Thanks for bringing that up, mrsD, but although I suspect this could be viral (neurotoxic) in nature, I don't think it is Zika / Dengue / Chikungunya (prevalent in Puerto Rico) for the following reasons.

1. Zika is asymptomatic in 80% of infected people
2. Zika only lasts a week in the blood so getting a test now would be fruitless as my symptoms started months ago
3. Zika's primary symptoms in the 20% of cases are things like fever, nausea, skin rash, joint pain or swelling, none of which I have had.
4. There's no evidence of Zika causing fasciculations / muscle twitches / electric shocks in a person, which are my main complaints.

I wish it was as easy as identifying a virus and just waiting it out. Ciguatera is actually closer in nature to what I have -- a fish neurotoxin that affects the gut. But I haven't eaten any fish here so there'd be no way for me to get it, and I don't have the classic cold/hot reversal symptoms. However the idea of a neurotoxic virus makes sense to me since my symptoms did improve over time (with the exception of the current "flare-up" state).