TEDxLondon
James Logan: How we're using dogs to sniff out malaria
Filmed:
Readability: 3.8
218,541 views
What if we could diagnose some of the world's deadliest diseases by the smells our bodies give off? In a fascinating talk and live demo, biologist James Logan introduces Freya, a malaria-sniffing dog, to show how we can harness the awesome powers of animal scent to detect chemical signatures associated with infection -- and change the way we diagnose disease.
James Logan - Biologist, medical entomologist
Professor James Logan leads an internationally renowned research program at the London School of Hygiene and Tropical Medicine, presents television programs and has a passion for science and natural history. Full bio
Professor James Logan leads an internationally renowned research program at the London School of Hygiene and Tropical Medicine, presents television programs and has a passion for science and natural history. Full bio
Double-click the English transcript below to play the video.
00:13
Malaria is still one of the biggest
killers on the planet.
killers on the planet.
0
1267
5156
00:18
Despite us making significant progress
in the last 20 years,
in the last 20 years,
1
6862
4920
00:23
half the world's population
is still at risk from this disease.
is still at risk from this disease.
2
11806
4492
00:28
In fact, every two minutes,
3
16322
1869
00:30
a child under the age of two
dies from malaria.
dies from malaria.
4
18215
4700
00:34
Our progress has undoubtedly stalled.
5
22939
3225
00:38
Now we face many challenges
when it comes to tackling malaria,
when it comes to tackling malaria,
6
26188
5571
00:43
but one of the problems that we have
7
31783
1817
00:45
is actually finding people who are
infected with malaria in the first place.
infected with malaria in the first place.
8
33624
4389
00:50
So, for example, if people have
some level of immunity to the disease,
some level of immunity to the disease,
9
38037
4507
00:54
then they can develop an infection
and become infectious and still pass it on
and become infectious and still pass it on
10
42568
4515
00:59
but not actually develop any symptoms,
11
47107
2009
01:01
and that can be a big problem,
because how do you find those people?
because how do you find those people?
12
49140
3326
01:04
It's like looking
for a needle in a haystack.
for a needle in a haystack.
13
52490
2788
01:07
Now scientists have been trying
to solve this problem for some years,
to solve this problem for some years,
14
55743
4652
01:12
but what I want to talk to you about today
15
60419
2016
01:14
is that the solution to this problem
may have been right under our noses
may have been right under our noses
16
62459
4539
01:19
this whole time.
17
67022
1800
01:20
Now that was a bit of a heavy start,
with lots of really important statistics,
with lots of really important statistics,
18
68846
3738
01:24
so I want us all
to just relax a little bit
to just relax a little bit
19
72608
2083
01:26
and that'll help me to relax
a little bit as well.
a little bit as well.
20
74715
2377
01:29
So why don't we just all take
a nice deep breath in ...
a nice deep breath in ...
21
77116
2936
01:32
Wow. (Laughs)
22
80076
1555
01:33
And sigh,
23
81655
1237
01:34
and, whoo, going to get blown away there.
24
82916
2896
01:37
OK, now I want you to do it again,
25
85836
1763
01:39
but this time, I want you to do it
just through your nose,
just through your nose,
26
87623
3151
01:42
and I want you to really sense
the environment around you.
the environment around you.
27
90798
3705
01:46
And in fact, I want you to really smell
the person who's sitting next to you.
the person who's sitting next to you.
28
94527
3715
01:50
Even if you don't know them, I don't care.
29
98266
2000
01:52
Lean in, get your nose
right into their armpit,
right into their armpit,
30
100290
2191
01:54
come on, stop being so British about it,
31
102505
1985
01:56
get your nose into the armpit,
have a good old sniff,
have a good old sniff,
32
104514
3422
01:59
see what you can smell.
33
107960
1595
02:01
(Laughter)
34
109579
3070
02:05
Now each and every one of us
35
113333
1856
02:07
would have had a very different
sensory experience there.
sensory experience there.
36
115213
3614
02:10
Some of us would have smelled
something rather pleasant,
something rather pleasant,
37
118851
2692
02:13
perhaps somebody's perfume.
38
121567
1443
02:15
But some of us might have smelled
something a little bit less pleasant,
something a little bit less pleasant,
39
123034
3335
02:18
perhaps somebody's
bad breath or body odor.
bad breath or body odor.
40
126393
4340
02:22
Maybe you even smelled your own body odor.
41
130757
2326
02:25
(Laughter)
42
133107
1412
02:27
But, you know, there's probably
a good reason
a good reason
43
135142
2112
02:29
that some of us
don't like certain body smells.
don't like certain body smells.
44
137278
3610
02:33
Throughout history,
45
141892
1424
02:36
there have been many examples of diseases
being associated with a smell.
being associated with a smell.
46
144646
4224
02:40
So, for example, typhoid apparently
smells like baked brown bread,
smells like baked brown bread,
47
148894
4586
02:45
and that's quite a nice smell, isn't it,
48
153504
1906
02:47
but it starts to get a little bit worse.
49
155434
2136
02:49
TB smells like stale beer,
50
157594
2204
02:51
and yellow fever smells like the inside
of a butcher shop, like raw meat.
of a butcher shop, like raw meat.
51
159822
4904
02:56
And in fact, when you look
at the sort of words that are used
at the sort of words that are used
52
164750
2876
02:59
to describe diseases,
53
167650
1555
03:01
you tend to find these words:
54
169229
1770
03:03
"rotting," "foul," "putrid" or "pungent."
55
171023
4494
03:07
So it's no surprise, then,
56
175541
1270
03:08
that smell and body odor
gets a bit of bad reputation.
gets a bit of bad reputation.
57
176835
3277
03:12
If I was to say to you, "You smell,"
58
180556
2809
03:15
now, you're going to take that
not exactly as a compliment, are you.
not exactly as a compliment, are you.
59
183389
4329
03:19
But you do smell.
60
187742
1244
03:21
You've just found that out. You do smell.
61
189010
1955
03:22
It's a scientific fact.
62
190989
1489
03:25
And I'd quite like
to turn that on its head.
to turn that on its head.
63
193087
2128
03:27
What if we could actually
think about smell in a positive way,
think about smell in a positive way,
64
195239
2916
03:30
put it to good use?
65
198179
1151
03:31
What if we could detect the chemicals
66
199354
1850
03:33
that are given off
by our bodies when we're ill,
by our bodies when we're ill,
67
201228
2749
03:36
and use that to diagnose people?
68
204001
3002
03:39
Now we'd need to develop good sensors
that would allow us to do this,
that would allow us to do this,
69
207027
3834
03:42
but it turns out that the world's
best sensors actually already exist,
best sensors actually already exist,
70
210885
5087
03:47
and they're called animals.
71
215996
2532
03:50
Now animals are built to smell.
72
218552
2040
03:52
They live their everyday lives
according to their nose.
according to their nose.
73
220616
3530
03:56
They sense the environment,
74
224170
1319
03:57
which tells them
really important information
really important information
75
225513
2189
03:59
about how to stay alive, essentially.
76
227726
1988
04:01
Just imagine you're a mosquito
77
229738
2115
04:03
and you've just flown in from outside
and you've entered this room.
and you've entered this room.
78
231877
3183
04:07
Now you're going to be entering
a really complex world.
a really complex world.
79
235084
2723
04:09
You're going to be bombarded
with smells from everywhere.
with smells from everywhere.
80
237831
2668
04:12
We've just found out
that we're really smelly beasts.
that we're really smelly beasts.
81
240523
2478
04:15
Each one of us is producing
different volatile chemicals.
different volatile chemicals.
82
243025
2709
04:17
It's not just one chemical, like BO --
83
245758
1954
04:19
lots and lots of chemicals.
84
247736
1421
04:21
But it's not just you,
it's the seats you're sitting on,
it's the seats you're sitting on,
85
249181
2714
04:23
the carpet, the glue that holds
the carpet to the floor,
the carpet to the floor,
86
251919
2620
04:26
the paint on the walls, the trees outside.
87
254563
2073
04:28
Everything around you
is producing an odor,
is producing an odor,
88
256660
2417
04:31
and it's a really complex world
that the mosquito has to fly through,
that the mosquito has to fly through,
89
259101
3953
04:35
and it has to find you
within that really complex world.
within that really complex world.
90
263078
4397
04:39
And each and every one of you will know --
91
267499
2032
04:41
Come on, hands up, who always
gets bitten by mosquitoes?
gets bitten by mosquitoes?
92
269555
2626
04:44
And who never gets bitten?
93
272572
1339
04:45
There's always one or two really
annoying people that never get bitten.
annoying people that never get bitten.
94
273935
4166
04:50
But the mosquito
has a really hard job to find you,
has a really hard job to find you,
95
278125
2564
04:52
and that's all to do
with the way you smell.
with the way you smell.
96
280713
2547
04:55
People who don't attract
mosquitoes smell repellent,
mosquitoes smell repellent,
97
283284
3049
04:58
and what we know is that --
98
286357
1580
04:59
(Laughter)
99
287961
1001
05:00
I should clarify, repellent to mosquitoes,
100
288986
3220
05:04
not to people.
101
292230
1151
05:05
(Laughter)
102
293405
1001
05:06
And what we know now
103
294430
1238
05:07
is that that is actually
controlled by our genes.
controlled by our genes.
104
295692
4026
05:11
But mosquitoes are able to do that
105
299742
1642
05:13
because they have
a highly sophisticated sense of smell,
a highly sophisticated sense of smell,
106
301408
2897
05:16
and they're able to see through
all the, sort of, odor sludge
all the, sort of, odor sludge
107
304329
2879
05:19
to find you, that individual,
and bite you as a blood meal.
and bite you as a blood meal.
108
307232
4373
05:24
But what would happen
if one of you was infected with malaria?
if one of you was infected with malaria?
109
312347
4592
05:28
Well, let's just have a quick look
at the malaria life cycle.
at the malaria life cycle.
110
316963
2859
05:31
So it's quite complex,
111
319846
1230
05:33
but basically, what happens is a mosquito
has to bite somebody to become infected.
has to bite somebody to become infected.
112
321100
4047
05:37
Once it bites an infected person,
113
325171
2119
05:39
the parasite travels
through the mouth part into the gut
through the mouth part into the gut
114
327314
3072
05:42
and then bursts
through the gut, creates cysts,
through the gut, creates cysts,
115
330410
2397
05:44
and then the parasites replicate,
116
332831
2451
05:47
and then they make a journey from the gut
all the way to the salivary glands,
all the way to the salivary glands,
117
335306
4111
05:51
where they are then injected
back into another person
back into another person
118
339441
2690
05:54
when the mosquito bites,
because it injects saliva as it bites.
because it injects saliva as it bites.
119
342155
3072
05:57
Then, inside the human,
it goes through a whole other cycle,
it goes through a whole other cycle,
120
345251
2884
06:00
a whole other part of the life cycle,
121
348159
1828
06:02
so it goes through
a liver stage, changes shape,
a liver stage, changes shape,
122
350011
2338
06:04
and then comes out
into the bloodstream again,
into the bloodstream again,
123
352373
2159
06:06
and eventually, that person
will become infectious.
will become infectious.
124
354556
2728
06:09
Now, one thing we know
about the parasite world
about the parasite world
125
357308
2192
06:11
is that they are incredibly good
at manipulating their hosts
at manipulating their hosts
126
359524
3693
06:15
to enhance their own transmission,
127
363241
1633
06:16
to make sure that they get passed onwards.
128
364898
2087
06:19
If this was to happen
in the malaria system,
in the malaria system,
129
367009
2096
06:21
it might make sense
130
369129
1413
06:22
that it would be something
to do with odor that they manipulate,
to do with odor that they manipulate,
131
370566
3215
06:25
because odor is the key.
132
373805
1199
06:27
Odor is the thing that links us
between mosquitoes.
between mosquitoes.
133
375028
2393
06:29
That's how they find us.
134
377445
1586
06:31
This is what we call the malaria
manipulation hypothesis,
manipulation hypothesis,
135
379055
3679
06:34
and it's something that we've been
working on over the last few years.
working on over the last few years.
136
382758
3381
06:39
So one of the first things
that we wanted to do in our study
that we wanted to do in our study
137
387020
3157
06:42
was to find out whether
an infection with malaria
an infection with malaria
138
390201
3459
06:45
actually makes you more attractive
to mosquitoes or not.
to mosquitoes or not.
139
393684
3247
06:48
So in Kenya, with our colleagues,
we designed an experiment
we designed an experiment
140
396955
3135
06:52
where we had participants,
children in Kenya, sleep inside tents.
children in Kenya, sleep inside tents.
141
400114
4254
06:56
The odor from the tent was blown
into a chamber which contained mosquitoes,
into a chamber which contained mosquitoes,
142
404392
3723
07:00
and the mosquitoes would
behaviorally respond.
behaviorally respond.
143
408139
2863
07:03
They would fly towards
or fly away from the odors,
or fly away from the odors,
144
411026
2856
07:05
depending on whether
they liked them or not.
they liked them or not.
145
413906
2331
07:08
Now some of the participants
were infected with malaria,
were infected with malaria,
146
416261
2667
07:10
and some of them were uninfected,
147
418952
1971
07:12
but importantly,
148
420947
1342
07:14
none of the children
had any symptoms whatsoever.
had any symptoms whatsoever.
149
422313
2848
07:18
Now when we found and saw the results,
it was really quite staggering.
it was really quite staggering.
150
426756
3825
07:22
People who were infected with malaria
151
430605
2207
07:24
were significantly more attractive
than people who were uninfected.
than people who were uninfected.
152
432836
3790
07:28
So let me explain this graph.
153
436650
1401
07:30
We have "number of mosquitoes
attracted to the child,"
attracted to the child,"
154
438075
2524
07:32
and we have two sets of data:
before treatment and after treatment.
before treatment and after treatment.
155
440623
3205
07:35
On the far left-hand side,
156
443852
1676
07:37
that bar represents
a group of people who are uninfected,
a group of people who are uninfected,
157
445552
2667
07:40
and as we move
towards the right-hand side,
towards the right-hand side,
158
448243
2050
07:42
these people have become infected
159
450317
1650
07:43
and they're moving towards the stage
that they're infectious.
that they're infectious.
160
451991
2941
07:46
So right at the stage
when people are infectious
when people are infectious
161
454956
2386
07:49
is when they are
significantly more attractive.
significantly more attractive.
162
457366
2478
07:52
In this study, then, what we did
163
460551
1555
07:54
is we obviously gave
the children treatment
the children treatment
164
462130
2222
07:56
to clear the parasites,
165
464376
1193
07:57
and then we tested them again,
166
465593
1888
07:59
and what we found was that highly
attractive trait that was there
attractive trait that was there
167
467505
4087
08:03
disappeared after they had
cleared the infection.
cleared the infection.
168
471616
2366
08:06
So it wasn't just that the people
were more attractive,
were more attractive,
169
474006
2635
08:08
it was that the parasite
was manipulating its host in some way
was manipulating its host in some way
170
476665
3707
08:12
to make it more attractive to mosquitoes,
171
480396
1953
08:14
standing out like a beacon
to attract more mosquitoes
to attract more mosquitoes
172
482373
3309
08:17
so that it could continue its life cycle.
173
485706
2397
08:20
The next thing we wanted to do
was find out what it was
was find out what it was
174
488127
2626
08:22
the mosquito was actually smelling.
175
490777
1736
08:24
What was it detecting?
176
492537
1167
08:25
So to do that, we had to collect
the body odor from the participants,
the body odor from the participants,
177
493728
3548
08:29
and we did this by wrapping
bags around their feet,
bags around their feet,
178
497300
2381
08:31
which allowed us to collect
the volatile odors from their feet,
the volatile odors from their feet,
179
499705
3039
08:34
and feet are really important
to mosquitoes.
to mosquitoes.
180
502768
2048
08:36
They really love the smell of feet.
181
504840
1896
08:38
(Laughter)
182
506760
1015
08:39
Especially cheesy feet.
Anybody got cheesy feet back there?
Anybody got cheesy feet back there?
183
507799
2763
08:42
Mosquitoes love that smell.
184
510586
2029
08:44
So we focused on the feet,
and we collected the body odor.
and we collected the body odor.
185
512639
2777
08:47
Now when it comes to mosquitoes
and olfaction, their sense of smell,
and olfaction, their sense of smell,
186
515440
3667
08:51
it's very complex.
187
519131
1151
08:52
It would be really nice if there was
just one chemical that they detected,
just one chemical that they detected,
188
520306
3477
08:55
but it's not that simple.
189
523807
1363
08:57
They have to detect a number of chemicals
190
525194
2587
08:59
in the right concentration,
the right ratios,
the right ratios,
191
527805
2548
09:02
the right combinations of chemicals.
192
530377
2372
09:05
So you can sort of think about it
like a musical composition.
like a musical composition.
193
533638
3596
09:09
So, you know, if you get the note wrong
or you play it too loud or too soft,
or you play it too loud or too soft,
194
537258
3658
09:12
it doesn't sound right.
195
540940
1159
09:14
Or a recipe: if you get
an ingredient wrong
an ingredient wrong
196
542123
2310
09:16
or you cook it too long or too little,
it doesn't taste right.
it doesn't taste right.
197
544457
3888
09:20
Well, smell is the same.
198
548369
1150
09:21
It's made up of a suite of chemicals
in the right combination.
in the right combination.
199
549543
3866
09:25
Now our machines in the lab
are not particularly good
are not particularly good
200
553433
2626
09:28
at picking out this sort of signal --
it's quite complex.
it's quite complex.
201
556083
3191
09:31
But animals can,
and what we do in my laboratory
and what we do in my laboratory
202
559298
3737
09:35
is we connect microelectrodes
to the antennae of a mosquito.
to the antennae of a mosquito.
203
563059
5096
09:40
Imagine how fiddly that is.
204
568179
1523
09:41
(Laughter)
205
569726
1555
09:43
But what we also do is connect them
to individual cells within the antennae,
to individual cells within the antennae,
206
571305
4032
09:47
which is incredible.
207
575361
1151
09:48
You don't want to sneeze
when you're doing this,
when you're doing this,
208
576536
2298
09:50
that's for sure.
209
578858
1466
09:52
But what this does is it allows us
210
580348
1643
09:54
to measure the electrical response
of the smell receptors in the antennae,
of the smell receptors in the antennae,
211
582015
3563
09:57
and so we can see
what a mosquito is smelling.
what a mosquito is smelling.
212
585602
3349
10:00
So I'm going to show you
what this looks like.
what this looks like.
213
588975
2143
10:03
Here's an insect's cell,
214
591142
1151
10:04
and it will respond in a second
when I press this button,
when I press this button,
215
592317
2952
10:07
and you'll see it sort of taking over
with this response.
with this response.
216
595293
2734
10:10
An odor will be blown over the cell,
217
598051
1801
10:11
and it will go a bit crazy,
sort of blow a raspberry,
sort of blow a raspberry,
218
599876
2539
10:14
and then it will go back to its resting
potential when we stop the odor.
potential when we stop the odor.
219
602439
3414
10:17
(Rapid crackling)
220
605877
6983
10:24
(Low-pitch crackling)
221
612884
6095
10:31
(Rapid crackling)
222
619003
6529
10:37
OK, there we go,
223
625556
1151
10:38
so you can go home now and say
that you've seen an insect smelling
that you've seen an insect smelling
224
626731
3781
10:42
and even hearing an insect smelling --
it's a weird concept, isn't it?
it's a weird concept, isn't it?
225
630536
3344
10:45
But this works really well,
226
633904
1379
10:47
and this allows us to see
what the insect is detecting.
what the insect is detecting.
227
635307
2658
10:49
Now using this method
with our malaria samples,
with our malaria samples,
228
637989
2582
10:52
we were able to find out
what the mosquito was detecting,
what the mosquito was detecting,
229
640595
3196
10:55
and we found the malaria-associated
compounds, mainly aldehydes,
compounds, mainly aldehydes,
230
643815
3593
10:59
a group of compounds that smelled,
that signified the malaria signal here.
that signified the malaria signal here.
231
647432
4662
11:04
So now we know
what the smell of malaria is,
what the smell of malaria is,
232
652118
2122
11:06
and we've used the mosquito as a biosensor
233
654264
2753
11:09
to tell us what the smell
of malaria actually is.
of malaria actually is.
234
657041
3810
11:13
Now I'd like to imagine
235
661455
1469
11:14
that you could, I don't know,
put a harness on a little mosquito
put a harness on a little mosquito
236
662948
3580
11:18
and put it on a lead and take it out
and see if we can sniff people
and see if we can sniff people
237
666552
4737
11:23
in a community --
238
671313
1422
11:24
that goes on in my head --
239
672759
2023
11:26
and see whether we could
actually find people with malaria,
actually find people with malaria,
240
674806
2762
11:29
but, of course,
that's not really possible.
that's not really possible.
241
677592
2563
11:33
But there is an animal
that we can do that with.
that we can do that with.
242
681141
3151
11:36
Now dogs have an incredible
sense of smell,
sense of smell,
243
684316
2399
11:38
but there's something
more special about them:
more special about them:
244
686739
2204
11:40
they have an ability to learn.
245
688967
1941
11:42
And most of you people will be
familiar with this concept at airports,
familiar with this concept at airports,
246
690932
3286
11:46
where dogs will go down a line
and sniff out your luggage or yourself
and sniff out your luggage or yourself
247
694242
3627
11:49
for drugs and explosives
or even food as well.
or even food as well.
248
697893
3601
11:53
So we wanted to know,
could we actually train dogs
could we actually train dogs
249
701518
2696
11:56
to learn the smell of malaria?
250
704238
2698
11:59
And so we've been working with a charity
called Medical Detection Dogs
called Medical Detection Dogs
251
707720
3732
12:04
to see whether we can train them
to learn the smell of malaria.
to learn the smell of malaria.
252
712301
3778
12:08
And we went out to the Gambia
and did some more odor collection
and did some more odor collection
253
716103
2991
12:11
on children that were infected
and uninfected,
and uninfected,
254
719118
2302
12:13
but this time, we collected their odor
255
721444
2119
12:15
by making them wear socks,
nylon stockings,
nylon stockings,
256
723587
3124
12:18
to collect their body odor.
257
726735
1507
12:20
And we brought them back to the UK
258
728266
1747
12:22
and then we handed them to this charity
to run the experiment.
to run the experiment.
259
730037
3702
12:27
Now I could show you a graph
and tell you about that experiment works,
and tell you about that experiment works,
260
735242
3934
12:31
but that'd be a bit dull, wouldn't it.
261
739200
2047
12:34
Now, they do say never work
with children or animals live,
with children or animals live,
262
742918
5611
12:40
but we're going to break that rule today.
263
748553
2218
12:42
So please welcome onto the stage Freya ...
264
750795
4024
12:46
(Applause)
265
754843
2079
12:48
and her trainers Mark and Sarah.
266
756946
4764
12:53
(Applause)
267
761734
3185
12:56
Of course, this is
the real star of the show.
the real star of the show.
268
764943
2128
12:59
(Laughter)
269
767095
1057
13:00
OK, so now what I'm going to ask is
if you can all just be a little bit quiet,
if you can all just be a little bit quiet,
270
768176
5245
13:05
not move around too much.
271
773445
1221
13:06
This is a very, very strange
environment for Freya.
environment for Freya.
272
774690
2381
13:09
She's having a good look at you guys now.
273
777095
2135
13:11
So let's stay as calm as possible.
That would be great.
That would be great.
274
779254
2793
13:14
So what we're going to do here
is basically, we're going to ask Freya
is basically, we're going to ask Freya
275
782961
3239
13:18
to move down this line
of contraptions here,
of contraptions here,
276
786224
2072
13:20
and in each one of these
contraptions, we have a pot,
contraptions, we have a pot,
277
788320
2635
13:22
and in the pot is a sock that has been
worn by a child in the Gambia.
worn by a child in the Gambia.
278
790979
3818
13:26
Now three of the socks have been worn
by children who were uninfected,
by children who were uninfected,
279
794821
3739
13:30
and just one of the socks was worn
by a child who was infected with malaria.
by a child who was infected with malaria.
280
798584
4745
13:35
So just as you would see an airport,
imagine these were people,
imagine these were people,
281
803353
2956
13:38
and the dog is going to go down
and have a good sniff.
and have a good sniff.
282
806323
2538
13:40
And let's see if you can see
when she senses the malaria,
when she senses the malaria,
283
808885
3921
13:44
and if she senses the malaria.
284
812830
1430
13:46
This is a really tough test for her
in this very strange environment,
in this very strange environment,
285
814284
3309
13:49
so I'm going to hand it over now to Mark.
286
817617
2126
14:08
(Laughs) Number three. OK.
287
836339
2394
14:10
(Applause)
288
838757
1029
14:11
There we go.
289
839810
1152
14:12
I didn't know which pot that was in.
Mark didn't know.
Mark didn't know.
290
840986
2829
14:15
This was a blind test, genuinely.
Sarah, was that correct?
Sarah, was that correct?
291
843839
3148
14:19
Sarah: Yes.
292
847011
1166
14:20
JL: That was correct. Well done, Freya.
That is fantastic. Whew.
That is fantastic. Whew.
293
848201
3459
14:23
(Applause)
294
851684
2566
14:26
That is really wonderful.
295
854274
2150
14:28
Now Sarah is going to actually change
the pots around a little bit,
the pots around a little bit,
296
856448
3163
14:31
and she's going to take
the one with malaria away,
the one with malaria away,
297
859635
2386
14:34
and we're just going to have four pots
that are containing socks from children
that are containing socks from children
298
862045
4718
14:38
that had no malaria,
299
866787
1212
14:40
so in theory, Freya should go
down the line and not stop at all.
down the line and not stop at all.
300
868023
3215
14:43
And this is really important,
301
871262
1464
14:44
because we also need to know
people who are not infected,
people who are not infected,
302
872750
2795
14:47
she needs to be able to do that.
303
875569
1525
14:49
And this is a tough test.
304
877118
1224
14:50
These socks have been in the freezer
for a couple of years now,
for a couple of years now,
305
878366
3182
14:53
and this is a tiny bit of a sock as well.
306
881572
2820
14:56
So imagine if this was a whole person,
giving off a big signal.
giving off a big signal.
307
884416
3098
14:59
So this is really incredible.
308
887538
1405
15:00
OK, over to you, Mark.
309
888967
1458
15:09
(Laughs)
310
897538
1151
15:10
(Applause)
311
898713
1001
15:11
Brilliant. Fantastic.
312
899738
2538
15:14
(Applause)
313
902300
2403
15:16
Really super. Thank you so much, guys.
314
904727
1906
15:18
Big round of applause
for Freya, Mark and Sarah.
for Freya, Mark and Sarah.
315
906657
2652
15:21
Well done, guys.
316
909333
1158
15:22
(Applause)
317
910515
2874
15:25
What a good girl.
She's going to get a treat later.
She's going to get a treat later.
318
913413
3222
15:28
Fantastic.
319
916659
1176
15:31
So you've just seen that
for your own eyes.
for your own eyes.
320
919079
2039
15:33
That was a real live demonstration.
I was quite nervous about it.
I was quite nervous about it.
321
921142
3048
15:36
I'm so glad that it worked.
322
924214
1372
15:37
(Laughter)
323
925610
1563
15:39
But it is really incredible,
and when we do this,
and when we do this,
324
927731
2604
15:42
what we find is that these dogs
can correctly tell us
can correctly tell us
325
930359
3076
15:45
when somebody is infected with malaria
81 percent of the time.
81 percent of the time.
326
933459
3239
15:48
It's incredible.
327
936722
1171
15:49
92 percent of the time,
328
937917
1287
15:51
they can tell us correctly
when somebody does not have an infection.
when somebody does not have an infection.
329
939228
3325
15:54
And those numbers
are actually above the criteria
are actually above the criteria
330
942577
2810
15:57
set by the World Health Organization
for a diagnostic.
for a diagnostic.
331
945411
3730
16:01
So we really are looking
at deploying dogs in countries,
at deploying dogs in countries,
332
949165
3765
16:04
and particularly at ports of entry,
333
952954
1995
16:06
to detect people who have malaria.
334
954973
2633
16:09
This could be a reality.
335
957630
2125
16:12
But we can't deploy dogs everywhere,
336
960603
2150
16:14
and so what we're also looking to do
and working on at the moment
and working on at the moment
337
962777
3652
16:18
is the development of technology,
338
966453
2277
16:20
wearable tech that would
empower the individual
empower the individual
339
968754
3175
16:23
to allow them to self-diagnose.
340
971953
2742
16:26
Imagine a patch that you wear on the skin
341
974719
2542
16:29
that would detect in your sweat
when you're infected with malaria
when you're infected with malaria
342
977285
3244
16:32
and change color.
343
980553
1223
16:33
Or something a little more
technical, perhaps:
technical, perhaps:
344
981800
2253
16:36
a smartwatch that would alert you
when you're infected with malaria.
when you're infected with malaria.
345
984077
4235
16:40
And if we can do this digitally,
and we can collect data,
and we can collect data,
346
988336
3389
16:43
imagine the amount of data
that we can collect on a global scale.
that we can collect on a global scale.
347
991749
5058
16:48
This could completely revolutionize
348
996831
1736
16:50
the way that we track
the spread of diseases,
the spread of diseases,
349
998591
2223
16:52
the way that we target our control efforts
and respond to disease outbreaks,
and respond to disease outbreaks,
350
1000838
4468
16:57
ultimately helping to lead
to the eradication of malaria,
to the eradication of malaria,
351
1005330
3917
17:01
and even beyond malaria,
352
1009271
1377
17:02
for other diseases
that we already know have a smell.
that we already know have a smell.
353
1010672
3011
17:05
If we can harness the power of nature
to find out what those smells are,
to find out what those smells are,
354
1013707
3437
17:09
we could do this and make this a reality.
355
1017168
2443
17:12
Now, as scientists, we're tasked
with coming up with new ideas,
with coming up with new ideas,
356
1020945
4766
17:17
new concepts, new technologies
357
1025735
2408
17:20
to tackle some of the world's
greatest problems,
greatest problems,
358
1028167
4115
17:24
but what never ceases to amaze me
359
1032306
2048
17:26
is that often nature
has already done this for us,
has already done this for us,
360
1034378
4245
17:30
and the answer ...
361
1038647
1249
17:32
is right under our nose.
362
1040436
1778
17:35
Thank you.
363
1043314
1151
17:36
(Applause)
364
1044489
2582
ABOUT THE SPEAKER
James Logan - Biologist, medical entomologistProfessor James Logan leads an internationally renowned research program at the London School of Hygiene and Tropical Medicine, presents television programs and has a passion for science and natural history.
Why you should listen
Professor James Logan's research group explores the complex interaction between arthropod vectors, and his groundbreaking research has led to the discovery of novel methods for the control of vectors that transmit pathogens that cause diseases such as malaria, Zika, dengue, trachoma and Lyme disease. His work extends into field evaluation of vector control tools in developing countries, and his recent research discovered that malaria infection causes changes in our body odor, making us more attractive to mosquitoes. He's now working on translating that to develop a novel, non-invasive diagnostic for malaria.
Logan is a Fellow of the Royal Entomological Society and has a first-class BSc honours degree in Zoology from the University of Aberdeen and an award-winning PhD, which he completed in 2005. He is also an entrepreneur, having spun out two companies from his University, and holds the position of Director and Founder of ARCTEC and Director and Founder of Vecotech Ltd. Logan regularly advises UK government departments on aspects of vector biology, invasive species and vector control.
James Logan | Speaker | TED.com