Stalagmites grow up where lime laid and drips hit the cave floor.

含有石灰质水滴落石床形成石笋。

First, there's a reduction in gray matter.

第一，大脑灰质减少。

Polio mainly affects children under 5 years of age.

脊灰质炎主要影响五岁以下儿童。

And we know that gray matter is more responsible for people's math skills.

我们知道，灰质主要负责人们技能。

They were used to help create polio vaccine.

它们被用来帮助制造脊灰质炎疫苗。

Now, the spinal cord is composed of both grey and white matter.

脊由灰质和白质共同组成。

The strain detected isn't wild poliovirus, but a strain known as vaccine-derived poliovirus type 2.

检测到株不是野生脊灰质炎，而是一种被称为2型疫苗衍生脊灰质炎株。

The goal is to end transmission of the wild polio virus.

目标是结束野生脊灰质炎传播。

It is similar to how polio vaccines are made.

这与脊灰质炎疫苗制造方法相似。

Common vaccines are the polio vaccine and the small pox vaccine.

常见疫苗有脊灰质炎疫苗和天花疫苗。

Does it really protect against polio?

它真能预防脊灰质炎吗？

Polio mainly affects children under five years of age. The virus is passed through food or water.

脊灰质炎主要影响五岁以下儿童。

The Salk polio vaccine is a success. The vaccine works.

索尔克脊灰质炎疫苗取得了成功。疫苗起作用了。

James Amule got polio when he was two years old.

詹姆斯·阿穆尔在两岁时候患了脊灰质炎。

In neighboring India, no polio cases have been reported for the past three years.

在邻国印度，过去三年没有报道出现脊灰质炎例。

Polio has been detected among several children in the area.

在该地区在一些孩子身上已经诊断出脊灰质炎。

Jonas Salk and the polio vaccine.

乔纳斯·索尔克和脊灰质炎疫苗。

Polio virus is very unforgiving in these communities, you know.

脊灰质炎在这些社区是非常无情，你知道。

By 2030 it will be gone.

到2030年，脊灰质炎就会消失。

This gray matter reduction coincides with an increase in white matter.

灰质减少同时，白质正在增加。