Howdy, Ali :😎
I dont know of any ivy diseases.
It could be a issue of a spot, area, not getting enough water, or no water.
Also possible : A major root, or cane got cut while pruning, or digging.
Most suspect area, is, to the right, bottom side of fence. Check and see if that plant is alive.
Then trim all the dead parts off, it will fill in. Help it along by training the vines into dead/bare areas. 👍
If, one plant is dead.
Take 3 or 4, 6 to 8 inch vine tips, and bury them half way in ground, keep them watered, they'll root, and leave
them all grow. 👍
Also : Ivy like quite a bit of water.