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  • North Korea’s Kim Jong Un declares victory over Covid pandemic

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  • Biden back in isolation after rebound case of COVID-19

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  • Biden tests positive for COVID-19 after Paxlovid rebound

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  • President Biden tests positive again for Covid-19

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  • 'I'm feeling great': Biden speaks after testing negative for Covid

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  • Biden’s COVID symptoms said to be ‘almost completely resolved’

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  • Biden’s Covid-19 symptoms improve, according to doctor

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  • Biden says he is ‘feeling good’ despite sore throat, cough from Covid

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  • How genetics, other factors can prevent Covid infections

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  • What we know about long COVID: Symptoms, causes, conditions

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  • Biden’s doctor says his condition continues to improve

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  • White House says President Biden improving from Covid

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How many days is someone contagious before coronavirus symptoms start to appear?

01:33

Many are wondering how many days someone is contagious with coronavirus before symptoms start to appear. NBC News medical correspondent Dr. Natalie Azar explains how mild symptoms are driving this epidemic.