<story><title>Johnson and Johnson single-shot vaccine appears 66% effective in global trial</title><url>https://www.cbc.ca/news/health/johnson-johnson-covid-vaccine-trial-1.5893009</url></story><parent_chain><item><author>m12k</author><text>I originally thought the Oxford&amp;#x2F;AstraZeneca vaccine was significantly behind the mRNA vaccines in efficacy. But then I learned that the Oxford trials PCR-tested every participant regularly, while the Pfizer and Moderna trials only tested participants that were showing symptoms. So there&amp;#x27;s a very real chance that behind that ~95% number the mRNA vaccines also had asymptomatic cases that were never discovered during trials, and the actual protection is nearly the same as the Oxford one. The mRNA vaccines still seem like a great leap forward, and they don&amp;#x27;t come with the potential complications of resistance to the vector virus that adenovirus-based vaccines do - but I&amp;#x27;m less sure now that they actually offer better protection overall.</text></item><item><author>tpmx</author><text>The mRNA vaccines are obviously the gold standard, they&amp;#x27;re what you want, if you&amp;#x27;re in a position to pick.&lt;p&gt;The traditional vaccines, like this one and the Astra Zeneca one appear to be efficient at preventing hospitalization&amp;#x2F;death. That&amp;#x27;s great - it will ease the extreme load on the hospitals, and also reduce deaths greatly.&lt;p&gt;What I&amp;#x27;m concerned about is the long-term chronical diseases that&amp;#x27;s been reported (&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.mayoclinic.org&amp;#x2F;diseases-conditions&amp;#x2F;coronavirus&amp;#x2F;in-depth&amp;#x2F;coronavirus-long-term-effects&amp;#x2F;art-20490351&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.mayoclinic.org&amp;#x2F;diseases-conditions&amp;#x2F;coronavirus&amp;#x2F;i...&lt;/a&gt;), hitting a substantial part of the infected.&lt;p&gt;We need more clarity to which degree the non-mRNA-vaccines prevent these pretty horrobile chronic diseases.</text></item></parent_chain><comment><author>mlyle</author><text>No.  AstraZeneca &lt;i&gt;also&lt;/i&gt; tested with weekly PCR surveillance.  But the efficacy numbers we&amp;#x27;re comparing between AstraZeneca and the mRNA vaccines are measures of how often they prevents symptomatic illness-- a very similar standard to that used in the Moderna and Pfizer trials (but not absolutely, directly comparable).&lt;p&gt;Unfortunately, the AZ trial is a mess.  One way it was a mess is that the error bars on how much they prevent all illness (not just symptomatic illness) go all the way down to 1%.</text></comment>
<story><title>Johnson and Johnson single-shot vaccine appears 66% effective in global trial</title><url>https://www.cbc.ca/news/health/johnson-johnson-covid-vaccine-trial-1.5893009</url></story><parent_chain><item><author>m12k</author><text>I originally thought the Oxford&amp;#x2F;AstraZeneca vaccine was significantly behind the mRNA vaccines in efficacy. But then I learned that the Oxford trials PCR-tested every participant regularly, while the Pfizer and Moderna trials only tested participants that were showing symptoms. So there&amp;#x27;s a very real chance that behind that ~95% number the mRNA vaccines also had asymptomatic cases that were never discovered during trials, and the actual protection is nearly the same as the Oxford one. The mRNA vaccines still seem like a great leap forward, and they don&amp;#x27;t come with the potential complications of resistance to the vector virus that adenovirus-based vaccines do - but I&amp;#x27;m less sure now that they actually offer better protection overall.</text></item><item><author>tpmx</author><text>The mRNA vaccines are obviously the gold standard, they&amp;#x27;re what you want, if you&amp;#x27;re in a position to pick.&lt;p&gt;The traditional vaccines, like this one and the Astra Zeneca one appear to be efficient at preventing hospitalization&amp;#x2F;death. That&amp;#x27;s great - it will ease the extreme load on the hospitals, and also reduce deaths greatly.&lt;p&gt;What I&amp;#x27;m concerned about is the long-term chronical diseases that&amp;#x27;s been reported (&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.mayoclinic.org&amp;#x2F;diseases-conditions&amp;#x2F;coronavirus&amp;#x2F;in-depth&amp;#x2F;coronavirus-long-term-effects&amp;#x2F;art-20490351&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.mayoclinic.org&amp;#x2F;diseases-conditions&amp;#x2F;coronavirus&amp;#x2F;i...&lt;/a&gt;), hitting a substantial part of the infected.&lt;p&gt;We need more clarity to which degree the non-mRNA-vaccines prevent these pretty horrobile chronic diseases.</text></item></parent_chain><comment><author>tpmx</author><text>&amp;gt; But then I learned that the Oxford trials PCR-tested every participant regularly, while the Pfizer and Moderna trials only tested participants that were showing symptoms.&lt;p&gt;That seems substantial, weird and important. Source?</text></comment>