I don't think that's what I have. I have had cold-related issues for a couple of days, and that was the only instance of something, except fever, that could be related.
And no, I don't know. Maybe someone here knows something that would fit the literal translation, "Winter barf sickness", well.
"vinterkräksjuka" means "winter creep having a propensity to"
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I have yet to see an online translator that doesn't produce garbage when translating Swedish.