Brief Answer:
It is not necessary

Detailed Answer:
Hello,

Thanks for posting your query,

I do not think it will be necessary for your daughter to inform her boss. I understand that your question is whether or not the virus (herpes zoster) that causes shingles is could be contagious? The answer is yes but if there is no direct contact while the infection is still present, there would not be any infection. I understand she is working at a bar, but she should not be worried about contaminating others i.e if she can keep from getting close contacts with people. I see she is already on valicyclovir which will also help control the virus.
Shingles which occurs later on in life is as result of prior infection with chicken pox which becomes inert and later reactives as an individual grows older. The prediposing factors for shingles is mainly immunodepressive state. I do suggest she gets checked up for immuno-status and also do a HIV serology test.
As for her, she should keep this to herself as I do not think it will be a problem with her work and besides her boss might take things orderwise (since he might have little notion about the diseases).

Hope this helps and wish her the best
Dr. Nsah

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