First time dealing with possible virus.

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I've thought about this a lot. I have a plant of this (originally from Ray) that gets terrible care. It doesn't have, and has never had, a single leaf spot. I forget to water it, I put it in too much sun, it gets low humidity, a rat bit into it.

I doubt your indoor humidity is very high in the winter; I recall México City being quite dry in winter. So I would keep it segregated. Maybe you can find some virus test strips eventually, either in México or another country.