I am glad to hear you are well enough to be unsure. Just to nitpick, but it is being a silent carrier (heterozygous) that provides the resistance to cholera -

I am glad to hear you are well enough to be unsure. Just to nitpick, but it is being a silent carrier (heterozygous) that provides the resistance to cholera - until very recently few suffers of cf lived long enough to die of anything else.