Answer: The symptoms of leaf blight on camellia don't match what you've described. Generally, the cells of the leaves are attacked and the disease spreads rapidly, causing the leaves to blacken and die. Yellowing of leaves and accompanying brown spots sounds more like a combination of oedema (if the spots are brown and corky), chlorosis (a deficiency of elements in the soil), scale insects, and/or a fungal spot disease.
It's important to have a positive diagnosis before treating the problem(s). Your local Cooperative Extension service can provide expert advice on the problem. (Phone 601-328-8619).
You might want to make sure you're providing everything your camellia needs in terms of sunshine/shade, food and water. Plants that are under stress seem to develop more insect and disease problems.
Hope your camellia recovers!
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