<story><title>Substantial undocumented infection facilitates rapid dissemination of SARS-CoV2</title><url>https://science.sciencemag.org/content/early/2020/03/13/science.abb3221</url></story><parent_chain><item><author>cycrutchfield</author><text>This is not really valid due to fatality rate being heavily dependent on age, comorbidities, and healthcare quality (which is itself dependent on case load), and the distributions of these differ greatly across countries. But, sure, you could try to normalize these to infer the actual case load.</text></item><item><author>httpz</author><text>Assuming that someone who died from coronavirus is far more likely to have been tested for the virus than someone who&amp;#x27;s been infected by it, the true death rate of someone infected by the virus is probably far lower than the calculated death rate. (# of confirmed death &amp;#x2F; # of confirmed infections).&lt;p&gt;S.Korea did extensive testing, which reduces the number of unreported infections. So the calculated death rate in S. Korea is 4x lower than a comparable country like Spain, which has similar # of confirmed cases, population, GDP, and GDP per capita.&lt;p&gt;If we assume S. Korea&amp;#x27;s calculated death rate(&amp;lt;1%) is closer to the true death rate and apply it to other countries to derive the total # of infections (reported + unreported) based on the reported death count, we can see there may be far more infections than we know.</text></item><item><author>nmca</author><text>Does this mean the mortality rate is, approximately, 10x less than currently estimated?&lt;p&gt;(86% of cases unreported, eg about 1 in 10 reported, assume that number of unreported fatal cases is 0)&lt;p&gt;Edit: closer reading suggests the optimism is sadly unwarranted, the headline under-reporting number of 86% is from the early pre-travel ban model, post-travel-ban estimates give a 65% detection rate, combined with the increased number of cases in this later period this implies that naive mortality estimates are more like 2x off than 10x off.</text></item></parent_chain><comment><author>httpz</author><text>There is a lot of assuming going on so this doesn&amp;#x27;t actually prove anything but I think it&amp;#x27;s something worth thinking about.&lt;p&gt;Is Spain and S. Korea really that much different to have a 4x difference in death rate?</text></comment>
<story><title>Substantial undocumented infection facilitates rapid dissemination of SARS-CoV2</title><url>https://science.sciencemag.org/content/early/2020/03/13/science.abb3221</url></story><parent_chain><item><author>cycrutchfield</author><text>This is not really valid due to fatality rate being heavily dependent on age, comorbidities, and healthcare quality (which is itself dependent on case load), and the distributions of these differ greatly across countries. But, sure, you could try to normalize these to infer the actual case load.</text></item><item><author>httpz</author><text>Assuming that someone who died from coronavirus is far more likely to have been tested for the virus than someone who&amp;#x27;s been infected by it, the true death rate of someone infected by the virus is probably far lower than the calculated death rate. (# of confirmed death &amp;#x2F; # of confirmed infections).&lt;p&gt;S.Korea did extensive testing, which reduces the number of unreported infections. So the calculated death rate in S. Korea is 4x lower than a comparable country like Spain, which has similar # of confirmed cases, population, GDP, and GDP per capita.&lt;p&gt;If we assume S. Korea&amp;#x27;s calculated death rate(&amp;lt;1%) is closer to the true death rate and apply it to other countries to derive the total # of infections (reported + unreported) based on the reported death count, we can see there may be far more infections than we know.</text></item><item><author>nmca</author><text>Does this mean the mortality rate is, approximately, 10x less than currently estimated?&lt;p&gt;(86% of cases unreported, eg about 1 in 10 reported, assume that number of unreported fatal cases is 0)&lt;p&gt;Edit: closer reading suggests the optimism is sadly unwarranted, the headline under-reporting number of 86% is from the early pre-travel ban model, post-travel-ban estimates give a 65% detection rate, combined with the increased number of cases in this later period this implies that naive mortality estimates are more like 2x off than 10x off.</text></item></parent_chain><comment><author>TheOtherHobbes</author><text>It would be useful if this could be broken down into separate categories - estimated CFR without medical intervention, and likely CFR at various levels of intervention.&lt;p&gt;The former suggests what your population mortality rate will be if your healthcare system is overwhelmed, and could possibly be derived from Italian data. The latter gives you a resources vs effectiveness sweet spot that maximises health system throughput, so you can save the maximum number of lives over time given the resources you have (or can build&amp;#x2F;find.)&lt;p&gt;The age profile is relevant, but worryingly there seem to be a number of reports that it&amp;#x27;s not just the over-65s who are at risk.&lt;p&gt;I haven&amp;#x27;t seen anything more recent about this than the Chinese estimates from a month or so ago.</text></comment>