My name is Kathleen McLaughlin. I am a journalist and right now I'm also a patient. I have an infusion every few weeks of a drug that's made from human blood. I'm having one right now, which is why you might hear these beeps in the background. It's the steady noise of an infusion pump, which pushes the drug, human immunoglobin,

into a vein on the back of my right hand.

I'm sitting in a red recliner with my feet up.

It's all very comfortable, apart from the fact that I'll be in this chair all day,

working, writing, watching a little television, but I'm tied to a plastic infusion bag

full of medication. I have a rare, sometimes disabling autoimmune disorder. Without this treatment,

my arms and legs slowly go numb and eventually cease to work in any predictable way. With it, I'm fine.

I lead an active life, and that's all thanks to other people's blood. I've spent many days like this

in the past 20 years. I've often thought about all the thousands of people who donate the plasma from which my drug

is made. And that's how I began reporting on the global trade in human blood.

This is America, the Human Plasma Factory, for the documentary from the BBC World Service.

There are over a thousand commercial plasma donation centers in the USA.

There's one just a few blocks from where I'm sitting.

And you can find donation centers all over my home state of Montana.

How often do you donate plasma?

Twice a week. Is it worth the money for you?

To me, yes.

It helps me get to a little bits at a time.

It gets me by until I do it again.

How long do you think you'll be doing this for?

Probably until I can anymore, to be honest.

I hope my plasma can help someone else, but that's, you know, my hopes.

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