will affect our health through various mechanisms. House mosquito, Culex pipiens, hatching
Why it is hard to talk about the future What we think that we know What we know that we don't know What we don't know that we don't know Yellow fever mosquito, Aedes aegypti
The mosquito fauna is changing We know climate change will affect, among other things Temperature Precipitation We also know that the mosquito fauna is changing New species are establishing in Europe Native species are changing their distribution We can see emerging mosquito- and vectorborne infections West Nile Fever Usutu Bluetongue Schmallenberg Dengue Chikungunya Malaria Zika? House mosquito, Culex pipiens larva
Blue emperor (Anax imperator) found first in 2002 on Gotland
Wasp spider(argiope bruennichi), found 1989 on Gotland
The parasitic fly Tachina ursina was first observed in Sweden in April 1994 and has spread north
Purple emperor, Apatura iris First observation 1981, exploded in the last years.
What does dragonflies, butterflies and spiders have to do with mosquitoes? They are big and easy to recognize They are all affected by climate change Who is looking for mosquitoes and how they are affected? Malaria mosquito, Anopheles messeae
What about the phenology of native species? Longer seasons means bigger populations at the end of season, which may lead to higher rates of transmission of pathogens. House mosquito, Culex pipiens, overwintering
What will the higher temperatures mean for the rest of Europe? What will happen when our native mosquitoes meet new or reemerging pathogens? Malaria mosquito, Anopheles messeae
Flooding events are calculated to be more frequent. How will that effect the flood water mosquitoes? Flood water mosquito, Aedes sticticus
One Health and mosquitoes So, the hunt was on! Trapping in likely habitats for two seasons. Nothing!
In beginning of July, while I was having dinner with my family and parents, a mosquito landed on my arm and tried to feed. I collected it, of course, and it turned out to be Culex modestus! West Nile mosquito, Culex modestus
Now we are applying for funds to determine the distribution and abundance of Cx. modestus in Southern Sweden West Nile mosquito, Culex modestus
Factors affecting distribution and abundance of two mosquito species in Camargue
Native mosquitoes should not be forgotten! Woodland mosquito, Aedes cinereus
Native mosquitoes have significant vector potential! Source: ECDC
Mosquito hunt 166 traps all over the country To map the Swedish mosquito fauna GIS data to connect trap data to habitat
Crowdsourcing Acreto AB - Imports and distributes Mosquito Magnets - Large customer network in Sweden (~15 000 sold machines) SVA - Reaches the customers/owners of the machines through Acreto AB and media - Customers sends a 24h catch sample to SVA - Acreto/SVA replaces the sent in net bags with a new one to the customers
Mosquito distribution Mosquito hunt Model Trap sites Modelled distribution based on vegetation and hydrology
Why? Climate change and globalisation means increased possiblities for mosquito borne disease. Increased knowledge of mosquito distribution give better possibilities for modeling of vectors and risk of outbreaks. Picture from nordrisk.dk!
But, mosquitoes like to travel!
Yellow fever mosquito Discovered in 1750 by Swedish traveller and naturalist Fredrik Hasselquist, described by Linnaeus in 1762. Yellow fever mosquito, Aedes aegypti
Yellow fever mosquito Had already travelled the Atlantic onboard the slave ships. The mosquitoes bred in the water supplies for the slaves and fed on the blood of the slaves. First outbreaks of Yellow fever in the Caribbean in 1647 and 1648.
Mosquitoes adapt and use the latest means of transportation!
The Tiger mosquito This mosquito originates from the forests of SE Asia, where it breed in pitcher plants, treeholes etc. Tiger mosquito, Aedes albopictus
The Tiger mosquito In 1960 China and Soviet split. Albania chose China over Soviet. This forced Albania to trade with China. One of the products that was shipped to Europe was tyres.
The Tiger mosquito The standing water in the tyres is equivalent to the small bodies of water found at forest edges that the Tiger mosquito, Aedes albopictus, breeds in.
One Health and mosquitoes The Tiger mosquito is a serious pest in Southern Europe. It is also a vector for dengue, chikungunya, zika etc. Tiger mosquito, Aedes albopictus
Since then it has succesfully travelled the world and established itself more or less everywhere. Tiger mosquito, Aedes albopictus
Japanese rock pool mosquito, Aedes japonicus. Spreading in Europe. Often found in graveyards where it breeds in flower vases on the graves.
Japanese Rock Pool Mosquito
Picture: ECDC
And that s just the mosquitoes. Outbreaks of Bluetongue and Schmallenberg viruses during the last decade. Biting midge, Culicoides sp.
Taiga tick, Ixodes persulcatus
Spinose ear tick, Otobius megnini
Thank you for listening! Anders Lindström National Veterinary Institute anders.lindstrom@sva.se