Since the previous expert has opted out, I am answering your questions.
1. Would a bullseye rash from Lyme disease take a month to show up?
Usually the Bull's eye rash would present in 7-14 days and persists for 3 weeks of the tick bite. It is rare to bull's eye rash to take a month to show up. Though the medical literature says that it can appear in the range of 1-33 days. Please the reference resource;
2. What else causes a bullseye rash?
The rash has also been described in the Southeastern United States in association with Amblyomma americanum - the lone star tick. Please see this authentic medical reference;
3. The blurry vision, redness and light sensitivity has substantially improved. Would this happen if there is another underlying cause?
A generalized cause, manifesting uveitis has less likelihood of improving in 1-2 weeks usually.
Please feel free for your follow up questions.
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