devastating pandemics in human history.

人類歷史上毀滅性的大流行病。

Between 1347 and 1351, it wiped out 30% to 50%

1347年到1351年之間，它消滅了30%到50%的人。

of the entire population of Europe.

佔歐洲總人口的。

And if there's one animal to blame,

如果有一個動物要責怪。

it's likely infected fleas,

很可能是感染了跳蚤。

making them one of the deadliest insects in history.

使它們成為歷史上最致命的昆蟲之一。

Now, of course, fleas no longer kill millions of people.

當然，現在，跳蚤已經不再殺死數百萬人。

But as it turns out, they still transmit plague,

但事實證明，他們還是會傳播瘟疫。

they're still a nuisance,

他們仍然是一個麻煩。

and they're still incredibly difficult to kill.

而且他們還非常難殺。

Fleas are one of the oldest pests on the planet.

跳蚤是地球上最古老的害蟲之一。

In fact, primitive fleas were dining on dinosaur blood

事實上，原始的跳蚤是以恐龍血為食的

about 165 million years ago.

約1.65億年前。

And they're also one of the most abundant.

而且它們也是最豐富的一種。

Today, there are more than 2,500 species

今天，有超過2,500個物種。

of fleas across the world, like the cat flea.

的跳蚤，比如貓跳蚤。

Those are the ones you're most likely to find

這些是你最有可能找到的。

feasting on your dog or your cat.

宴請你的狗或貓。

And then there are species like the human flea,

還有像人類跳蚤這樣的物種。

which actually seek out human hosts specifically.

實際上是專門尋找人類宿主的。

And seeking is a flea's specialty.

而尋找是跳蚤的專長。

They can sense your breath, your warmth,

他們能感覺到你的呼吸，你的溫暖。

and even the vibrations of your feet.

甚至是腳的震動。

And when they find you, they do what fleas do best:

當它們找到你的時候，它們會做跳蚤最擅長的事情。

jump.

跳。

According to one study, some fleas can jump

根據一項研究，一些跳蚤可以跳到。

nearly 100 times farther than the length of their body,

比其身體長度遠近100倍。

which would be like an average man

儼然是一個普通人

jumping nearly 175 meters into the air.

跳到近175米的高空。

The secret to their spring is a stretchy protein

他們的春天的祕密是一種彈性蛋白。

in their legs called resilin,

在他們的腿上被稱為resilin。

and it works like a rubber band in a slingshot.

它的工作原理就像彈弓裡的橡皮筋。

Elizabeth Warburton: They have kind of a hook-and-latch

伊麗莎白-沃伯頓They have kind of a hook -and -latch.

type of system.

型的系統。

And when the flea lets go of the latch, they just jump.

當跳蚤放開門閂的時候，它們就會跳下去。

Narrator: Now, that makes fleas difficult to capture

旁白：這使得跳蚤難以捕捉

and kill, but it's what they do once they land

但這是他們落地後要做的事。

that makes them a truly terrifying pest.

這讓他們成為真正可怕的害蟲。

First, they use blades in their mouth

首先，他們用嘴裡的刀片

called maxillary laciniae to tear into your flesh.

稱為上頜裂紋，以撕裂你的肉體。

Then they use a straw-like structure

然後他們用稻草一樣的結構

called an epipharynx to slurp it all up.

稱為上咽部，將其全部嚥下。

It's not unlike...

這並不像...

Warburton: If you spilled your drink on a table

沃伯頓If you spilled your drink on a table

and you took a straw and you tried to drink it up.

你拿著吸管想把它喝光。

[slurping]

[嘖嘖]

Narrator: Yum.

旁白：百勝。

Adding insult to injury, fleas have proteins

雪上加霜的是，跳蚤有蛋白質。

in their saliva that keep your blood flowing

在他們的唾液中，保持你的血液流動。

so they have a constant supply of food.

所以他們有一個穩定的食物供應。

And that's actually why they itch so much.

而這其實也是他們為什麼這麼癢的原因。

Your body (or your pet's) is reacting to those proteins.

你的身體（或寵物的身體）正在對這些蛋白質產生反應。

But there's one flea that takes feeding

但有一隻跳蚤需要餵食。

to another, more horrifying level.

到另一個，更可怕的水準。

And, unfortunately, it prefers to prey on humans:

而且，不幸的是，它更喜歡捕食人類。

Tunga penetrans, aka the chigoe flea.

Tunga penetrans，又名chigoe跳蚤。

Instead of drinking blood from the surface of your skin,

而不是從皮膚表面喝血。

the females burrow into you,

雌性鑽進你的身體。

and then they start laying eggs.

然後他們開始下蛋。

Warburton: Most of her is buried into the skin,

沃伯頓。她的大部分都被埋進了皮膚裡。

but kind of the back part, where she's releasing eggs,

但後面的部分，她在那裡釋放雞蛋。

is exposed.

是暴露。

Narrator: And fleas lay a lot of eggs.

旁白：而且跳蚤會產很多卵

Up to 40 each day and as many as 2,000 in their lifetimes.

每天多達40人，一生中多達2000人。

So if your dog brings back a few fleas from the park,

所以如果你的狗從公園帶回來幾隻跳蚤。

you could soon have thousands.

你很快就會有成千上萬的人。

And the truth is they can do a lot worse than make you itch.

而事實是，他們能做的比讓你發癢更糟糕。

You see, even modern fleas can transfer diseases

你看，即使是現代的跳蚤也會傳染疾病。

like typhus, bartonellosis, and, yes, plague.

比如斑疹傷寒，巴氏桿菌病，還有，是的，瘟疫。

In fact, in the summer of 2019,

事實上，在2019年夏天。

the discovery of prairie dogs infected

感染草原犬的發現

by plague-ridden fleas shut down parts of a Denver suburb.

由瘟疫肆虐的跳蚤關閉了丹佛郊區的部分地區。

And in 2015, a teen reportedly died

而在2015年，據報道，一名少年死

from contact with fleas infected with bubonic plague.

因接觸感染鼠疫的跳蚤而引起的。

Now, fortunately, fatal fleas are pretty rare,

現在，幸運的是，致命的跳蚤非常罕見。

and most likely it'll be your pets, not you,

而且很可能是你的寵物，而不是你。

that have to deal with them.

必須與他們打交道的。

But if you do see one or two jumping around,

但如果你真的看到一兩個跳來跳去。

you definitely should try to get rid of them.

你一定要設法擺脫他們。

And here's how.

而這裡的方法。

First, identify the source. And if it's your pet,

首先，確定源頭。如果是你的寵物。

treat them with an insect growth regulator, like Lufenuron.

用昆蟲生長調節劑處理它們，如Lufenuron。

Next, clean your home, though you might want to steer clear

接下來，清潔你的家，雖然你可能想避開

of flea bombs or foggers; they're inconvenient

跳蚤炸彈或霧化器，它們是不方便的。

and don't always reach the nooks and crannies

不見得就能摸到旮旯裡去

where fleas are hanging out.

跳蚤出沒的地方。

Instead, repeatedly vacuum or mop your floors

反之，反覆吸塵或拖地。

and toss any bedding into the washing machine,

並將任何被褥扔進洗衣機。

making sure to dry it at high heat.

一定要用高溫烘乾。

After that, all you can do is sit, wait,

之後，你能做的就是坐著，等著。

and hope that you're flea-free.

並希望你沒有跳蚤。