Sunday, August 16, 2020

The Truth This Week, from TWiV


TWiV #654 brings not so much news, as revisions of news and critical assessment of news.




Here is the link for those who have 2 1/2 hours:
https://www.microbe.tv/twiv/twiv-654/



Some salient points:
1/ Post COVID 19 lymphoma is not yet  a documented complication of SARS COv-2, but there are a few case reports and this same phenomenon has been seen in other viruses, namely HIV and Burkett's Lymphoma

2/ Viral droplet  spread prevention by masks: studies on this are surprisingly difficult to find, at least good studies. But thus far, the evidence and mostly the theory suggests masks are important. Controlled studies (with controls who do not wear masks) will not be done for ethical reasons. (The parachute effect: You cannot do control studies on people jumping out of planes without parachutes as controls.)

3/ An Op Ed in the NYT by a pediatrician suggesting children are not playing much of a role in the spread  is a bewildering position, which is likely flat out wrong. Children, whether or not they get symptomatic, likely do bring virus home and out into the community. 

4/ Postural Hypotension and Tachycardia is a syndrome seen in some patients.

5/ Return of taste and smell after the anosmia of COVID may herald recovery from the virus.




6/ "Long haulers" --patients who continue to be symptomatic with fatigue, weakness for months following the acute phase.

7/ Convalescent sera with IgG antibodies studies have been a mess, because so many other therapies are given at the same time so it's difficult to know which therapy helped or even if any of them helped. The TWiV faculty continues to say the idea of anti viral therapy making a difference is hard to fathom because it's not the phase of the disease when the virus is replicating that gets people sick--it's the cytokine storm following that brief phase that kills people. 

8/ Testing is improving in the sense that turn around time is diminishing, but the only real strategy which might work is the salivary quick tests.
Many doctors are still saying "the tests are inaccurate" and when you say they are not inaccurate the doctors say, "But what about false negatives?" 
This means too many doctors have remain ignorant on this point.
What you want in a screening test is a test which captures infectious patients, not infected patients.
If the test misses an infected patient who is not infectious that is fine.
Patients are likely only infectious briefly, when they have millions to billions of virions in their noses and throats. During that phase, the Michael Mina mentioned quick saliva test will be reliably positive. 
You could pump out these simple antigen salivary tests which work like home pregnancy tests and use these to keep home infected school children, factory workers and others.

9/ Rules for testing accuracy during a pandemic should be different from when there is not a pandemic.

10/ The Russian vaccine is not ready for prime time. "They were Rushing all right."
It's an adenovirus vector vaccine--and as TWiV has discussed before, if you attach a vaccine to an adenovirus and lots of people have antibodies to that adenovirus, the vaccine may be ineffective.  Even so, the Russian vaccine will not be available to the general population until January 2021 and the manufacturer will be only to make only 1 million doses a year. So it will not be a solution. 

12/ Vaccines may well not provide long term (years) protection because coronaviruses typically do not elicit that, even from native disease. Likely a few months or maybe a year, if we're lucky, but hopefully recurrent infections will be milder.  Vaccines under development are mostly to the spike protein and this is a gamble, and we need vaccines to other parts of the virus.