COVID-19: Do We Now Know the Asymptomatic %?

From Worldometer,  COVID-19 new deaths:

           DAY USA   WORLD   Brazil      India   South Africa

June      9     1093    4732        1185      246         82

July       1       676    4857        1057      438         92

             5       251    3572          535       421       173

             7       993    5504        1312       479       192

           12       380    4118          659       500       108

           14       935    5414        1341       586       174

           15     1001    5760        1261       614       107

           19       412    4606          715       675         85

           21     1119    5669        1346       671        195

           22     1205    7128        1293     1120        572

           26       450    4307         556       715        114
           28    1266     5589         955       776        190
Aug      1    1462     6429       1191       765        193
            2     1123     5601       1048       852        148
            3       467     4430         514       514        213

            5     1362     6292       1394       849        345

          10       534     4813         593     1013        198
          11       569     4575         721       887        213
          12     1504     6556       1242       835        130
          13     1386     6816       1164       950        129
          14     1284     6653       1301     1006        260
          15     1071     5410         726       950        121
          16       522     4525         582       961        162
          17       589     4289         775       880        143
          18     1358     6312        1365    1089        282
          19     1263     6671        1170      980        159
          20     1090     6188        1234      981        195
          21     1170     6062        1031      953        225

Summary:

• Not a good day.  However, it is more and more appearing that both the World and USA are on the downside of the peak for new cases.  
• If there is no next wave, deaths/day will begin to soon drop.  Not so for India and that region, nor for Africa.
• Some good news:
• The UK only experienced 2 new deaths and Germany, 4.
• China has now dropped to #34 in total cases, had 22 new cases and NO new deaths.
• Thailand, now #117 in total cases (and only around half that of the whole state of Hawaii, which is doing relatively well in the U.S.) had only one new case and no new deaths.

I thought I'd re-visit the mystery of asymptomatic COVID-19 cases because I'm in the midst of discussions related to this pandemic.  I focused on this asymptomatic matter earlier this month.  Read my analysis of 3 August 2020.  I was hoping that the field was homing in on better understanding this mystery.  Nope.   I just found the following to add to this bewilderment (as of 14 August 2020):

●In a COVID-19 outbreak on a cruise ship (Diamond Princess) where nearly all passengers and staff were screened for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), approximately 19 percent of the population on board tested positive; 58 percent of the 712 confirmed COVID-19 cases were asymptomatic at the time of diagnosis [14,15]. In studies of subsets of those asymptomatic individuals, who were hospitalized and monitored, approximately 77 to 89 percent remained asymptomatic over time [15,16].  My interpretation is that the 77%-89% range refers to the 58% who were shown to be asymptomatic.  Thus, the actual asymptomatic rate was 45%-52%.

●In a smaller COVID-19 outbreak within a skilled nursing facility, 27 of the 48 residents (56 percent) who had a positive screening test were asymptomatic at the time of diagnosis, but 24 of them ultimately developed symptoms over the next seven days [17]. Somewhat confusing, but I think the end result is that there were only 3 asymptomatic cases, meaning an asymptomatic rate of 6%.

●Other studies have reported even higher proportions of asymptomatic cases [10,18-20]. As an example, in a report of a universal screening program of pregnant women presenting for delivery at two New York hospitals at the height of the pandemic there, 29 of 210 asymptomatic women without fever (14 percent) had a positive SARS-CoV-2 reverse-transcription polymerase chain reaction (RT-PCR) test on a nasopharyngeal specimen [10]. Four additional women had fever or symptoms and also tested positive. Thus, of 33 women with a positive SARS-CoV-2 test, 29 (88 percent) were asymptomatic on presentation.  But nothing shared about the increase in later symptoms.

A 17 July 2020 release from the CDC indicates that the asymptomatic rate should be around 40%, and 75% of them could transmit this virus.  Further, asymptomatic children have a similar ability to transmit this disease to adults as anyone, making in-room school openings potentially dangerous, for they will bring the virus home.

However, on 10 August 2020, The Washington Post said:

A Boston homeless shelter had 147 infected residents, but 88 percent had no symptoms even though they shared their living space. A Tyson Foods poultry plant in Springdale, Ark., had 481 infections, and 95 percent were asymptomatic. Prisons in Arkansas, North Carolina, Ohio and Virginia counted 3,277 infected people, but 96 percent were asymptomatic.

The above expanded into the following :

As you can see, this is all very confusing.  The asymptomatic rate ranges from 6.3% to 94.6%  This virtually random spread must mean something important, except experts haven't quite figured out exactly what.  As of 22 August 2020, the medical field remains totally befuddled!

As colds and flus all come from a wide range of various viruses, including the coronavirus (which causes 20% of all colds--and I haven't yet been able to link any strain of coronavirus with the flu), I would think that the asymptomatic rate for the common cold should be in the 50% range of the flu.  Did you know that the cold is the leading reason for missing work?  In any case, in the past year or two many probably did get infected with a cold caused by some non-COVID-19 coronavirus strain.

As no one has yet provided any kind of sense to the above spread of asymptomatic cases, but that T-cells from previous common colds caused by some type of coronavirus might provide a clue, here are some thoughts:

• Those very high asymptomatic rates found with the homeless (87.8%), in prisons (96%) and chicken factories (94.6%) are because these individuals live in an environment where they get more colds.  If this ailment came from a coronavirus, their T-cells recognize and provide a kind of immunity from symptoms.  Maybe enough to cause asymptomaticity.
• People in nursing facilities are so well-protected that they have tended to avoid colds.  Plus, the incidence of colds does drop as you get older.  Thus older people  have a lower amount of pre-immunity, with more pre-conditions.  Thus, the asymptomatic rate is lower.
• Pregnant mothers must have a history of more colds/flus because they're closer to children, who seem  regularly sick from something.  The range is wide, but we average from 2-5 colds/year.  And these do not count asymptomatic cases.
• About cruise ships, there are too many conflicting factors to try to explain why the asymptomatic rate was 46.5% on the Diamond Princess and 81.3% on the Argentine ship.

If I had to blame anyone for this state of affairs, I select President Donald Trump.  He hates the thought of testing, which is why he did not invoke the Defense Production Act six months ago for the nation to develop a quick test kit.  Without sufficient tests, you're operating in the dark because of those asymptomatic cases.

Without sufficient testing, contact tracing is useless if the only individuals you trace are linked to a person who is symptomatic, which is currently the dominant mode of follow-up.  Six months into this pandemic, the U.S. has tested 23% of our population.  The Hawaii rate is 11%.  Of course, this percentage is actually lower because those who got infected certainly got more than one test.

In most parts of the nation, and certainly in Hawaii (which is in the bottom ten states with the lowest tests/capita--Colorado and Pennsylvania are the lowest), you essentially cannot get a COVID-19 test unless you show symptoms or were personally in close contact to an infected individual.  I live in an assisted living community, where we learned that a nurse tested positive.  But I can't get a test, unless I pay $120, because she hasn't identified me as a person who got close to her.  While I can appreciate the protection of personal identity, something is wrong with the reality, for if I know who she is, I can better remember whether she took my temperature a week ago, or whatever.

Further, it would be pointless for just me to pay that fee and get tested.  EVERY RESIDENT should be required to take that test so we all know we are all safe.  The factor of asymptomatic individuals needs to be underscored here.  Then this should be repeated weekly until the pandemic is over.  In any case, because of Trump, there aren't enough test kits available anyway.  Plus, who wants to pay $120 every time you do this?  Insurance companies?  A lot of people won't qualify.

So the bottom line is that we are in an impossible dilemma because of President Trump.  An assisted-living center is a potentially dangerous place to live these days.  Worse, there is nothing much the community administration can do except remain optimistic, diligent and careful.  Nothing I can do, but wear a mask, keep socially distant and be responsibly smart.  Hopefully we do not become an epicenter and an effective vaccine is quickly developed.

So we are faced with half the coronavirus cases mostly wandering about innocently infecting people.  Yet, I am optimistic that this pandemic will soon begin to decline because more people are using masks and some kind of herd immunity is beginning to take hold in badly infected areas.  Most schools have figured out a way to teach remotely and large audiences are now forbidden.  It might take years, but the economy will begin to return.  Hopefully November 3 will end the terrible reign of Donald Trump, although you can't help but worry about what he will do from that date till 20 January 2021.

For those who have come this far, some of you complain about your tough job.  Well, would you rather do this:

There are two ocean storms heading for the Gulf of Mexico, potential Hurricane Laura in the general direction of New Orleans and potential Hurricane Marco for Houston.

A few models have their eye crossing paths, with Laura then going to Houston and Marco to New Orleans.

Then, there is the possibility that they could combine into one larger hurricane.  If, by some chance they do run into each other, there is something called the Fujiwhara effect I explained more than ten years ago in the Pacific Ocean.  If Laura and Marco interact as hurricanes, that would be the first time this would happen in the Gulf.  What a worrisome year, for this is the earliest in history that an M-storm has occurred in the Atlantic/Gulf.

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