Prevent Epidemics has a Weekly Science Review that provides brief summary and discussion of major peer-reviewed scientific articles on the pandemic for the past week, in addition to "In-Depth" overviews of key topics of current interest.
In the August 29-September 11 issue, they have an outstanding in depth description of how the emergency use authorization (EUA) procedure works, especially relevant given the hints that a vaccine could be given EUA based on preliminary clinical trial results in the next two months if results are good, and also discusses specific issues in using this mechanism for vaccines for healthy people as opposed to its usual use for treatments for patients with severe and life threatening disease.
A few key points along with some commentary from me:
The 3 EUA's given so far are for Hydroxycholoroquine, Remdesivir, and convalescent plasma, with mixed success -- the HCQ approval was rescinded, and the convalescent plasma approval was acknowledged to be based on scant evidence but remains.
Usually these are given for diseases with no known treatments, to help patients with advanced disease who are at risk of death who have no known good options. Giving one for a vaccine that will in principle be given society-wide brings greater risks since it will be given to otherwise healthy people. The devastating impact of the pandemic in the world justifies its consideration, but must bewith extreme caution since rash approval of a vaccine that proves to be ineffective or worse yet, unsafe, could lead to devastating consequences of its own including undermining public trust in future vaccines that might be more effective.
The summary mentions that for most vaccines, the side effects occur in the first 6 weeks, so in that case the phase 3 studies should provide ample evidence of safety. However, given the potential for "antibody-mediated enhancement", extra care needs to be taken to ensure this does not occur from a particular vaccine. The idea of "antibody-mediated enhancement" is that the worse advanced cases of COVID-19 involve an out of control immune/inflammatory response, a "cytokine storm", that does the greatest damage and leads to many of the deaths, as well as the long-term repercussions that some recovered patients experience. They have to be very careful that the antibody response induced by the vaccine is effective and neutralizes the virus, and does not in substantial cases exacerbate the disease in those who are infected by increasing the probability of this inflammatory response, in principle potentially leading to more advanced disease. The scientists working on these studies are well aware of this issue, but is just another reason why caution must be shown to not rush the vaccine before it is demonstrated safe and effective.
Second, they give an explanation of how deaths are attributed to COVID-19 which can help overcome the misunderstandings that led many to believe the false narrative that because 94% of COVID-related deaths had other conditions listed on the death certificate that this means that these deaths were spuriously related to COVID-19.
They also summarize 3 articles published in that time period:
One in JAMA describing a case study of a bus-induced super spread event in China that affirms the notion that airborne virus can seed super spread events under the right conditions.
One in NEJM demonstrating that saliva swabs are just as accurate as nasopharyngeal swabs (i.e. the giant Q-tip put deeply into your nose to your throat that feels like it is going to your brain).
Another in NEJM summarizing results from Iceland who did near population-wide testing for SARS-CoV-2 and did follow up antibody screening, finding that 91% of those recovered tested positive for antibodies, and 90% of those had no decrease in antibodies evident 4 months later.
I recommend this as a reliable, clearly written resource of emerging knowledge about the pandemic.
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