James Logan: How we're using dogs to sniff out malaria
詹姆士‧洛根: 我們如何靠狗嗅出瘧疾
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
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killers on the planet.
我們已有重大的進展
in the last 20 years,
is still at risk from this disease.
仍然在瘧疾的威脅之中
dies from malaria.
when it comes to tackling malaria,
也面臨到許多挑戰
infected with malaria in the first place.
some level of immunity to the disease,
有一定程度的免疫力
and become infectious and still pass it on
因為要找到這些帶原者
because how do you find those people?
for a needle in a haystack.
to solve this problem for some years,
may have been right under our noses
或許早已在我們的眼前
with lots of really important statistics,
to just relax a little bit
a little bit as well.
a nice deep breath in ...
just through your nose,
the environment around you.
the person who's sitting next to you.
坐在你隔壁的那個人
靠近對方的腋下
right into their armpit,
have a good old sniff,
sensory experience there.
something rather pleasant,
something a little bit less pleasant,
bad breath or body odor.
a good reason
don't like certain body smells.
不喜歡特定的體味
being associated with a smell.
疾病與氣味的關聯
就像是烤焦的麵包
smells like baked brown bread,
像是生肉一樣的味道
of a butcher shop, like raw meat.
這類形容疾病的字詞
at the sort of words that are used
gets a bit of bad reputation.
not exactly as a compliment, are you.
to turn that on its head.
think about smell in a positive way,
看待這些氣味呢?
身體所散發出的化學物質
by our bodies when we're ill,
that would allow us to do this,
讓我們能夠做到這一點
best sensors actually already exist,
其實已經存在了
according to their nose.
really important information
and you've entered this room.
a really complex world.
with smells from everywhere.
that we're really smelly beasts.
different volatile chemicals.
不同的揮發性化學物質
而是相當相當多的化學物質
it's the seats you're sitting on,
the carpet to the floor,
is producing an odor,
that the mosquito has to fly through,
這個相當複雜的世界
within that really complex world.
相當複雜的世界中找到你
gets bitten by mosquitoes?
annoying people that never get bitten.
has a really hard job to find you,
with the way you smell.
就不會吸引到蚊子
mosquitoes smell repellent,
氣味是由我們的基因所控制
controlled by our genes.
a highly sophisticated sense of smell,
all the, sort of, odor sludge
吸你的血飽餐一頓
and bite you as a blood meal.
if one of you was infected with malaria?
會發生什麼事情呢?
at the malaria life cycle.
has to bite somebody to become infected.
一隻蚊子叮咬某人後被感染
through the mouth part into the gut
through the gut, creates cysts,
all the way to the salivary glands,
back into another person
被注射到另一個人的身體
because it injects saliva as it bites.
會將唾液注射到人的身體中
it goes through a whole other cycle,
寄生蟲會歷經另一個週期
a liver stage, changes shape,
into the bloodstream again,
will become infectious.
about the parasite world
at manipulating their hosts
或許能夠說得通一件事情
in the malaria system,
to do with odor that they manipulate,
between mosquitoes.
manipulation hypothesis,
working on over the last few years.
that we wanted to do in our study
an infection with malaria
to mosquitoes or not.
we designed an experiment
children in Kenya, sleep inside tents.
into a chamber which contained mosquitoes,
behaviorally respond.
or fly away from the odors,
they liked them or not.
were infected with malaria,
had any symptoms whatsoever.
it was really quite staggering.
than people who were uninfected.
attracted to the child,"
分別為治療前與治療後
before treatment and after treatment.
a group of people who are uninfected,
這些代表已感染的人
towards the right-hand side,
that they're infectious.
when people are infectious
significantly more attractive.
the children treatment
然後再一次以他們做測試
attractive trait that was there
cleared the infection.
were more attractive,
was manipulating its host in some way
to attract more mosquitoes
was find out what it was
我們必須搜集參與者的體味
the body odor from the participants,
bags around their feet,
the volatile odors from their feet,
to mosquitoes.
Anybody got cheesy feet back there?
搜集這些體味
and we collected the body odor.
and olfaction, their sense of smell,
just one chemical that they detected,
那事情就容易多了
濃度正確的化學物質
the right ratios,
like a musical composition.
或是彈奏得太大聲或太柔和
or you play it too loud or too soft,
an ingredient wrong
it doesn't taste right.
味道嘗起來就不太對勁
in the right combination.
are not particularly good
這事情相當的複雜
it's quite complex.
and what we do in my laboratory
to the antennae of a mosquito.
to individual cells within the antennae,
絕對不想打噴嚏
when you're doing this,
of the smell receptors in the antennae,
蚊子聞到了什麼
what a mosquito is smelling.
what this looks like.
這是昆蟲的細胞
when I press this button,
with this response.
sort of blow a raspberry,
它會發出一串呸呸聲
potential when we stop the odor.
它會恢復到靜止電位
你看到昆蟲在聞東西
that you've seen an insect smelling
it's a weird concept, isn't it?
what the insect is detecting.
with our malaria samples,
運用在瘧疾的樣本上
what the mosquito was detecting,
compounds, mainly aldehydes,
也就是瘧疾的訊號
that signified the malaria signal here.
what the smell of malaria is,
of malaria actually is.
實際上聞起來的味道
put a harness on a little mosquito
and see if we can sniff people
actually find people with malaria,
that's not really possible.
協助我們做到這件事
that we can do that with.
sense of smell,
more special about them:
familiar with this concept at airports,
對這個概念相當熟悉
嗅一下你或是你的行李
and sniff out your luggage or yourself
or even food as well.
could we actually train dogs
能否訓練這些狗聞出瘧疾的味道?
called Medical Detection Dogs
(Medical Detection Dogs)
讓狗聞出瘧疾的味道
to learn the smell of malaria.
and did some more odor collection
and uninfected,
nylon stockings,
to run the experiment.
and tell you about that experiment works,
with children or animals live,
別讓孩子和動物在現場示範
the real star of the show.
if you can all just be a little bit quiet,
environment for Freya.
這樣會比較好
That would be great.
is basically, we're going to ask Freya
of contraptions here,
contraptions, we have a pot,
worn by a child in the Gambia.
是未感染孩童穿過的
by children who were uninfected,
是感染瘧疾的孩童穿過的
by a child who was infected with malaria.
想像這些襪子就是人群
imagine these were people,
and have a good sniff.
when she senses the malaria,
對狗來說是一項艱鉅的任務
in this very strange environment,
Mark didn't know.
Sarah, was that correct?
That is fantastic. Whew.
the pots around a little bit,
the one with malaria away,
that are containing socks from children
down the line and not stop at all.
people who are not infected,
for a couple of years now,
它們正散發出重要的訊息
giving off a big signal.
for Freya, Mark and Sarah.
一個熱烈的掌聲!
She's going to get a treat later.
for your own eyes.
I was quite nervous about it.
and when we do this,
而且當我們執行時
can correctly tell us
81 percent of the time.
when somebody does not have an infection.
are actually above the criteria
for a diagnostic.
at deploying dogs in countries,
將狗部署在一些國家
and working on at the moment
empower the individual
when you're infected with malaria
貼片的顏色就會改變
technical, perhaps:
會警示你的一款智慧手錶
when you're infected with malaria.
and we can collect data,
那麼就可以搜集數據
我們可以搜集到全球的數據
that we can collect on a global scale.
the spread of diseases,
以及應對疾病爆發的方式
and respond to disease outbreaks,
to the eradication of malaria,
that we already know have a smell.
to find out what those smells are,
去發現那些氣味是什麼
with coming up with new ideas,
greatest problems,
has already done this for us,
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