<div dir="ltr"><div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><span style="font-family:Arial,Helvetica,sans-serif">On Mon, Dec 22, 2025 at 10:07 AM Jason Resch via extropy-chat <<a href="mailto:extropy-chat@lists.extropy.org">extropy-chat@lists.extropy.org</a>> wrote:</span></div></div><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr"><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><font size="4" face="georgia, serif"><i><span class="gmail_default" style="font-family:arial,helvetica,sans-serif">> </span>We know that last year's flu vaccine had negative efficacy (those who received it were more 26.9% likely to get the flu</i></font></blockquote><div><br></div><div><span class="gmail_default" style=""><font face="arial, helvetica, sans-serif"></font><font size="4" style="" face="tahoma, sans-serif"><b style="">But d</b></font></span><font size="4" face="tahoma, sans-serif"><b>o we know that?<span class="gmail_default" style="">!</span><span class="gmail_default" style=""> I had the following conversation with Gemini AI:</span></b></font></div><div><span class="gmail_default" style=""><font size="4" face="tahoma, sans-serif"><b><br></b></font></span></div><font size="4" face="tahoma, sans-serif"><b>ME: Somebody told me that " <i>last year's flu vaccine had negative efficacy (those who received it were more 26.9% likely to get the flu</i>", is that true!?</b></font></div><div class="gmail_quote gmail_quote_container"><font face="tahoma, sans-serif" size="4"><b><br></b></font></div><div class="gmail_quote gmail_quote_container"><font size="4"><font face="tahoma, sans-serif">Gemini<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">: </span></font><span class="gmail-citation-19" style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px">That claim refers to a specific, controversial </span><b style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><span class="gmail-citation-19" style="line-height:1.15;margin-top:0px">preprint study</span></b><span class="gmail-citation-19 gmail-citation-end-19" style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"> <b>(not yet peer-reviewed)</b> from the Cleveland Clinic that was released in April 2025.</span></font></div><p></p><p style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><font size="4">While the "26.9%" number (often rounded to 27%) does appear in that specific paper, the interpretation that the vaccine is "dangerous" or "causes the flu" is considered a significant misreading of the data by the medical community.</font></p><h3 style="font-family:"Google Sans",sans-serif;line-height:1.15;margin-top:0px"><font size="4">1. The Study in Question</font></h3><p style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><font size="4"><span class="gmail-citation-18 gmail-citation-end-18" style="line-height:1.15;margin-top:0px">The study analyzed over 50,000 employees at the Cleveland Clinic during the 2024–2025 flu season.<span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span></span><span class="gmail-citation-17" style="line-height:1.15;margin-top:0px">It found that vaccinated employees had a </span><b style="line-height:1.15;margin-top:0px"><span class="gmail-citation-17" style="line-height:1.15;margin-top:0px">27% higher risk of testing positive</span></b><span class="gmail-citation-17 gmail-citation-end-17" style="line-height:1.15;margin-top:0px"> for the flu compared to unvaccinated employees.</span> <span class="gmail-citation-16 gmail-citation-end-16" style="line-height:1.15;margin-top:0px">This resulted in a calculated "negative effectiveness" of <span class="gmail_default" style="font-family:arial,helvetica,sans-serif"> </span></span><b style="line-height:1.15;margin-top:0px"><span class="gmail-math-inline" style="line-height:1.15;margin-top:0px">-26.9<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">%</span></span></b></font></p><p></p><h3 style="font-family:"Google Sans",sans-serif;line-height:1.15;margin-top:0px"><font size="4">2. Why the Result is Controversial</font></h3><p style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><font size="4">Independent experts and the study authors themselves have pointed out several reasons why this number doesn't mean the vaccine makes you sick:</font></p><ul style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><li style="line-height:1.15;margin-top:0px"><p style="line-height:1.15;margin-top:0px"><font size="4"><span class="gmail-citation-14" style="line-height:1.15;margin-top:0px"></span><b style="line-height:1.15;margin-top:0px"><span class="gmail-citation-14" style="line-height:1.15;margin-top:0px">Testing Bias:</span></b><span class="gmail-citation-14 gmail-citation-end-14" style="line-height:1.15;margin-top:0px"> One major factor is that vaccinated healthcare workers are often more "health-conscious" and significantly more likely to get tested if they feel a slight sniffle.</span> If the vaccinated group tests more often, they will naturally record more "positive" results than an unvaccinated person who just stays home and rests without a test.</font></p><p></p></li><li style="line-height:1.15;margin-top:0px"><p style="line-height:1.15;margin-top:0px"><font size="4"><b style="line-height:1.15;margin-top:0px">Workplace Policies:</b> Unvaccinated employees often face stricter masking or social distancing requirements in hospital settings. This means the unvaccinated group may have been better protected by physical barriers (masks), making the vaccine's effect look worse by comparison.</font></p></li><li style="line-height:1.15;margin-top:0px"><p style="line-height:1.15;margin-top:0px"><font size="4"><b style="line-height:1.15;margin-top:0px">Infection vs. Severity:</b><span class="gmail-citation-13 gmail-citation-end-13" style="line-height:1.15;margin-top:0px"> The study only looked at whether people tested positive.</span> <span class="gmail-citation-12" style="line-height:1.15;margin-top:0px">It did </span><b style="line-height:1.15;margin-top:0px"><span class="gmail-citation-12" style="line-height:1.15;margin-top:0px">not</span></b><span class="gmail-citation-12 gmail-citation-end-12" style="line-height:1.15;margin-top:0px"> measure how many people ended up in the hospital.</span><b> <span class="gmail-citation-11 gmail-citation-end-11" style="line-height:1.15;margin-top:0px">Historically, even when a flu vaccine is a "poor match" for preventing infection, <u>it remains highly effective at preventing death and severe lung complications</u>.</span></b></font></p><div class="gmail-source-inline-chip-container gmail-ng-star-inserted" style="line-height:1.15;margin-top:0px"><font size="4"><br></font></div><p></p></li></ul><h3 style="font-family:"Google Sans",sans-serif;line-height:1.15;margin-top:0px"><font size="4">3. The National Data (CDC)</font></h3><p style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><font size="4">The broader data from the CDC for the same season (2024–2025) told a very different story. <span class="gmail-citation-10" style="line-height:1.15;margin-top:0px">Their multi-state networks estimated the vaccine was actually </span><b style="line-height:1.15;margin-top:0px"><span class="gmail-citation-10" style="line-height:1.15;margin-top:0px">36% to 54% effective</span></b><span class="gmail-citation-10" style="line-height:1.15;margin-top:0px"> at preventing outpatient flu visits and roughly </span><b style="line-height:1.15;margin-top:0px"><span class="gmail-citation-10" style="line-height:1.15;margin-top:0px">41% to 55% effective</span></b><span class="gmail-citation-10 gmail-citation-end-10" style="line-height:1.15;margin-top:0px"> at preventing hospitalizations.</span><br></font></p><p style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><font size="4"><span class="gmail-citation-10 gmail-citation-end-10" style="line-height:1.15;margin-top:0px"><br></span></font></p><p></p><hr style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><h3 style="font-family:"Google Sans",sans-serif;line-height:1.15;margin-top:0px"><font size="4">Summary Table</font></h3><table style="margin-bottom:32px;font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><thead style="line-height:1.15;margin-top:0px"><tr style="line-height:1.15;margin-top:0px"><td style="border:1px solid;line-height:1.15"><strong style="line-height:1.15;margin-top:0px;margin-bottom:0px"><font size="4">Feature</font></strong></td><td style="border:1px solid;line-height:1.15"><strong style="line-height:1.15;margin-top:0px;margin-bottom:0px"><font size="4">Cleveland Clinic Preprint</font></strong></td><td style="border:1px solid;line-height:1.15"><strong style="line-height:1.15;margin-top:0px;margin-bottom:0px"><font size="4">CDC National Estimates</font></strong></td></tr></thead><tbody style="line-height:1.15;margin-top:0px"><tr style="line-height:1.15;margin-top:0px"><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><b style="line-height:1.15;margin-top:0px"><font size="4">Conclusion</font></b></span></td><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><font size="4">Negative Efficacy (<span class="gmail-math-inline" style="line-height:1.15;margin-top:0px">-26.9<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">%</span></span>)</font></span></td><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><font size="4">Positive Efficacy (<span class="gmail-math-inline" style="line-height:1.15;margin-top:0px">+36<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">% </span></span>to <span class="gmail-math-inline" style="line-height:1.15;margin-top:0px">+54<span class="gmail_default" style="font-family:arial,helvetica,sans-serif">%</span></span>)</font></span></td></tr><tr style="line-height:1.15;margin-top:0px"><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><b style="line-height:1.15;margin-top:0px"><font size="4">Population</font></b></span></td><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><font size="4">Healthy healthcare workers in Ohio</font></span></td><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><font size="4">General public (all ages/locations)</font></span></td></tr><tr style="line-height:1.15;margin-top:0px"><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><b style="line-height:1.15;margin-top:0px"><font size="4">Status</font></b></span></td><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><font size="4">Preprint (Not peer-reviewed)</font></span></td><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><font size="4">Official Surveillance Data</font></span></td></tr><tr style="line-height:1.15;margin-top:0px"><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><b style="line-height:1.15;margin-top:0px"><font size="4">Interpretation</font></b></span></td><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><font size="4">Likely skewed by testing behavior</font></span></td><td style="border:1px solid;line-height:1.15"><span style="line-height:1.15;margin-top:0px"><font size="4">Standard measure of public health impact</font></span></td></tr></tbody></table><p style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><font size="4"><b style="line-height:1.15;margin-top:0px">The Bottom Line:</b> The "negative efficacy" was a finding in one specific group of hospital workers, likely due to how often they were tested or masked. It does not reflect the overall performance of the vaccine for the general public.</font></p><p style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><font size="4"><br></font></p><p style="font-family:"Google Sans Text",sans-serif;line-height:1.15;margin-top:0px"><b style="color:rgb(80,0,80);font-family:Arial,Helvetica,sans-serif"><font face="tahoma, sans-serif"><font size="4">John K Clark See what's on my new list at </font><font size="6"><a href="https://groups.google.com/g/extropolis" rel="nofollow" target="_blank">Extropolis</a></font></font></b></p><font size="1" color="#ffffff">7dd</font><div class="gmail_quote gmail_quote_container"><font face="tahoma, sans-serif" size="4"><b><br></b></font></div><div class="gmail_quote gmail_quote_container"><font face="tahoma, sans-serif" size="4"><b><br></b></font><div> </div><div dir="ltr" class="gmail_attr"><br></div><div dir="ltr" class="gmail_attr"><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div><br><div><br></div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Dec 22, 2025 at 7:08 AM John Clark via extropy-chat <<a href="mailto:extropy-chat@lists.extropy.org" target="_blank">extropy-chat@lists.extropy.org</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div style="font-family:arial,helvetica,sans-serif"><font size="4"><b>The following is from the December 17, 2025 issue of the journal Nature: </b></font></div><div style="font-family:arial,helvetica,sans-serif"><font size="4"><br></font></div><font size="4"><b><i>"A study of 9,000 adults found that those who received the flu shot were 34% less likely to experience serious cardiovascular events in the next year than were those who did not receive the vaccine. For people with recent cardiac issues, the benefits were even more pronounced, with a 45% lower risk of a serious event.</i>[...] <i>Clinicians should make it clear that for individuals who are at elevated risk of cardiovascular disease, the flu vaccine isn’t just a ‘nice to have’ — it’s a clinical necessity."</i></b></font><div style="font-family:arial,helvetica,sans-serif"><font size="4"><br></font></div><div><a href="https://www.nature.com/articles/d41586-025-03598-0?utm_source=Live+Audience&utm_campaign=82ce72787e-nature-briefing-daily-20251218&utm_medium=email&utm_term=0_-33f35e09ea-50169436" target="_blank"><font size="4" face="tahoma, sans-serif"><b>There's already a vaccine for heart disease</b></font></a><br></div><div style="font-family:arial,helvetica,sans-serif"><br></div></div></blockquote></div>
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