This COVID-19 explainer from Beth Marie Mole is one of the best out there. [arstechnica.com]

Please go read it, you'll learn a lot from it.
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@joe What are her sources? CDC? WHO??
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@MrFresh The WHO, CDC, the European health agencies and various others like experts and professionals. Should read it in full.
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@joe Yes, reading each link does show the sources. It would be convenient to cite that in the introductory paragraph.
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