Are coronavirus antibody tests worth the money? As a GP, I thought I'd give one a try | Ann Robinson

The commercial kits are tempting, but offer little certainty when we aren't even sure that antibodies confer immunity

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Does anyone know of a private Covid antibody test that is properly reliable?" asked one of my friends on WhatsApp.

The question made me curious. Having antibodies, of course, means you've been exposed to the virus and you're unlikely to spread it. But with possible false negatives, it's no guarantee and you'd still want to keep a distance from vulnerable people. Also no one knows how long the immunity lasts.