I have two peach trees in my garden. One was a purchase, a present that was going to be an apricot tree. The other grew from out of the compost heap. Neither of these trees have yet produced any peaches. Both have had red swellings that have formed on the leaves. I had seen red lumps on willow trees as a child so decided to try and find out what had caused them and how I could get rid of them.
The problem however, was taken out of my hands as my husband merrily sprayed the branches with bug spray, left the branches for a week or so and cut off the worst of the problem. This cured both the trees. So when I began to investigate and came across websites stating that the disease taphrina deformans is caused through a fungal infection I think that they may well be quite wrong. I would say it is more likely to be caused through an infection possibly a virus spread by a microscopic mite such as a similar attacks on willow leaves.
Infected peach leaves with Taphrina deformans
Thankfully both my peach trees are now beautiful with no signs of the red lumps that you see above.