
Ask HN: Why didn’t SARS spread like Covid-19? - andrewseanryan
I recently read an article from Bloomberg claiming that SARS was more contagious (3.0 vs 2.8 RO) than COVID-19. If this is true, why were there only 8,000 cases? Here is the link: https:&#x2F;&#x2F;www.bloombergquint.com&#x2F;opinion&#x2F;how-bad-is-the-coronavirus-let-s-compare-with-sars-ebola-flu
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detaro
I've seen two reasons named:

a) SARS had a shorter incubation period, so people got seriously ill and
isolated quicker

b) The virus now is a lot more present in the upper respiratory system, even
before symptoms appear, and thus spread more easily during the longer
unrecognized period, whereas if you were highly contagious for SARS you also
were quite sick already

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ohiovr
I read recently that SARS symptoms appeared near the infection time so it was
easier to observe. MERS had a small replication value so it wasn't as
virulent.

