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Dr Louis P Coates
10 hrs ·
Coronavirus Update 5/12/2020 - BTHO COVID-19

So today at the time of this writing there are 18.196 new cases today with 1008 deaths. Cases and deaths still are significantly down to lowest levels in a long time. Today the mortality rate is at 5.54%. We also have 16,514 in critical condition still high so the fatality numbers will likely stay high a while longer. So the overall mortality rate dropped a little to 5.90%.

We also have now had 262,225 people recovered from this virus and should now have some degree of immunity from this horrific disease.

Locally, in Texas we are still plateaued and we are waiting for the downside of the curve. We had 1155 new cases and 26 new deaths with a slightly decreasing mortality rate of 2.7%.

Because antibody testing is being added to the numbers we are monitoring active cases. So we have 17,624, barely up from 17,142 active cases in Texas. The number of active cases has leveled off around 17k over the past 3 days. In addition we have 21,814 recovered now. So active cases are very stable. We are still many times under both the number of hospital beds and ICU beds needed.

Today in Dallas county 253 new cases and 2 new deaths. Harris county with 298 new cases and 7 new deaths. Collin county with 31 new cases and 1 new death. Denton county with 8 new cases and no new deaths. Tarrant county with 485 new cases and 2 new deaths. Brazos county with 9 new cases and no new deaths. Travis county with 44 new cases and 5 new deaths. Fort Bend county with 15 new cases and 2 new deaths. Also Bexar county with 66 new cases and 0 new deaths.

For the newbies we are predicting an overall fatality rate somewhere in the 0.3 to 0.7 range when we finally correct the denominator. The real question is just how much of the population is already infected 2%, 5%, 10% etc.

We have discussed it before but frequently asked, can people who had COVID-19 get re-infected?

In order to determine this we infected 4 rhesus monkeys with the SARS-COV2 virus and measured viral loads of SARS-COV2 with nasal and anal swabs which peaked around 3 days after initial infection. Then 1 monkey was destroyed to see what all parts of the body contained the virus Then after recovery they measured viral loads, when negative at 28 days they reinfected the 3 monkeys and found they showed no physical or radiological signs of infection. In addition they are tested again with nasal and anal swabs and they all had negative viral loads. So this is extremely promising showing that we will very likely develop immunity to the virus. So this states that those that have had symptomatic infections of Covid-19 will likely have some form of immunity from reinfection of the SARS-COV2 virus. This is the basis for developing a vaccine! No immunity, essentially means no vaccine. For those of you who are wanting human testing on immunity they are not going to purposely try to reinfect humans simply to test immunity. But people with symptomatic Covid-19 infections that tested positive and get reinfected will be the only way we can assess in humans.

https://www.biorxiv.org/content/10.1101/2020.03.13.990226v1

The real questions now are how long will the immunity last?

A month, a few months, a year, 2 years, 5 years, or even lifelong we simply don’t know. Also if you test positive for the SARS-COV\2 IgG do you have immunity while we think so, this we don’t know. What if the IgG is positive from a cross reaction to other coronavirus? What if it is a false positive from the test itself? Also what if you were asymptomatic will you mount a strong enough immune response to have any immunity from reinfection while we believe so we simply don’t know at this time. So we need further testing which is currently underway before any long term statements on immunity can be made.

Researchers at Mount Sinai who are currently enrolling 15,000 patients for plasma donation, so far they have tested 624 people so far and only 511 had high levels of antibodies, 42 had low levels and 71 had none initially but 64 were found to have weak antibodies a week later. So this brings into question if people who were asymptomatic initially will mount a strong enough response to have any immunity to a recurrent infection.

https://gabio.org/after-recovery-from-the-coronavirus-most…/

Also what if the virus mutates?

Well luckily historically the coronavirus is a slow mutating virus. With only minor mutations that usually do not affect our antibodies ability to bind the M or S (spike) proteins which are the antigens on the virus. If you remember from our immunology blog a month or so ago we those are where the antibodies bind to the virus to either inactivate or destroy the virus. These are also how the virus binds to and gets into our cells. So a mutation here could be very dangerous. FIrst it could make our antibodies unable to attach to the virus. Secondly, it could enhance the virus’s ability to infect our cells. Lastly, and hopefully, it could disable the viruses ability to infect our cells.

Unfortunately we actually did recently see a small mutation in the S (spike) protein so this is definitely not good news. The implication of this mutation is currently being studied. I am not a biochemist or virologist but if these types of mutations continue this could provide difficulty in developing a reliable vaccine and make people susceptible to a second infection if their antibodies do not recognize the S (spike) protein. So let’s hope we don’t see anymore of these types of mutations.

https://www.biorxiv.org/…/10.1…/2020.04.29.069054v1.full.pdf