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

含有石的水滴落石床形成石笋。

First, there's a reduction in gray matter.

第一，大的减少。

Polio mainly affects children under 5 years of age.

脊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，主要负责人们的数学技能。

They were used to help create polio vaccine.

它们被用来帮助制造脊炎疫苗。

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

脊由和白共同组成。

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

检测到的病毒株不是野生脊炎病毒，而是一种被称为2型疫苗衍生脊炎病毒的病毒株。

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

目标是结束野生脊炎病毒的传播。

It is similar to how polio vaccines are made.

这与脊炎疫苗的制造方法相似。

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

常见的疫苗有脊炎疫苗和天花疫苗。

Does it really protect against polio?

它真的能预防脊炎吗？

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

脊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·阿穆尔在两岁的时候患了脊炎。

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炎病例。

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炎。

Jonas Salk and the polio vaccine.

乔纳斯·索尔克和脊炎疫苗。

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

脊炎病毒在这些社区是非常无情的，你知道。

By 2030 it will be gone.

到2030年，脊炎就会消失。

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

减少的同时，白正在增加。