Brief Answer:
the primary lesion looks like a red papular rash

Detailed Answer:
Hello,

Thanks for posting on XXXXXXX

I am pleased to be able to answer your health query.

After taking a look at your photo, I could single out the primary lesion as being a red papular rash (isolated). Well your history of shingles probably has nothing to do with the rash, as shingles usually occur as multiple rashes.
I would have loved to know if the rash is itchy/sore/painful, duration from time of onset and if you might noticed any other occurrence on your body. A rash can be caused, directly or indirectly, by a bacterial, viral, or fungal infection. Alternatively, a rash may be unrelated to an infectious organism, such as from an underlying medical illness. Yours seem to be of infectious origin, probably bacteria.
Without any medical intervention, it might clear off on its on. It does not seem like a rash related to any underlying chronic medical condition, but rather some sort of a folliculitis. Just stay calm and do watch of subsequent occurrences (if any), then you will need medical attention.

Hope this helps and wish you the best.
Dr. Nsah

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