# Covid infections declining worldwide **URL:** \ **Category:** The Quarantine Zone\ **Tags:** covid-quarantine\ **Created:** [February 17, 2021, 6:49pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153 "2021-02-17T18:49:49Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![SayTwo](https://avatars.discourse-cdn.com/v4/letter/s/e56c9b/32.png) [@SayTwo](https://boards.straightdope.com/u/SayTwo)\ **Post date:** [February 25, 2021, 5:54pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/21 "2021-02-25T17:54:02Z")
Could be warming weather. This virus may not like it when it’s too cold any more than it does when it’s too hot. Or at least, that would be an interesting hypothesis to explore. ---
**Author:** ![HughGoply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hughgoply/32/7834_2.png) [@HughGoply](https://boards.straightdope.com/u/HughGoply)\ **Post date:** [February 25, 2021, 6:33pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/22 "2021-02-25T18:33:34Z")
Except it’s been much colder in the Northern Hemisphere until about Sunday. ---
**Author:** ![filmore](https://avatars.discourse-cdn.com/v4/letter/f/7993a0/32.png) [@filmore](https://boards.straightdope.com/u/filmore)\ **Post date:** [February 25, 2021, 6:39pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/23 "2021-02-25T18:39:41Z")
Just a wild thought, but is there any change in cosmic activity that might explain it? Perhaps an increase in cosmic radiation, solar flares, or something similar might degrade the virus in some way. ---
**Author:** ![HughGoply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hughgoply/32/7834_2.png) [@HughGoply](https://boards.straightdope.com/u/HughGoply)\ **Post date:** [February 25, 2021, 6:44pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/24 "2021-02-25T18:44:30Z")
That would make sense. Since the vaccine is a microchip, the virus is probably at least part microchip. Microchips that aren’t insulated can be sensitive to cosmic radiation. ---
**Author:** ![filmore](https://avatars.discourse-cdn.com/v4/letter/f/7993a0/32.png) [@filmore](https://boards.straightdope.com/u/filmore)\ **Post date:** [February 25, 2021, 6:49pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/25 "2021-02-25T18:49:13Z")
That’s funny, but I didn’t mean it in that way. Cosmic radiation can damage DNA. It’s seems plausible that the DNA in the aerosolized virus particles might be damaged if there was increased radiation. ---
**Author:** ![susan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/susan/32/17537_2.png) [@susan](https://boards.straightdope.com/u/susan)\ **Post date:** [February 25, 2021, 6:56pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/26 "2021-02-25T18:56:13Z")
Nitpick: I believe COVID is RNA, not DNA. ---
**Author:** ![RitterSport](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rittersport/32/6326_2.png) [@RitterSport](https://boards.straightdope.com/u/RitterSport)\ **Post date:** [February 25, 2021, 6:57pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/27 "2021-02-25T18:57:24Z")
It’s not warming worldwide. Looking at the various graphs on [this](https://www.nytimes.com/interactive/2020/world/coronavirus-maps.html) page, it would be difficult to definitively say which countries are in the Southern vs. Northern hemisphere, and which countries are basically warm all the time. ---
**Author:** ![HughGoply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hughgoply/32/7834_2.png) [@HughGoply](https://boards.straightdope.com/u/HughGoply)\ **Post date:** [February 25, 2021, 8:11pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/28 "2021-02-25T20:11:32Z")
> [@filmore](#): > > That’s funny, but I didn’t mean it in that way. Cosmic radiation can damage DNA. It’s seems plausible that the DNA in the aerosolized virus particles might be damaged if there was increased radiation. I doubt cosmic radiation would have an effect, but maybe the increased sunlight in the Northern Hemisphere. ---
**Author:** ![Tzigone](https://avatars.discourse-cdn.com/v4/letter/t/839c29/32.png) [@Tzigone](https://boards.straightdope.com/u/Tzigone)\ **Post date:** [February 25, 2021, 8:27pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/29 "2021-02-25T20:27:14Z")
> [@Tfletch1](#): > > I think the world data trend looks like the US because we have such a large percentage of cases. At our highest point, the US was contributing about 40% of cases worldwide. If you look at different countries, the trends do vary. But when you at it by [another regional breakdown](https://www.cnn.com/2021/02/10/health/who-covid-global-cases-decline-intl/index.html), it’s still following the same trends, though the numbers aren’t identical, of course. Though that’s a couple weeks old, so it may look different now. ---
**Author:** ![Tfletch1](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tfletch1/32/5340_2.png) [@Tfletch1](https://boards.straightdope.com/u/Tfletch1)\ **Post date:** [February 25, 2021, 9:22pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/30 "2021-02-25T21:22:18Z")
> [@Tzigone](#): > > But when you at it by [another regional breakdown](https://www.cnn.com/2021/02/10/health/who-covid-global-cases-decline-intl/index.html), it’s still following the same trends, though the numbers aren’t identical, of course. Though that’s a couple weeks old, so it may look different now. I think this is a better [presentation](https://ichef.bbci.co.uk/news/976/cpsprodpb/D3A2/production/_117087145_optimised-2021-02-19-ecdc.timeseries.continents.cases.weekly.plot-nc.png). It shows each region separately. If you view each country separately, the trends are even more different. So, there’s a first surge in Spring; US, India, and Latin America had a Summer surge; Europe and America had huge Fall surges but months apart. Since the US was significantly involved in all three surges, the general shape of world cases, mirrors the US. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [February 25, 2021, 10:17pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/31 "2021-02-25T22:17:21Z")
USA! USA! We’re number ONE!! We’re number ONE!! 😉 ---
**Author:** ![penultima\_thule](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/penultima_thule/32/3833_2.png) [@penultima\_thule](https://boards.straightdope.com/u/penultima_thule)\ **Post date:** [February 25, 2021, 10:23pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/32 "2021-02-25T22:23:12Z")
> [@Tfletch1](#): > > I think this is a better presentation > Antarctica and Oceania cases excluded as too low to register on scale Yep, we are proved to be an absolute failure at this global pandemic business. ---
**Author:** ![Tzigone](https://avatars.discourse-cdn.com/v4/letter/t/839c29/32.png) [@Tzigone](https://boards.straightdope.com/u/Tzigone)\ **Post date:** [February 25, 2021, 11:24pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/33 "2021-02-25T23:24:37Z")
> [@Tfletch1](#): > > I think this is a better [presentation](https://ichef.bbci.co.uk/news/976/cpsprodpb/D3A2/production/_117087145_optimised-2021-02-19-ecdc.timeseries.continents.cases.weekly.plot-nc.png). It shows each region separately. If you view each country separately, the trends are even more different. So, there’s a first surge in Spring; US, India, and Latin America had a Summer surge; Europe and America had huge Fall surges but months apart. Since the US was significantly involved in all three surges, the general shape of world cases, mirrors the US. That’s informative, thanks. (Edited by @puzzlegal to fix formatting) ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [February 26, 2021, 4:14am UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/34 "2021-02-26T04:14:31Z")
If testing actually has only captured 1/5th of cases and there [really have 120 million cases in the US](https://www.npr.org/sections/health-shots/2021/02/06/964527835/why-the-pandemic-is-10-times-worse-than-you-think), and we’ve vaccinated 46 million people, we might be approaching herd immunity. ---
**Author:** ![mikecurtis](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mikecurtis/32/3284_2.png) [@mikecurtis](https://boards.straightdope.com/u/mikecurtis)\ **Post date:** [February 26, 2021, 10:15am UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/35 "2021-02-26T10:15:46Z")
Nope. The US population is ~330 million, so your numbers are just a little over 50%. HI doesn’t kick in until at least 80% Still a long way to go. Plus, it seems that immunity acquired through infection fades over time, so those infected at the beginning are unlikely to still have an immune response. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 26, 2021, 11:51am UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/36 "2021-02-26T11:51:00Z")
Herd immunity isn’t something that “kicks in” all at once. If 50% of the population is immune, then you’ll have 50% lower instantaneous infection rates. If the disease has an R0 of greater than 2, then that’ll leave it still in epidemic status, but it’s a lot better than the baseline. And that actually understates it, because you don’t have all the population mixing uniformly. Some subpopulations are, for various reasons, at higher risk of infection. Those subpopulations would account for more than their share of the people who have been infected so far, and their subsequent immunity would also have a greater part in reducing further cases. > [@mikecurtis](#): > > Plus, it seems that immunity acquired through infection fades over time, so those infected at the beginning are unlikely to still have an immune response. Everyone always says that this might be the case, but the only evidence anyone ever seems to produce that it is the case is citing a lot of people who say that it might be the case. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [February 26, 2021, 1:10pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/37 "2021-02-26T13:10:38Z")
That global decline shows signs of leveling off. In the past week, new cases have plateaued at about 400k cases a day. Too soon to say for sure, though. Similar plateau in the US, too, circa 70k cases a day now ---
**Author:** ![tofor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tofor/32/13727_2.png) [@tofor](https://boards.straightdope.com/u/tofor)\ **Post date:** [February 26, 2021, 4:35pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/38 "2021-02-26T16:35:06Z")
> [@Qadgop\_the\_Mercotan](#): > > Similar plateau in the US, too, circa 70k cases a day now The chart at [this link](http://91-divoc.com/pages/covid-visualization/?chart=states&highlight=Delaware&show=us-states&y=both&scale=linear&data=cases-daily-7&data-source=merged&xaxis=right-8wk#states) shows dramatic increases in Texas and mostly level or declining everywhere else. It looks like the wild improvement phase is over, unfortunately. ---
**Author:** ![mikecurtis](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mikecurtis/32/3284_2.png) [@mikecurtis](https://boards.straightdope.com/u/mikecurtis)\ **Post date:** [February 26, 2021, 7:13pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/39 "2021-02-26T19:13:20Z")
> [@Chronos](#): > > If the disease has an R0 of greater than 2, then that’ll leave it still in epidemic status, but it’s a lot better than the baseline. This is the point I was trying to make. The term “herd immunity” has a [specific definition](https://www.health.harvard.edu/diseases-and-conditions/preventing-the-spread-of-the-coronavirus) > Herd immunity occurs when enough people become immune to a disease to make its spread unlikely. As a result, the entire community is protected, even those who are not themselves immune. Herd immunity is usually achieved through vaccination, but it can also occur through natural infection. > [For Covid-19]Experts initially estimated that somewhere between 60% and 70% of the population needs to be immune in order to achieve herd immunity. More recently, they have raised that estimate to near 90%. (As of now, we are nowhere close to the numbers needed to achieve herd immunity.) > [@Chronos](#): > > Everyone always says that this might be the case, but the only evidence anyone ever seems to produce that it is the case is citing a lot of people who say that it might be the case. I did say it **seems** to be the case, and since we’re just a year into this pandemic, there are a dearth of studies but here’s one [https://www.nejm.org/doi/full/10.1056/NEJMc2025179](https://www.nejm.org/doi/full/10.1056/NEJMc2025179) > Given that early antibody decay after acute viral antigenic exposure is approximately exponential,3 we found antibody loss that was quicker than that reported for SARS-CoV-1,4,5 and our findings were more consistent with those of Long et al.1 Our findings raise concern that humoral immunity against SARS-CoV-2 may not be long lasting in persons with mild illness, who compose the majority of persons with Covid-19. It is difficult to extrapolate beyond our observation period of approximately 90 days because it is likely that the decay will decelerate.3 Still, the results call for caution regarding antibody-based “immunity passports,” herd immunity, and perhaps vaccine durability, especially in light of short-lived immunity against common human coronaviruses. Further studies will be needed to define a quantitative protection threshold and rate of decline of antiviral antibodies beyond 90 days. ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [February 26, 2021, 7:26pm UTC](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153/40 "2021-02-26T19:26:44Z")
> [@tofor](#): > > The chart at [this link](http://91-divoc.com/pages/covid-visualization/?chart=states&highlight=Delaware&show=us-states&y=both&scale=linear&data=cases-daily-7&data-source=merged&xaxis=right-8wk#states) shows dramatic increases in Texas and mostly level or declining everywhere else. It looks like the wild improvement phase is over, unfortunately. It’s only been about three weeks since the CDC begged people not to have Superbowl parties and were largely ignored - remember all the maskless idiots on the news? Maybe the plateau is due to that. If it drops again in a couple/three weeks, that’s where I’d lay blame. [Previous page](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153.md?page=1) [Next page](https://boards.straightdope.com/t/covid-infections-declining-worldwide/933153.md?page=3)