Hi Pv Picotte,

Those plants don't look a lot like my zinnia plants. Your zinnias appear to be significantly taller than my zinnias, and almost all of my zinnias have green stems. Those foliage spots are kind of purple colored like the stems. I have grown a lot of zinnias and I have seen bacterial and fungal leaf spot diseases, but nothing that looks like your photo. Just out of curiosity, what variety are those zinnias?

As for the grasshoppers, I think they could spread a foliage disease with their feet, just by walking around.

ZM