I travelled North, South, East and West on Zanzibar and never saw anything that made me concerned for my safety, I have not heard any rumours about safety being an issue. Basically treate Zanzibar like any other East African country, sensibly ...
Congratulations and have a great time.
P.S. where exactly are you going to on Zanzibar maybe I or someone else has been there, after all it is a fair size island and can take 3 hrs from end to end in a cab, 5-6 hrs on a bus.
Phil J
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