'Positive' and 'negative' control swabs in Covid-19 test kits only used for quality control, experts say
https://factcheck.afp.com/positive-and-negative-control-swabs-covid-19-test-kits-only-used-quality-control-experts-sayCopyright AFP 2017-2022. All rights reserved. An image purporting to show components of a Covid-19 test kit has been shared in multiple posts on Facebook alongside a claim that the “positive” a