Sunday, April 5, 2020

COVID19 for Dummies: Meaning, Just About All Of Us

A   disclaimer.  The Phantom is not an Infectious Disease specialist and has no more than a reading/podcast listening  knowledge of COVID19.

But one thing the Phantom can do is to detect quality, or lack of it,  in the folks who want to tell you about COVID19.

That means the Phantom knows that Dr. Nicole Saphier of FOX & Friends and Dr. Oz, of same and Jared Kushner, President Trump, Sean Hannity, Alex Jones, Rush Limbaugh all fall into the same category:  sources not to be trusted on the topic of COVID19. 
They are not credible sources, with respect to virology.
They are, as our President would say: "Incredible."
An Excellent Source of Reliable Thought and Information

But don't despair:  there are good sources.
 Anthony Fauci, MD has been reliable, open, and, as most really good doctors are: he is more humbled by what he does not know than he is impressed with his own mastery.

Then there are the folks who have done a podcast for geeks called "This Week in Virology" which is the best single source of information, science and clarity about COVID19 of which the Phantom is aware.

The trouble is, this is a podcast by and for geeks, and they use a vocabulary which likely will lose the average lawyer, journalist, plumber, school teacher. 

So the Phantom has undertaken a project in translation. This is not something the Phantom has been trained for, but for now, he tries to fill a void. The Phantom has listened to the most salient episodes (#595 & # 598) multiple times and they are so densely packed, he knows he has more listening to do.

Dickson Despommier

For those who want real information, the Phantom urges the reader to go to these podcasts: But be warned, each is an hour long. On the other hand, perfectly timed for walking the dog.

Here are some questions:
1. How many people get a dose of COVID19 and never become symptomatic?
2. Can these people shed virus and infect their family members, coworkers or other more casual contacts?
3. How long does the carrier shed?
4. Is it shed by droplets, urine, stools?
5. Once on board, what factors determine whether someone shrugs it off or gets sick or dies?
6. How much of a risk for carrier state are cats and dogs?
7. Is hydroxy chloroquine the answer? By what mechanism does it work? 
8. How effective are masks?
9. What is the prevalence, the mortality rate of COVID19?
10. How do you know if you have COVID19  or have had it?
11. What progress has been made on treatment?
12. What is "Cytokine storm"?
Kathy Spindler

Some tentative answers:
1. Asymptomatic people: We cannot know this without a certain type of study, which as yet has not yet been done. A study of people in Washington State of people who showed up at a drive in testing center because they were either worried or had symptoms showed that people with no symptoms were +10% for virus, whereas people with fever, cough, aches, fatigue, abdominal pain were +75% of the time. 
The more symptoms you had, the more likely you were to be + on PCR testing.

PCR looks for molecular material and indicates the presence of the virus.
To know if someone who is negative for virus on PCR has already fought off the disease, you need antibody testing. 
There are two types of antibodies: IgM, the first antibodies within 7 days of arrival of infection. IgG the antibodies which rise 7-14 days later and may confer long term immunity.

2. Silent shedders: are clearly a reality. Typhoid Mary did not know she was shedding typhoid because she was asymptomatic.

3. How long does the carrier shed?  
Depends on what you measure. Present in droplets sprayed out by patients for 7-14 days after cough ends. In stool, maybe 3 weeks. On surfaces, depends on the surface, from 3 weeks to 4 days.

4. Virus has been found in all these sources, and gets in via eye, mouth ports of entry.

5. Who fights it off and who dies? Why?
Probably there are "host factors" and "virus factors."
Virus factors include the dose of virus particles, virions. This is likely why the people intubating (putting tubes in tracheas) in the hospitals have over a 30% chance of getting COVID19 week by week. They are being sprayed by the patients. Once intubated, the doctors around the patients are less likely to catch the disease.
There are rare folks with mutations in the genes for cell receptors to which virus attaches who are resistant

6. Cats carry it, not so much dogs
It's not clear if you can get it from your cat.
Your dog, likely not a vector.

7. Hydroxychloroquine: 
Works by affecting the way endosomes inside cells which help kill virus. Likely there are other, unknown mechanisms of action as well.
Malaria can get resistant to this drug and the virus may well as well. If given at just the right time, this drug may make a difference and Dr. Daniel Griffin talks clearly about how ICU docs have learned to time the sequence of the drugs they give. They try to start it within the first 48 hours after symptoms begin.
Dr. Griffin mentioned he looked at the French study which suggested a great benefit for hydroxychloroquine and it was nothing more than a string of anecdotes woven together to suggest this is an effective drug.  Dr. Fauci called the study, "not robust" which was likely a generous description. Nevertheless, all COVID19 patients are now getting this + zithromycin on admission at some NYC hospitals. 

8. Masks:  used properly, may protect others against you and may protect you, in part by preventing you from getting your fingers in your nose or mouth. The TWIV guys admit they were less persuaded of the efficacy of masks in protecting against acquiring infection, but there are now some studies which suggest they can be effect not just to prevent spreading it to others but against acquiring it.

9. Mortality/ Prevalence: Because we do not have studies of the population for the presence of virus (current infection) or antibodies (past infection) we do not know.

10. How do you know if you've had it?  
Blood tests for antibodies are required. You can even tell how recently you have had it. If your IgM is negative and your IGG positive, you're probably 7-14 day past your innoculation.
Dr. Griffin

11. Daniel Griffin, MD who features in two of the key episodes on TWIV (#595 and #598) details exactly how the doctors have learned to treat this, correcting initial mistakes and capitalizing on what they have seen in their patients. Likely, your chances of dying if you get admitted to hospital are improved now because of what doctors have learned to do and not to do. But if you wind up on a respirator, your chances are only 50/50.

12. "Cytokine storm" :
Is what happens when your immune system starts carpet bombing your own body, trying to kill of the virus.

The best way to understand this is through an analogy to that episode from "Band of Brothers" in which Captain Winters has his platoon attack the Germans and they fire single shots mostly, some machine gun fire, and they shoot individual German soldiers.  In doing this, they kill only the enemy, and not their own troops. 

This is analogous to what is called "adaptive" immunity in biology. 
The B cells make specific antibodies to a specific virus and kill off the virions specifically, aiming at specific targets.

But then the artillery starts firing, and anyone in the vicinity gets blown to smithereens, the American shelling killing Americans and Germans indiscriminately. 
This is analogous to what is called "innate" immunity.  It involves things like IL6, cytokines, all sorts of stuff which just burns the village down, blows away Jeeps, troops, anything.

During the first 7 days of infection, the virus load increases and the patient is sick. 
At this point, antivirals like "Tosi" may help. This is when the B cells are trying to shoot the virions with antibodies.

But when the patient crashes, has trouble breathing and the chest X rays show fluid flooding the lungs, that is the "innate" system, the artillery, kicking in and the patient dies from the indiscriminant mayhem wrought by the innate system.

Doctors have learned to treat this with a variety of medications, including cortisone drugs, but also interferon.

You can google TWIV episode #598 or try this link:

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