> And wherever we look, infections level off before 10%-20% of the population is infected. This is somewhat mysterious.<p>This is not really true.<p>Bergamo had a 58% infection rate as of last month: <a href="https://bergamo.corriere.it/notizie/cronaca/20_maggio_22/bergamo-test-sierologici-cittadini-583percento-positivo-un-giorno-51-contagi-piu-8f6ac032-9c44-11ea-aab2-c1d41bfb67c5.shtml" rel="nofollow">https://bergamo.corriere.it/notizie/cronaca/20_maggio_22/ber...</a><p>Several prisons have seen infection rates in the 70-80% range: <a href="https://www.npr.org/sections/coronavirus-live-updates/2020/04/20/838943211/73-of-inmates-at-an-ohio-prison-test-positive-for-coronavirus" rel="nofollow">https://www.npr.org/sections/coronavirus-live-updates/2020/0...</a><p>The USS Theodore Roosevelt had an infection rate of 60%: <a href="https://www.cdc.gov/mmwr/volumes/69/wr/mm6923e4.htm?s_cid=mm6923e4_e&amp;deliveryName=USCDC_921-DM30202" rel="nofollow">https://www.cdc.gov/mmwr/volumes/69/wr/mm6923e4.htm?s_cid=mm...</a><p>A better explanation for the leveling off is simply that social distancing and lockdowns have reduced the spread of the virus.
T cell responses are interesting. Infectolab (<a href="https://www.infectolab-americas.com/" rel="nofollow">https://www.infectolab-americas.com/</a>) and its originator Armin (Germany) are using T cell responses for tick borne diseases like: Borellia (Lyme), Bartonella and Babesia because antibody testing is difficult for these (broken via CDC specs as most labs won't test key proteins 31, 34 and never indicate which antibodies are present). Bartonella is very hard to test for with antibody and PCR. It really depends on lab specialty. The sars-cov-2 antibody tests are unpredictable in quality, so nearly useless (my dr is 0-50 via Quest and many people had + PCR).<p>In short, our immune context (genetic phenotype) is unique! We need a lot more data from everyone to start making accurate correlations. We do not measure T-cells, cytokines, mast cells, b-cells, HLA (partly how we potentially make antibodies) at any meaningful level to provide much confidence. Many natural/industrial substances suppress our T-cell responses and generally innate immune system (metals, mold toxins, etc), so we also need to start accounting for those.<p>It's a long road we have in front of us. Hopefully the medical system supports patient data ownership and research to improve on our obvious ignorance.
The author asks some questions which can be answered by gathering some data.<p>This suggests going back and re-testing for antibodies some populations from tightly packed groups - the cruise ship passengers, warship crew, and nursing home residents. The antibody tests are more accurate than they were two months ago. The key here is to find out how many people, definitely exposed to the virus, not only did not show any symptoms, but did not develop antibodies. That group presumably had some form of pre-existing immunity.<p>Is anybody doing something like that?
Kind of shows how little we know about the human immune system. Hopefully this pans out and we won’t see massive new waves. I have an anecdotal example of that this might be something. A friend and his wife got tested before delivering their baby and she was positive for antibodies and he was negative. He might have just beaten the virus before the body even started creating antibodies.
Highly recommend the companion series of podcasts to TWiV if this article perks your interest: <a href="https://www.microbe.tv/immune/" rel="nofollow">https://www.microbe.tv/immune/</a>
> Does this mean that if you recently had a Coronavirus that caused a head cold that you have a measure of protection?<p>Apparently, <i>no</i>, as there are no observed differences in the percentages of infected when the people who have children or work with children are compared with those who don't. If the stated assumption were true, those that were more exposed to other coronaviruses (which would be expected among those having or being close to kids) would be as a group less prone to be infected. That was apparently not observed.<p>So the "slowdowns" are just the humans adapting their behavior to reduce their chances of getting infected. When Rt is 1 the growth is linear, as simple as that. Less of such changes in the population behavior, more people are getting infected, faster.<p>Source: translated transcript of the podcast of Christian Drosten. Hint: also, don't believe what most of the media says that "he said" -- I've seen a lot of "editorialized" reporting of what he says, to the point of the end product being completely opposite of what he actually said. It's that bad. One really has to go to the source and read. Unfortunately, it's a lot of work, as the podcasts are long. So the people who don't read the source tend to have completely wrong idea what he actually said -- that's also why I'm not giving the specific link: if one doesn't invest really a lot of energy and find and carefully the sources, one has more chance to acquire completely wrong conclusions as "highlights."
This article talks about cell mediated immunity whereby compromised cells are detected via peptides produced, but there's actually another mechanism that's still in the early stages of being understood called merocytophagy where an immune cell can partially "eat" another cell to see if it "tastes" sick.
"It took nine days for the number of infections to grow from 6 million to 7 million, and less than eight days to get to the latest million, so the pandemic is not slowing down." <a href="https://www.abc.net.au/radio/programs/coronacast/the-global-hotspots-where-coronavirus-is-still-killing-thousands/12361280" rel="nofollow">https://www.abc.net.au/radio/programs/coronacast/the-global-...</a>
So... Does this mean that we can "self" vaccinate by going maskless and running around the city and in and out of grocery stores every few days?
I am mostly joking here, but I am also serious, the post implies that we can develop immunity by getting minor exposures over a period of time.
I read the article twice and probably need it twice more to fully understand it, but please enlighten me.
The amount of frustrations surrounding all of this is mind numbing. I almost expect we will get vaccinations before we get understanding.<p>And I share that call-out in this article that not knowing is not a claim that things aren't working. I just expand it as not a claim that some things have worked. We need more studies that will frustratingly take time.