General Course of the Pandemic
There is uniform agreement that at least twenty states are in an upward swing. It is unclear if most of the new cases are centered in prisons, meat packing plants, and nursing homes because there are states that are no longer making this information available. From my viewpoint it does not matter, because there are people who work in these facilities that go home at the end of their workday, and they carry with them whatever infection they have been exposed to. But there are people in the media who feel that a nursing home case should not be counted, because these people are not circulating among the rest of us. I think that this argument is flawed.
Worldwide, we have most European and Asian countries demonstrating a good grasp on the virus, even though victory cannot be declared (except New Zealand, that claims to be rid of it). Brazil has passed everyone except the US in total cases and deaths. Perú, which tried its best, has a serious problem anyway. The rest of the Americas are doing poorly and scheduled to do worse. Africa should be the next epicenter. It is clear that the virus is going nowhere.
Those who hoped that warm weather and outdoor exposure would help are a bit disappointed. Texas and Arizona are plenty warm this time of year, and they have the steepest curves.
There was another report, this time from the US, that maybe the virus had mutated and was not as dangerous anymore. Yes, the virus has mutated. One of these mutations had made it more infectious, not less. Maybe the reason that deaths as a percentage of infections has gone down is because we are testing more asymptomatic people, and we are much better at treating them if they get sick.
We are doing in the neighborhood of 500,000 tests per day. I have not been able to find any information as to whether these are PCR or antigen tests. Those people who figured that a positive antibody test would give them an “immunity passport” to go wherever they please have been disappointed. There is no proof; none; that a positive antibody test protects us from a new infection. Which is interesting, because every expert that I have read says that those people who had covid with symptoms are not getting sick again when re-exposed.
A lot written about the “asymptomatic” carriers. It has been the gospel so far that the reason that the virus spreads so fast is because many people who pass it on to others have no symptoms. This past week the WHO put out a bulletin that said that asymptomatic transmission was “rare.” Which goes against the prevailing gospel. It only took a day for retractions to come left and right. Now they say that there is a new category of infected people called “presymptomatic.” They say that while it is true that people without symptoms spread the virus, most of these people will have at least one tiny teensy weensy symptom if you sit on them, hold a baseball bat over their heads, and force them to confess to minimal loose bowels, or an itchy eye, or being a bit tired two days ago. This splitting of hairs is a bit disappointing coming from the WHO.
Hydroxychloroquine back in the news. The scientific papers that said that it was not effective, and that it may increase the chances of death, have been retracted. Retracting a paper that has been published in a prestigious journal is a very unusual and particularly humiliating step. It appears that both papers used information provided by an organization that has taken down its web site and is unable to explain where they got their numbers. This is one of the hazards that we encounter when there is a rush to get information out as soon as possible. The review process suffers. Today the FDA retracted its approval of hydroxychloroquine for covid-19 treatment anyway. There are many studies ongoing, and none has shown an early “signal” that it is effective. Do not take it.
No more news on oral treatments. We should have had some preliminary result by now if any of the candidate medicines had shown prompt cures.
Antibody treatments are back in a positive light. Before we go into the news, some explanations are needed.
For today’s purposes (and only for today), there are two kinds of antibodies that are developed in response to an infection. Binding antibodies, made by B lymphocytes (also known as B cells), stick to the infectious agent (virus or bacteria), but do not prevent this agent from attacking your cells. It is helpful, as we said weeks ago, to imagine the virus-antibody “mating” as a three-dimensional jigsaw puzzle. The antibody can attach (bind) to the tail of the virus, but if the virus does not use its tail to invade our cells, this antibody is not as helpful. It does help some, because when the binding takes place a host of immune cells are summoned, and they will ingest the virus and break it down IF it has not entered any cells yet.
Neutralizing antibodies stick to the part of the virus that the virus needs to get into our cells. In covid-19’s case this is called the “spike” protein. If there is antibody sticking to the spike, the spike is unable to attach itself to our cells. Our immune soldiers will soon find this invader with this huge protein sticking out of its crown. The invader has no chance.
Neutralizing antibodies are also made by B lymphocytes. Within hours of the manufacture of a neutralizing antibody, our bodies learn if this protein is of so-so efficacy, or if it is really powerful stuff. The so-so B cells are asked to kill themselves, and our bodies make billions of the best B cells. To be very correct about this, it is not B cells that end up making the bulk of neutralizing antibodies. The “winning” B cells turn into something called plasma cells, and it is them who generate the industrial amounts of good antibody. Just in case a doctor is reading this; I had to clarify.
Good neutralizing antibodies against COVID-19 have been hard to come by. The paper that I read today says that less than 5% of COVID-exposed people have been shown to make the premium stuff. Researchers at Stanford have been able to isolate one of these ultra-successful B cells. They have induced these cells to have trillions of babies; now they are harvesting good antibody from this mix.
How this COULD translate into practice: Getting an as of yet undetermined amount of this anti-COVID antibody could protect you from infection for weeks or months. Provided that the spike protein fails to mutate in any significant way. It would work as a vaccine, but instead of your immune system making its own antibody, you would get it ready-made, like a TV dinner. OK; that was an unappetizing simile. But you get it. Stay tuned.
Astra Zeneca announced today that all of the European Union will get its adenovirus (Oxford) vaccine; there will be no shortages. The US will also be provided for. Large-scale human testing will begin in September. I hope that the process will not be rushed because of commercial or political reasons. Other vaccines are on schedule.
For now, masks are still needed; keep washing your hands; read some poetry.