I do like working underground, but it's a bit strange to go outside you feel a bit like vampire
It was a pretty hot environment to work in but the mosquitoes like it
We're at London school of Hygiene and tropical medicine. It's on a busy street, but a lot of people don't realize that
They're walking on top of underground labs that are home to thousands of mosquitoes from across the world
These used to be air-raid shelters in world war two they were converted to insectaries in 1960s
When I first started working here, it was terrible because it was just you're not used to it
You're not used to the heat, and you're not very good at moving the mosquitoes
Everything's difficult and takes you a long time. So you spend a lot longer down here, but you soon acclimatize to the conditions
So basically we bear insects such as mosquitoes to test products like insect repellents
We do the development work here to check that they work before they're sold to the public
It's important to test repellents against mosquitoes because they can transmit diseases such as dengue Malaria West Nile virus
So we want to prevent that happening
And going to blood feed the mosquitoes, so they can produce their eggs
They need it for egg development, and you won't see their bellies filling up with blood
[sir] female mosquito. She has biting wrap up shield blood feed she'll feed on human Whereas their males
Just feed on sugar. They don't have the same mouth parts
When we do testing we just select females I?
do not like these females we get bitten by them quite frequently so
Feels like a little bit of revenge when we get to test on them
So this is where they test the mosquito repellents
And the only way to see if a repellent is working is to actually try it out
Basically we have a control arm and a treatment arm. So your control arm has nothing on and
The treatment arm will have the repellent on and what I promise these are these are sting amira gypped
I so these are daytime biters and these transmit dengue
Those tests again. Yes trained
Certainly we close it up and start the timer be familiar yes, so you can see there's loads already on my arms
Okay, okay, okay? Shake girl. Can you feel them no?
I very slightly yeah, you can see the tiny little red marks there, and I bet by tomorrow. There's a few big bumps
And lastly to land on your skin, and it will [pinch] your skin with this proboscis
and it finds a capillary the proboscis actually can move like this and
Skin they pierced with pillory and they inject an anticoagulant in their saliva to prevent the blood clotting so they can continue
Sucking it up, and then your body producing immune response, so that's why you get the information where a bite has been
If the repellent works there should be no mosquitoes on your arm
Yeah, you can see already, but just not really interested are they their bites on this arm the repellent works
So what [lo] different species of mosquitoes to come from all over the world so Tanzania, India Southeast, Asia?
Mosquitoes we work with a lab have never been exposed to any parasites
They literally go through their life cycle there, and we've kept them in colony since 1960s really
This is a math aspirator. This is how we transport the mosquitoes from a cage to a cup so this?
filters all the scales that might come off the mosquitos bodies, and so they don't go into our lungs, so
[this] is the free flight room where we're going to be testing some repellent clothing
yeah, I've got my
aspirator here
So if any do [I'm] [going] which they should I don't actually have to let them wait [for] too long
I can just set them up
this is quite scary in the free fly room if you're locked in there by yourself left to count Mosquitos, [so]
I'm going out the door
We've got a string attached [to] the cup and I'm going to pull this when I go outside the door
So I didn't get bitten and they're going to be unleashed on the kids said
There's one hand very interested in me. Yeah, she is going for it
I'm going to call it three and then there's been at least five
That I've counted on the rest of my body in jail managed to set up so now we've done the control test
We're going to test the treatment. Which is these?
insecticide impregnated clothes
So I put a few buzzing around me, but none of them have actually landed yet. I've got one here
Repellents work by confusing the Mosquito they interfere with their ability to find a human host
So that you're sort of masked and they they can't find you essentially
They're one Mosquito. Isn't too bad, considering how many you will landing on me without these clothes
This is our morgue
This is where we put all the mosquitoes to die after testing. We only use mosquitoes once
So we don't transmit diseases to anyone, and then they go in here, and they don't have it any food and they die