TWiV 632 once again contains nuggets of great value. It remains the best source about SARS COV-2 and the disease it causes: COVID19, but it takes 2 hours to listen to, which has discouraged even many physicians from cleaving to it.
Apologies to the TWiV crew, but so many of my friends demanded a summary, I felt compelled.
Here's the link to the actual show, which I highly recommend:
https://www.virology.ws/2020/06/29/twiv-632-countering-a-miasma-of-anti-think/
Daniel Griffin reviewed the dexamethasone study out of Britain which is likely an advance: As he has said previously, it looks as if COVID 19 typically has a one week phase during which, if you are going to be really sick with this disease, you feel ill then, with cough, fever, malaise, achy. It is during this time the virus is replicating full tilt.
Nuggets:
1. Many people, from 40-70%, especially younger folks, have few or no symptoms but shed virus prodigiously during this first week.
During this week is when antiviral drugs like Tosi and remdesivir may help by thwarting viral replication.
2. During the 2nd phase, the 2nd week, is when all Hell breaks loose and the immune system, in some patients, fires off like an ammunition dump hit by a rocket and "cytokine storm" explodes.
During this phase glucocorticoids (cortisol, dexamethasone, hydrocortisone, prednisone) likely can make a significant difference in survival--the Brits showed a 30% reduction in deaths using dexamethasone.
He is likely correct to say if dexamethasone helps likely all the members of this class will.
He does not explain sufficiently why this class of drugs had not been used more widely before this study: the fear was using a drug which dampens immune response in the face of an infective agent (i.e. the virus) you'd be stripping the body of its only defense against the virus, namely a fully functioning immue system (B cells and T cells, innate and adaptive immune systems.)
This diminishing of the anti infection firepower turns out to be offset by the benefit of protecting the body against the police called out to defend the body, because at this phase, it's the police, who start shooting good guys and bad guys alike, who cause most of the trouble.
Griffin repeats one thing which sets the Phantom's hair on fire: He once again recounts stories of a time when he was in training when medicine was practiced on the basis of pronouncements from pompous older physicians about how to practice based on the experience of these doctors rather than on controlled, prospective studies. Griffin trained in NYC (the Phantom estimates in the 1980's-1990's) and the Phantom can say with great authority the great majority of physicians at the teaching hospitals in NYC during those years made great efforts to support their recommendations by reference to the medical literature of controlled studies. Apparently, Dr. Griffin had some run ins with some officious, supercilious docs who thought their own experience was better than prospective, controlled, randomized studies and he has never quite recovered.
But as Siddhartha Murkhurjee has pointed out, there are simply not enough studies for every question to be able to use studies to guide clinical practice in every question.
Another quibble, the Phantom has it on good authority that as far back as February all patients admitted to the Mt. Sinai hospital system with COVID 19 got glucocorticoids on admission but since there was no placebo arm and since the patients were given glucocorticoids in some cases while they were in the viral replication phase, the results were not encouraging.
3. After patients get past the 1st two to three weeks, they are set ups for coagulation events: strokes, clots to the legs or feet cutting off arterial blood flow and requiring amputation and anticoagulation can save patients from this fate.
So treatment of patients infected has improved substantially and has been guided, increasingly, by better controlled studies.
Racaniello ruminated on how this siege is likely to end, along with Rich Condit: They think it will become like other coronoviruses before, a sort of ever present virus, which children will get, get over and be immune to, never really getting all that sick. There will then be no need for a vaccine because it will be controlled by herd immunity, but it will always be with us, like the other coronoviruses which give us the "common cold."
A vaccine sometime in the next 18 months would help save older members of our population, say people born between 1940 and 1970, who might not survive an encounter with this virus and will be long dead before SARS COV-2 becomes just another coronavirus.
Brianne Barker noted that antibodies, which are made by B cells (and might be thought of as the small arms fire of the immune system) likely do not last long and even if they do, might not be very important in protecting against illness from the virus. It's the T cells, the heavy artillery, which may kill off the virus or at least protect against its worse ravages and there are no readily available, widespread tests currently being used to study or track T cell response. During a discussion of the emails she mentioned a $2000 machine which could be used to measure T cell function and could be used in studies of how the population is responding to SARS COVd-2. But the big point is, even if we could readily measure antibodies, it may not be the antibodies which confer protection.
So that's the quick and dirty on TWiV #632.
Apologies to TWiV, but we need a brief summary.
NB: THIS IS NOT A SUMMARY AUTHORIZED BY TWiV OR ANY MEMBERS OF THE ESTIMABLE TWiV TEAM, WHO ARE STALWARTS, ONE AND ALL.
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