NICK SCHIFRIN: Finally tonight, the lengths and heights one nurse goes for her patients.

Here's John Yang.

JOHN YANG (voice-over): To reach the isolated eastern Uganda mountain communities that need her help, nurse Agnes Namboza scales a treacherous 1,000 foot ladder.

It's too steep for small children, mothers carrying babies and the sick to climb down.

AGNES NAMBOZO, Health Worker: Pregnant mothers, we can -- when we come, we also assess them because the journey is long to the health facilities, the HIV patients, they are those who are bedridden and those with TB.

They are unable to come and pick the drugs at the health facilities.

So sometimes we bring for them the treatment to their homes.

JOHN YANG (voice-over): Her most essential mission is vaccinating children against polio, measles, tetanus and pneumonia as Uganda pushes to reduce the high rate of childhood mortality.

RUTH WANYENZE, Resident of Bulambuli, Uganda: Before she came, we used to walk down there up to Zema.

Sometimes we didn't finish even immunization of our children because the journey is so long.

As she comes, she has helped us so much climbing this area and we are now finishing immunizing our children.

JOHN YANG (voice-over): The Gates Foundation has recognized her work, which doesn't stop for rain.

And now Nambozo's path has gotten tougher.

USAID cuts have eliminated many jobs at her clinic.

As she and those who remain try to take up the slack, avoiding burnout could be as much of a challenge as getting to the isolated communities that need her help.