Yes. Botrytis blight is a gray fungal infection that usually attacks hydrangea flower buds and petals. You control it by applying imidazole fungicides containing Iprodione.

Some hydrangeas will temporarily have some reddish color on the leaves in a similar way a new growth on roses turns reddish. This fades on its own in a few days and is caused by weather conditions. Can you post a picture?

The plant is doing better now, I see a lot of green leaves and I have trimmed away most of the red leaves. I thought they were new growth leaves, but they stay red. If all the leaves are red, the plant won't have chlorophyll.

Here is a link that might be useful: photo of plant with red leaves

That's not botrytis on your plant, and,

"Colored leaves have chlorophyll too"

Here is a link that might be useful: Svenson, OSU

The above article refers to plants that are supposed to have colored leaves, not green leaf plants that turn red, and those red leaves had curling of them on the edges. I don't know why the leaves turned red, but I had it on another hydrangea also. But, anyway it almost cured, so I wanted to leave a tip for anyone else who has this problem, as there is no information about red leaves on hydrangeas.