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COVID-19 is an infectious disease caused by the SARS-CoV-2 virus, typically yielding varying levels of short- and long-term symptoms, including fever, cough, shortness of breath, loss of taste or smell, headaches, fatigue, joint pain, chest pain, heart palpitations, brain fog, and mood changes.<ref name="CDCSymptoms20">{{cite web |url=https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/symptoms.html |title=Symptoms of Coronavirus |author=Centers for Disease Control and Preventions |publisher=Centers for Disease Control and Preventions |date=22 February 2021 |accessdate=06 September 2021}}</ref><ref name="CDCLong20">{{cite web |url=https://www.cdc.gov/coronavirus/2019-ncov/long-term-effects.html |title=Long-Term Effects of COVID-19 |author=Centers for Disease Control and Preventions |publisher=Centers for Disease Control and Preventions |date=12 July 2021 |accessdate=06 September 2021}}</ref> A majority of cases yield relatively mild symptoms, but some progress to life-threatening short- and long-term situations involving pneumonia, organ failure, cardiovascular complications, renal complications, neurological complications, and psychiatric issues.<ref name="CDCLong20" /><ref name="WadmanHowDoes20">{{cite web |url=https://www.science.org/news/2020/04/how-does-coronavirus-kill-clinicians-trace-ferocious-rampage-through-body-brain-toes |title=How does coronavirus kill? Clinicians trace a ferocious rampage through the body, from brain to toes |work=Science |author=Wadman, M.; Couzin-Frankel, J.; Kaiser, J. et al. |doi=10.1126/science.abc3208 |date=17 April 2020 |accessdate=06 September 2021}}</ref><ref name="CCDCTheEpid20">{{cite journal |title=The epidemiological characteristics of an outbreak of 2019 novel coronavirus diseases (COVID-19) in China |journal=Chinese Journal of Epidemiology |author=Chinese Center for Disease Control and Prevention |volume=41 |issue=2 |pages=145–51 |year=2020 |doi=10.3760/cma.j.issn.0254-6450.2020.02.003 |pmid=32064853}}</ref><ref name="ElezkurtajCauses21">{{cite journal |title=Causes of death and comorbidities in hospitalized patients with COVID-19 |journal=Scientific Reports |author=Elezkurtaj, S.; Greuel, S.; Ihlow, J. et al. |volume=11 |at=4263 |year=2021 |doi=10.1038/s41598-021-82862-5 |pmid=33608563 |pmc=PMC7895917}}</ref><ref name="TaquetSixMonth21">{{cite journal |title=6-month neurological and psychiatric outcomes in 236 379 survivors of COVID-19: A retrospective cohort study using electronic health records |journal=The Lancet Psychiatry |author=Taquet, M.; Geddes, J.R.; Husain, M. et al. |volume=8 |issue=5 |pages=416–27 |year=2021 |doi=10.1016/S2215-0366(21)00084-5 |pmid=33836148 |pmc=PMC8023694}}</ref>
[[File:Fig1 Li JofPharmAnal2020 10-2.jpg|right|thumb|650px|The graphical abstract from [https://doi.org/10.1016/j.jpha.2020.03.001 Li ''et al.'' 2020], showing general features of SARS-CoV-2, current knowledge of molecular immune pathogenesis, and diagnosis methods of COVID-19 based on present understanding of SARS-CoV and MERS-CoV viral infections]]COVID-19 has presented numerous societal challenges, from supply line interruptions and economic sagging to overwhelmed healthcare systems and civil disorder. However, these are largely the social, economic, and political ripple effects of a disease that has brought with it a set of inherent attributes that make it more difficult to manage in human populations than say the flu.  


The first known case of COVID-19 dates back to November 2019, "according to government data seen by the ''South China Morning Post''"<ref name="MaCorona20">{{cite web |url=https://www.scmp.com/news/china/society/article/3074991/coronavirus-chinas-first-confirmed-covid-19-case-traced-back |title=Coronavirus: China’s first confirmed Covid-19 case traced back to November 17 |author=Ma, J. |work=South China Morning Post |date=13 March 2020 |accessdate=31 March 2020}}</ref>, though additional research has suggested an even earlier timeline. A non-peer-reviewed report released by Harvard Medical School in June 2020 suggested that circumstantial evidence of higher traffic around hospitals even a month earlier may push the Wuhan timeline back further.<ref name="FolmerSat20">{{cite web |url=https://abcnews.go.com/International/satellite-data-suggests-coronavirus-hit-china-earlier-researchers/story?id=71123270 |title=Satellite data suggests coronavirus may have hit China earlier: Researchers |author=Folmer, K.; Margolin. J. |work=ABC News |date=08 June 2020 |accessdate=07 July 2020}}</ref> Stories of routinely analyzed wastewater samples from locations in Brazil<ref name="ChenEarlier20">{{cite web |url=https://www.scmp.com/news/world/americas/article/3091757/earlier-signs-coronavirus-sewage-samples-brazil |title=‘Earlier signs of coronavirus’ in sewage samples in Brazil |author=Chen, S. |work=South China Morning Post |date=03 July 2020 |accessdate=07 July 2020}}</ref> and Italy<ref name="KellandItaly20">{{cite web |url=https://www.reuters.com/article/us-health-coronavirus-italy-sewage/italy-sewage-study-suggests-covid-19-was-there-in-december-2019-idUSKBN23Q1J9 |title=Italy sewage study suggests COVID-19 was there in December 2019 |author=Kelland, K. |work=Reuters |date=19 June 2020 |accessdate=07 July 2020}}</ref> may likewise indicate that the SARS-CoV-2 virus was circulating earlier than initially gauged. And June 2021 peer-reviewed research by Roberts ''et al.'' suggests the possibility of COVID-19 beginning to spread as early as early October.<ref name="RobertsDating21">{{cite journal |title=Dating first cases of COVID-19 |journal=PLoS Pathogens |author=Roberts, D.L.; Rossman, J.S.; Jarić, I. |volume=17 |issue=6 |at=e1009620 |year=2021 |doi=10.1371/journal.ppat.1009620 |pmid=34166465 |pmc=PMC8224943}}</ref>  
However, COVID-19 is not the flu, and it is indeed worse in its effects than the flu, contrary to many people's perceptions. Yes, COVID-19 and the flu have some symptom overlap. Yes, COVID-19 and the flu have some transmission type overlap. But from there it diverges. COVID-19 and SARS-CoV-2 is different in that it is more prone to be transmitted to others during the presymptomatic phase. And the body of evidence has grown since early on in the pandemic<ref name="AchenbachStudies20">{{cite web |url=https://www.washingtonpost.com/health/2020/04/29/studies-leave-question-airborne-coronavirus-transmission-unanswered/ |title=Studies leave question of ‘airborne’ coronavirus transmission unanswered |author=Achenach, J.; Johnson, C.Y. |work=The Washington Post |date=29 April 2020 |accessdate=01 May 2020}}</ref> that SARS-CoV-2 is transmittable predominately via an airborne route<ref name="VanBeusekomGlobal20">{{cite web |url=https://www.cidrap.umn.edu/news-perspective/2020/07/global-experts-ignoring-airborne-covid-spread-risky |title=Global experts: Ignoring airborne COVID spread risky |author=Van Beusekom, M. |work=Center for Infectious Disease Research and Policy |publisher=University of Minnesota |date=06 July 2020 |accessdate=07 July 2020}}</ref><ref name="DucharmeTheWHO20">{{cite web |url=https://time.com/5863220/airborne-coronavirus-transmission/ |title=The WHO Says Airborne Coronavirus Transmission Isn't a Big Risk. Scientists Are Pushing Back |author=Ducharme, J. |work=Time |date=07 July 2020 |accessdate=07 July 2020}}</ref><ref name="PennCOVID20">{{cite web |url=https://www.pennmedicine.org/updates/blogs/penn-physician-blog/2020/august/airborne-droplet-debate-article |title=COVID-19 Transmission: Droplet or Airborne? Penn Medicine Epidemiologists Issue Statement |author=Penn Medicine |work=Penn Physician Blog |date=02 August 2020 |accessdate=23 August 2020}}</ref><ref name="GreenhalghTen21">{{cite journal |title=Ten scientific reasons in support of airborne transmission of SARS-CoV-2 |journal=Lancet |author=Greenhalgh, T.; Jimenez, J.L.; Prather, K.A. et al. |volume=397 |issue=10285 |pages=1603–5 |year=2021 |doi=10.1016/S0140-6736(21)00869-2 |pmid=33865497 |pmc=PMC8049599}}</ref>, though transmission from contaminated surfaced or physical intimacy are also believed possible.<ref name="CDCScienceBrief21">{{cite web |url=https://www.cdc.gov/coronavirus/2019-ncov/more/science-and-research/surface-transmission.html |title=Science Brief: SARS-CoV-2 and Surface (Fomite) Transmission for Indoor Community Environments |publisher=Centers for Disease Control and Prevention |date=05 April 2021 |accessdate=06 September 2021}}</ref><ref name="WinterVerifyYes21">{{cite web |url=https://www.wusa9.com/article/news/verify/yes-vaccinated-people-can-transmit-covid-through-kissing/536-00d88093-498c-4e58-9db6-331a69618248 |title=VERIFY: Yes, vaccinated people can transmit COVID-19 through kissing |author=Winter, E.; Datil, A. |work=WUSA9 - Verify |date=27 May 2021 |accessdate=06 September 2021}}</ref> Hospitalization rates are higher, perhaps up to 10 times higher than the flu, and hospital stays are longer with COVID-19. People are dying more often from COVID-19 too, up to 10 times more often than people stricken with the flu.<ref name="HuangHow20">{{cite web |url=https://www.npr.org/sections/goatsandsoda/2020/03/20/815408287/how-the-novel-coronavirus-and-the-flu-are-alike-and-different |title=How The Novel Coronavirus And The Flu Are Alike ... And Different |author=Huang, P. |work=NPR: Goats and Soda |date=20 March 2020 |accessdate=01 April 2020}}</ref><ref name="ResnickWhy20">{{cite web |url=https://www.vox.com/science-and-health/2020/3/18/21184992/coronavirus-covid-19-flu-comparison-chart |title=Why Covid-19 is worse than the flu, in one chart |author=Resnick, B.; Animashaun, C. |work=Vox |date=18 March 2020 |accessdate=01 April 2020}}</ref><ref name="KumarCOVID20">{{cite web |url=https://abcnews.go.com/Health/covid-19-compared-flu-experts-wrong/story?id=69779116 |title=COVID-19 has been compared to the flu. Experts say that's wrong |author=Kumar, V. |work=ABC News |date=27 March 2020 |accessdate=01 April 2020}}</ref> And while flu vaccines are largely the norm around the world, and COVID-19 vaccines are gradually becoming more available, those who willing choose to not get the vaccine have a massively higher chance of dying from COVID-19 (as of August 2021, more than 99 percent of all deaths from COVID-19 are found with the unvaccinated<ref name="MostMyths21">{{cite web |url=https://www.bu.edu/articles/2021/myths-vs-facts-covid-19-vaccine/ |title=Myths vs. Facts: Making Sense of COVID-19 Vaccine Misinformation |author=Most, D. |work=The Brink |date=13 August 2021 |accessdate=06 September 2021}}</ref>, compared to some 80% of children who die from the flu while unvaccinated<ref name="USAFacts61000_21">{{cite web |url=https://usafacts.org/articles/how-many-people-die-flu/ |title=61,000 people died in the worst flu season of the past decade. COVID-19 has killed eight times that many |publisher=USAFacts |date=29 July 2021 |accessdate=06 September 2021}}</ref>).


By the middle of December, infections were at 27, and by the end of the year the number was 266.<ref name="MaCorona20" /> By that time, Chinese health authorities had been updated that the pneumonia-like symptoms of patients in China's Hubei province may have been the symptoms of a disease caused by a novel (new) coronavirus<ref name="MaCorona20" />, and the WHO was notified.<ref name="HuiTheCont20">{{cite journal |title=The continuing 2019-nCoV epidemic threat of novel coronaviruses to global health—The latest 2019 novel coronavirus outbreak in Wuhan, China |journal=International Journal of Infectious Diseases |author=Hui, D.S.; Azhar, E.I.; Madani, T.A. et al. |volume=91 |pages=264–66 |year=2020 |doi=10.1016/j.ijid.2020.01.009 |pmid=31953166}}</ref> At the start of 2020, that number grew to 381 known cases<ref name="MaCorona20" />, jumping to more than 7,700 confirmed and 12,000 suspected cases by the end of January.<ref name="WHOStatement20">{{cite web |url=https://www.who.int/news/item/30-01-2020-statement-on-the-second-meeting-of-the-international-health-regulations-(2005)-emergency-committee-regarding-the-outbreak-of-novel-coronavirus-(2019-ncov) |title=Statement on the second meeting of the International Health Regulations (2005) Emergency Committee regarding the outbreak of novel coronavirus (2019-nCoV) |author=World Health Organization |publisher=World Health Organization |date=30 January 2020 |accessdate=06 September 2021}}</ref> By that time, the WHO had convened a second meeting of its Emergency Committee to discuss the declaration of a PHEIC, saying the then-called "2019-nCoV" constituted a health emergency of international concern.<ref name="WHOStatement20" /> This spurred the publishing of WHO technical advice to other countries, with a focus on "reducing human infection, prevention of secondary transmission and international spread, and contributing to the international response."<ref name="WHOStatement20" /> However, at the same time, the virus was already beginning to spread in locations such as Australia<ref name="HuntFirst20">{{cite web |url=https://www.health.gov.au/ministers/the-hon-greg-hunt-mp/media/first-confirmed-case-of-novel-coronavirus-in-australia |title=First confirmed case of novel coronavirus in Australia |author=Hunt, G. |publisher=Australian Department of Health |date=25 January 2020 |accessdate=31 March 2020}}</ref>, France<ref name="JacobCorona20">{{cite web |url=https://www.lefigaro.fr/sciences/coronavirus-trois-premiers-cas-confirmes-en-france-20200124 |title=Coronavirus: trois premiers cas confirmés en France, deux d’entre eux vont bien |author=Jacob, E. |work=Le Figaro |date=24 January 2020 |accessdate=31 March 2020}}</ref>, Germany<ref name="SPIEGELBayer20">{{cite web |url=https://www.spiegel.de/wissenschaft/medizin/corona-virus-erster-fall-in-deutschland-bestaetigt-a-19843b8d-8694-451f-baf7-0189d3356f99 |title=Bayerische Behörden bestätigen ersten Fall in Deutschland |author=Der Spiegel |date=28 January 2020 |accessdate=31 March 2020}}</ref> Italy<ref name="SevergniniCorona20">{{cite web |url=https://www.corriere.it/cronache/20_gennaio_30/coronavirus-italia-corona-9d6dc436-4343-11ea-bdc8-faf1f56f19b7.shtml |title=Coronavirus, primi due casi in Italia «Sono due cinesi in vacanza a Roma» Sono arrivati a Milano il 23 gennaio |author=Severgnini, C. |work=Corriere della Sera |date=30 January 2020 |accessdate=31 March 2020}}</ref>, Japan<ref name="SimJapan20">{{cite web |url=https://www.straitstimes.com/asia/east-asia/japan-confirms-first-case-of-infection-with-new-china-coronavirus |title=Japan confirms first case of infection from Wuhan coronavirus; Vietnam quarantines two tourists |author=Sim, W. |work=The Straits Times |date=16 January 2020 |accessdate=31 March 2020}}</ref>, South Korea<ref name="Jin-wooConfirmation20">{{cite web |url=https://www.mk.co.kr/news/society/view/2020/01/80017/ |title=신종 코로나바이러스 한국인 첫환자 확인 |author=Jin-woo, S. |work=Maekyung.com |date=24 January 2020 |accessdate=31 March 2020}}</ref>, Spain<ref name="LindeSanidad20">{{cite web |url=https://elpais.com/sociedad/2020/01/31/actualidad/1580509404_469734.html |title=Sanidad confirma en La Gomera el primer caso de coronavirus en España |author=Linde, P. |work=El País |date=31 January 2020 |accessdate=31 March 2020}}</ref>, the United Kingdom<ref name="BallHunt20">{{cite web |url=https://www.thetimes.co.uk/article/hunt-for-contacts-of-coronavirus-stricken-pair-in-york-dh363qf8k |title=Hunt for contacts of coronavirus-stricken pair in York |author=Ball, T.; Wace, C. |work=The Times |date=31 January 2020 |accessdate=31 March 2020}}</ref>, and the United States.<ref name="HolshueFirst20">{{cite journal |title=First Case of 2019 Novel Coronavirus in the United States |journal=New England Journal of Medicine |author=Holshue, M.L.; DeBolt, C.; Lindquist, S. et al. |volume=382 |issue=10 |pages=929–36 |year=2020 |doi=10.1056/NEJMoa2001191 |pmid=32004427}}</ref>
Other aspects of the disease that make it difficult to manage include:


As the disease continued to spread in February 2020, naming conventions came together, with the WHO declaring the disease's name "COVID-19," short for "coronavirus disease 2019."<ref name="EnserinkUpdate20">{{cite web |url=https://www.science.org/news/2020/02/bit-chaotic-christening-new-coronavirus-and-its-disease-name-create-confusion |title=Update: ‘A bit chaotic.’ Christening of new coronavirus and its disease name create confusion |author=Enserink, M. |work=Science |date=12 February 2020 |accessdate=06 September 2021}}</ref><ref name="JiangADistinct20">{{cite journal |title=A distinct name is needed for the new coronavirus |journal=The Lancet |author=Jiang, S.; Shi, Z.; Shu, Y. et al. |volume=395 |issue=10228 |page=949 |year=2020 |doi=10.1016/S0140-6736(20)30419-0 |pmid=32087125}}</ref> By the end of the month, the WHO warned a "very high" likelihood the virus's spread could turn into a full [[pandemic]].<ref name="MulierWHO20">{{cite web |url=https://www.bloomberg.com/news/articles/2020-02-28/who-raises-global-risk-for-coronavirus-to-very-high-from-high |title=WHO Raises Global Risk for Coronavirus to Very High |author=Mulier, T. |work=Bloomberg |date=28 February 2020 |accessdate=31 March 2020}}</ref> Less than two weeks later, on March 11, 2020, the WHO declared the outbreak of SARS-CoV-2 a pandemic, noting more than 118,000 confirmed cases and 4,000 deaths on all continents except Antarctica.<ref name="GumbrechtWho20">{{cite web |url=https://www.cnn.com/2020/03/11/health/coronavirus-pandemic-world-health-organization/index.html |title=WHO declares novel coronavirus outbreak a pandemic |author=Gumbrecht, J.; Howard, J. |work=CNN Health |date=11 March 2020 |accessdate=31 March 2020}}</ref> By November 2020, the pandemic had become more serious, in the U.S. in particular; hospitals became overwhelmed—the most recorded COVID-19 hospitalizations since the pandemic started<ref name="DallUSHits20">{{cite web |url=https://www.cidrap.umn.edu/news-perspective/2020/11/us-hits-record-covid-19-hospital-cases |title=US hits record for COVID-19 hospital cases |author=Dall, C. |work=CIDRAP News |publisher=Center for Infectious Disease Research and Policy - University of Minnesota |date=11 November 2020 |accessdate=12 November 2020}}</ref>—and the pandemic became "a humanitarian crisis."<ref name="MaxourisAsTheHoli20">{{cite web |url=https://www.cnn.com/2020/11/12/health/us-coronavirus-thursday/index.html |title=As the holidays get closer, Covid-19 hospitalizations and deaths are happening at a faster rate |author=Maxouris, C. |work=CNN Health |date=12 November 2020 |accessdate=12 November 2020}}</ref> The U.S. FDA issued its first and second Emergency Use Authorization (EUA) for a COVID-19 vaccine, the Pfizer-BioNTech COVID-19 Vaccine<ref name="FDATakesKey20">{{cite web |url=https://www.fda.gov/news-events/press-announcements/fda-takes-key-action-fight-against-covid-19-issuing-emergency-use-authorization-first-covid-19 |title=FDA Takes Key Action in Fight Against COVID-19 By Issuing Emergency Use Authorization for First COVID-19 Vaccine |publisher=U.S. Food and Drug Administration |date=11 December 2020 |accessdate=06 September 2021}}</ref> and Moderna COVID-19 Vaccine<ref name="FDATakesAdd20">{{cite web |url=https://www.fda.gov/news-events/press-announcements/fda-takes-additional-action-fight-against-covid-19-issuing-emergency-use-authorization-second-covid |title=FDA Takes Additional Action in Fight Against COVID-19 By Issuing Emergency Use Authorization for Second COVID-19 Vaccine |publisher=U.S. Food and Drug Administration |date=18 December 2020 |accessdate=06 September 2021}}</ref>, in December 2020, giving hope that a much wider vaccine roll-out would happen by late winter and early spring of 2021 in the U.S.<ref name="ThomasVacc21">{{cite web |url=https://www.nytimes.com/2021/02/03/health/covid-vaccines.html |title=Vaccine News Gives Hope for Spring, if Enough People Get the Shots |author=Thomas, K.; Robbins, R. |work=The New York Times |date=03 February 2021 |accessdate=06 September 2021}}</ref> However, concerns that wealthier residents and countries would largely lead the charge while leaving poorer residents and countries behind were heavily vocalized.<ref name="ThomasVacc21" /><ref name="BaharRich21">{{cite web |url=https://www.brookings.edu/blog/up-front/2021/02/11/rich-countries-have-a-moral-obligation-to-help-poor-countries-get-vaccines-but-catastrophic-scenarios-are-overrated/ |title=Rich countries have a moral obligation to help poor countries get vaccines, but catastrophic scenarios are overrated |author=Bahar, D. |work=Brookings |date=11 February 2021 |accessdate=06 September 2021}}</ref>
* ''Median incubation period'': According to research published in ''Annals of Internal Medicine'', the median (i.e., the central tendency, which is less skewed than average<ref name="NRCSMedian">{{cite web |url=https://www.wcc.nrcs.usda.gov/normals/median_average.htm |title=Median vs. Average to Describe Normal |author=National Water and Climate Center |publisher=U.S. Department of Agriculture |accessdate=01 April 2020}}</ref>) incubation period is 5.1 days (Note that as new variants arrive, incubation times my change; the delta variant is thought to have an incubation period of four days, for example.<ref name="KochvarDelta21">{{cite web |url=https://www.nch.org/news/delta-variant-questions-answered/ |title=Delta variant questions answered |author=Kochvar, G.; Shah, A. |publisher=Northwest Community Healthcare |date=16 August 2021 |accessdate=06 September 2021}}</ref>), with 97.5% of symptomatic carriers showing symptoms within 11.5 days. The authors found this to be compatible with U.S. government recommendations of monitored 14-day self-quarantines if individuals were at risk of exposure.<ref name="LauerTheInc20">{{cite journal |title=The Incubation Period of Coronavirus Disease 2019 (COVID-19) From Publicly Reported Confirmed Cases: Estimation and Application |journal=Annals of Internal Medicine |author=Lauer, S.A.; Grantz, K.H.; Bi, Q. et al. |year=2020 |doi=10.7326/M20-0504 |pmid=32150748 |pmc=PMC7081172}}</ref> However, many people continue to not take mask-wearing—and vaccination—seriously, and thus unmasked presymptomatic (and asymptomatic) carriers are thus largely more prone to spreading the virus.<ref name="MandavilliInfected20">{{cite web |url=https://www.nytimes.com/2020/03/31/health/coronavirus-asymptomatic-transmission.html |title=Infected but Feeling Fine: The Unwitting Coronavirus Spreaders |author=Mandavilli, A. |work=The New York Times |date=31 March 2020 |accessdate=01 April 2020}}</ref><ref name="MockAsymptom20">{{cite web |url=https://www.discovermagazine.com/health/asymptomatic-carriers-are-fueling-the-covid-19-pandemic-heres-why-you-dont |title=Asymptomatic Carriers Are Fueling the COVID-19 Pandemic. Here’s Why You Don’t Have to Feel Sick to Spread the Disease |author=Mock, J. |work=Discover |date=26 March 2020 |accessdate=01 April 2020}}</ref> This has become even more precarious with the highly contagious delta variant, which can be spread even by the vaccinated, highlighting that "measures such as masks and hand hygiene which can reduce transmission are important for everyone, regardless of vaccination status."<ref name="SubbaramanHowDo21">{{cite journal |title=How do vaccinated people spread Delta? What the science says |journal=Nature |author=Subbaraman, N. |volume=596 |pages=327–28 |year=2021 |doi=10.1038/d41586-021-02187-1 |pmid=34385613}}</ref>


Governmental reaction to the pandemic around the globe has varied significantly since the pandemic's declaration in March 2020. Some of that variance can be seen when reviewing the various policies implemented by the world's governments. The International Monetary Fund's policy tracker for COVID-19 response, for example, paints a picture of the laboratory testing, social, transportation, trade, and financial situations of each country. Reviewing the policy tracker reveals a diverse set of approaches from country to country, some significant and enduring, others limited and weak. <ref name="IMFPolicy20">{{cite web |url=https://www.imf.org/en/Topics/imf-and-covid19/Policy-Responses-to-COVID-19 |title=Policy Responses to COVID-19 |author=International Monetary Fund |publisher=International Monetary Fund |date=05 November 2020 |accessdate=12 November 2020}}</ref> Another source for examining government reaction is through the collation of data on how governments have implemented technological tracking measures in the name of slowing the epidemic. Groups like Privacy International collate such information through their collective tracking project, which links to hundreds of news stories concerning the use of mobile phone data, drones, and other surveillance mechanisms for tracking and enforcing quarantines; geolocation tracking though phones; and the implementation of facial recognition technology as part of a COVID-19 mitigation strategy.<ref name="PITracking20">{{cite web |url=https://privacyinternational.org/examples/tracking-global-response-covid-19 |title=Tracking the Global Response to COVID-19 |author=Privacy International |publisher=Privacy International |date=08 October 2020 |accessdate=12 November 2020}}</ref> Other projects such as the University of Oxford's COVID-19 Government Response Tracker also paint a broad picture of governments' responses to the pandemic using a wide variety of indicators, including school closures, travel restrictions, and vaccination policies. The University of Oxford maintains a core working paper and monthly regional reports, painting a picture of more governments decreasing policy changes as vaccination roll-out continues.<ref name="OxfordCOVID21">{{cite web |url=https://www.bsg.ox.ac.uk/research/research-projects/covid-19-government-response-tracker |title=COVID-19 Government Response Tracker |author=Blavatnik School of Government |publisher=University of Oxford |date=August 2021 |accessdate=06 September 2021}}</ref>
* ''Presymptomatic and asymptomatic virus shedding'': As mentioned in the previous point, carriers can be contagious during the presymptomatic phase of the disease, even while remaining symptom-free.<ref name="MandavilliInfected20" /><ref name="MockAsymptom20" /><ref name="YuenSARS20">{{cite journal |title=SARS-CoV-2 and COVID-19: The most important research questions |journal=Cell & Bioscience |author=Yuen, K.-S.; Fung, S.-Y.; Chan, C.-P.; Jin, D.-Y. |volume=10 |at=40 |year=2020 |doi=10.1186/s13578-020-00404-4 |pmid=32190290 |pmc=PMC7074995}}</ref><ref name="DiamondAsympt20">{{cite web |url=https://www.infectioncontroltoday.com/view/asymptomatic-carriers-covid-19-make-it-tough-target |title=Asymptomatic Carriers of COVID-19 Make It Tough to Target |author=Diamond, F. |work=Infection Control Today |date=17 March 2020 |accessdate=06 September 2021}}</ref> (The latest comprehensive research, from August 2021, appears to indicate that 35.1 percent of infected people may go without any recognizable symptoms after infection occurs.<ref name="SahAsymptom21>{{cite journal |title=Asymptomatic SARS-CoV-2 infection: A systematic review and meta-analysis |journal=PNAS |author=Sah, P.; Fitzpatrick, M.C.; Zimmer, C.F. et al. |volume=118 |issue=34 |at=e2109229118 |year=2021 |doi=10.1073/pnas.2109229118 |pmid=34376550}}</ref>) This contagion is a result of what's called [[viral shedding]], when the virus moves from cell to cell following successful reproduction. When the virus is in this state, it can be actively found in a carrier's body fluids, excrement, and other sources. Depending on the virus, the virus can then be introduced to another person via those sources. In the case of COVID-19, the core route of transmission appears to be through the air via aerosolized and other forms of water droplets, though saliva and other bodily constituents pose a transmission hazard due to shedding (see previous bulletpoint). Early in the pandemic, uncertainty about transmission routes of viral shedding, along with mixed messages early on about masks and their effectiveness for COVID-19<ref name="GreenfieldboyceWHO20">{{cite web |url=https://www.npr.org/2020/03/28/823292062/who-reviews-available-evidence-on-coronavirus-transmission-through-air |title=WHO Reviews 'Current' Evidence On Coronavirus Transmission Through Air |author=Greenfieldboyce, N. |work=NPR |date=28 March 2020 |accessdate=01 April 2020}}</ref><ref name="CSTEditorialIgnore31">{{cite web |url=https://chicago.suntimes.com/2020/3/31/21200144/coronavirus-covid-19-masks-wear-cdc-pritzker-trump-public-health-virus-face-cough-sneeze |title=Ignore the mixed messages and wear that mask |author=Chicago Sun Times Editorial Board |work=Chicago Sun Times |date=31 March 2020 |accessdate=01 April 2020}}</ref><ref name="MulhollandToMask20">{{cite web |url=http://www.rfi.fr/en/international/20200329-to-mask-or-not-to-mask-mixed-messages-in-a-time-of-coronavirus-crisis-france-covid-19-spread-droplets |title=To mask or not to mask: mixed messages in a time of crisis |author=Mulholland, J. |work=RFI |date=29 March 2020 |accessdate=01 April 2020}}</ref>,  caused problems. Today we know that masks and social distancing—when appropriate—are an even stronger necessity to limit community transmission of the disease from presymptomatic and asymptomatic individuals, even for those who are vaccinated.<ref name="SubbaramanHowDo21" />


Citizen reaction to the pandemic has also varied. Local governments in China have been criticized<ref name="WuChinese20">{{cite web |url=https://www.reuters.com/article/us-china-health-governor-idUSKBN1ZP0RU |title=Chinese provincial press conference on coronavirus inspires anger, criticism |author=Wu, H.; Cheng, L. |work=Reuters |date=26 January 2020 |accessdate=25 April 2020}}</ref><ref name="BJNewsJan21She">{{cite web |url=http://www.bjnews.com.cn/opinion/2020/01/21/677335.html |archiveurl=https://web.archive.org/web/20200128221902/http://www.bjnews.com.cn/opinion/2020/01/21/677335.html |title=武汉"万家宴":他们的淡定让人没法淡定 |author=She, Z. |work=The Beijing News |date=21 January 2020 |archivedate=28 January 2020 |accessdate=25 April 2020}}</ref>, while the central government has, at least at times, been seen in positive light for its handling of the pandemic.<ref name="JohnsonChina20">{{cite web |url=https://www.nytimes.com/2020/03/13/opinion/china-response-china.html |title=China Bought the West Time. The West Squandered It |author=Johnson, I. |work=The New York Times |date=13 March 2020 |accessdate=25 April 2020}}</ref><ref name="RichieDon't20">{{cite web |url=https://www.wacotrib.com/opinion/columns/guest_columns/rodney-richie-don-t-be-quick-to-blame-chinese-for-obscuring-viral-contagion/article_91f410f5-07a9-549a-9f8c-8b785bfc1207.html |title=Rodney Richie: Don’t be quick to blame Chinese for obscuring viral contagion |author=Richie, R. |work=Waco Tribune-Herald |date=28 March 2020 |accessdate=25 April 2020}}</ref><ref name="BowmanBill20">{{cite web |url=https://mynorthwest.com/1773883/bill-gates-coronavirus-reddit-ama/ |title=Bill Gates estimates at least 6-10 weeks before coronavirus is quelled in US |author=Bowman, N. |work=MYNorthwest |date=18 March 2020 |accessdate=25 April 2020}}</ref> Some Indians have criticized their government for its police brutality during lockdowns<ref name="PTICorona20">{{cite web |url=https://www.deccanherald.com/national/coronavirus-bollywood-celebrities-criticise-police-brutality-during-lockdown-818202.html |title=Coronavirus: Bollywood celebrities criticise police brutality during lockdown |author=PTI |work=Deccan Herald |date=27 March 2020 |accessdate=25 April 2020}}</ref>, while some Italians have criticized their government for trivializing the situation for too long.<ref name="HorowitzItaly20">{{cite web |url=https://www.nytimes.com/2020/03/21/world/europe/italy-coronavirus-center-lessons.html |title=Italy, Pandemic’s New Epicenter, Has Lessons for the World |author=Horowitz, J.; Bubola, E.; Povoledo, E. |work=The New York Times |date=21 March 2020 |accessdate=25 April 2020}}</ref> In the U.S.—and in other parts of the world—criticism has at times been significant concerning the United States government's response<ref name="SNSTheUnited20">{{cite web |url=https://www.science.org/news/2020/04/united-states-leads-coronavirus-cases-not-pandemic-response |title=The United States leads in coronavirus cases, but not pandemic response |author=Science News Staff |work=Science |date=01 April 2020 |accessdate=06 September 2021}}</ref><ref name="LuscombeTrump20">{{cite web |url=https://www.theguardian.com/world/2020/mar/22/trump-coronavirus-response-criticism-us-cases |title=Trump tries to blunt criticism of Covid-19 response as US cases pass 33,000 |author=Luscombe, R. |work=The Guardian |date=22 March 2020 |accessdate=25 April 2020}}</ref><ref name="PerryFact20">{{cite web |url=https://www.reuters.com/article/us-health-coronavirus-trump-who-reaction/factbox-global-reaction-to-trump-withdrawing-who-funding-idUSKCN21X0CN |title=Factbox: Global Reaction to Trump Withdrawing WHO Funding |author=Perry, M.; Kelland, K.; Nebehay, S. et al. |work=Reuters |date=14 April 2020 |accessdate=25 April 2020}}</ref><ref name="MeltonCritic20">{{cite web |url=https://providencemag.com/2020/04/criticizing-america-covid-19-response/ |title=Criticizing America over COVID-19 Response |author=Melton, M.; |work=Providence |date=03 April 2020 |accessdate=25 April 2020}}</ref>, though some governors have received praise for standing up for their state's citizens.<ref name="ClayBBC20">{{cite web |url=https://abc6onyourside.com/news/local/bbc-praises-gov-dewines-leadership-during-coronavirus-pandemic |title=BBC praises Gov. DeWine's leadership during coronavirus pandemic |author=Clay, J. |work=ABC6 On Your Side |date=31 March 2020 |accessdate=25 April 2020}}</ref><ref name="RenbaumGlendening20">{{cite web |url=https://marylandreporter.com/2020/03/20/glendening-praises-hogans-response-to-covid-19/ |title=Glendening Praises Hogan's Response to COVID-19 |author=Renbaum, B. |work=Maryland Reporter |date=20 March 2020 |accessdate=20 March 2020}}</ref><ref name="BarkanGlowing20">{{cite web |url=https://www.cjr.org/analysis/andrew-cuomo-coronavirus-covid19-barkan.php |title=Glowing coverage of Cuomo also raises difficult questions |work=Columbia Journalism Review |date=27 March 2020 |accessdate=25 April 2020}}</ref> American's views of presidential handling of the COVID-19 crisis have varied. During President Trump's tenure, Americans increasingly expressed disapproval with the U.S. president's handling of the COVID-19 crisis, from 47.8% dissapproval on April 8 to 57.1% disasapproval by the end of his term.<ref name="BycoffeHowAmer20">{{cite web |url=https://projects.fivethirtyeight.com/coronavirus-polls/ |title=How Americans View The Coronavirus Crisis And Trump's Response |author=Bycoffe, A.; Groskopf, C.; Mehta, D. |work=FiveThirtyEight |date=11 November 2020 |accessdate=12 November 2020}}</ref>, which seemingly aligned with his attempts to downplay the existence of the COVID-19 virus.<ref name="CollinsonFauci20">{{cite web |url=https://www.cnn.com/2020/06/23/politics/donald-trump-coronavirus-pandemic-election-2020/index.html |title=Fauci warns of disturbing trend as Trump ignores viral surge |author=Collinson, S. |work=CNN Politics |date=24 June 2020 |accessdate=07 July 2020}}</ref><ref name="HellmannTrump20">{{cite web |url=https://thehill.com/policy/healthcare/506075-trump-downplaying-sparks-new-criticism-of-covid-19-response |archiveurl=https://web.archive.org/web/20200707133105/https://thehill.com/policy/healthcare/506075-trump-downplaying-sparks-new-criticism-of-covid-19-response |title=Trump downplaying sparks new criticism of COVID-19 response |author=Hellmann, J. |work=The Hill |date=06 July 2020 |archivedate=07 July 2021 |accessdate=06 September 2021}}</ref> Americans' perceptions of President Biden's handling of COVID-19 began strong, at above 60% approval, but has weakened over time to 52.9% as of September 2021, largely falling along partisan lines.<ref name="BycoffeHowAmer20" />
* ''Understanding of high viral loads and infectious doses'': Respiratory diseases such as influenza, SARS, and MERS see a correlation between the infectious dose amount and the severity of disease symptoms, meaning the higher the infectious dose, the worse the symptoms.<ref name="GeddesDoesA20">{{cite web |url=https://www.newscientist.com/article/2238819-does-a-high-viral-load-or-infectious-dose-make-covid-19-worse/ |title=Does a high viral load or infectious dose make covid-19 worse? |author=Geddes, L. |work=New Scientist |date=27 March 2020 |accessdate=01 April 2020}}</ref> Similarly, viral load—a quantification of viral genomic fragments—also tends to correlate with clinical symptoms.<ref name="HijanoClinical19">{{cite journal |title=Clinical correlation of influenza and respiratory syncytial virus load measured by digital PCR |journal=PLoS One |author=Hijano, D.R.; Brazelton de Cardenas, J.; Maron, G. et al. |volume=14 |issue=9 |at=e0220908 |year=2019 |doi=10.1371/journal.pone.0220908 |pmid=31479459 |pmc=PMC6720028}}</ref> However, even with the breakthroughs in COVID research since the start of the pandemic, we are still in the investigative stages of definitively determining if that similarly holds true to COVID-19.<ref name="GeddesDoesA20" /><ref name="LiuViral20">{{cite journal |title=Viral dynamics in mild and severe cases of COVID-19 |journal=The Lancet Infectious Diseases |author=Liu, Y.; Yan, L.-M.; Wan, L. et al. |year=2020 |doi=10.1016/S1473-3099(20)30232-2 |pmid=32199493}}</ref><ref name="JoyntUnder20">{{cite journal |title=Understanding COVID-19: what does viral RNA load really mean? |journal=The Lancet Infectious Diseases |author=Joynt, G.M.; Wu, W.K.K. |year=2020 |doi=10.1016/S1473-3099(20)30237-1}}</ref> Research early on indicated, for example, there is little difference between the viral load of those with mild or no COVID-19 symptoms and those with more severe symptoms.<ref name="GeddesDoesA20" /> However, Pujadas ''et al.'' suggested a link between high viral load and overall mortality rate.<ref name="PujadasSARS20">{{cite journal |title=SARS-CoV-2 viral load predicts COVID-19 mortality |journal=The Lancet Respiratory Medicine |author=Pujadas, E.; Chaudhry, F.; McBride, R. et al. |year=2020 |doi=10.1016/S2213-2600(20)30354-4}}</ref> Research later in 2020 has suggested more of a positive correlation between severity of symptoms and viral load<ref name="FajnzylberSARS20">{{cite journal |title=SARS-CoV-2 viral load is associated with increased disease severity and mortality |journal=Nature Communications |author=Fajnzylber, J.; Regan, J.; Coxen, K. et al. |volume=11 |at=5493 |year=2020 |doi=10.1038/s41467-020-19057-5 |pmid=33127906 |pmc=PMC7603483}}</ref><ref name="AlAliSARS20">{{cite journal |title=SARS-Cov-2 Viral Load as an Indicator for COVID-19 Patients’ Hospital Stay |journal=medRxiv |year=2020 |doi=10.1101/2020.11.04.20226365}}</ref>, as has a July 2021 study published in ''Science''.<ref name="JonesEstim21">{{cite journal |title=Estimating infectiousness throughout SARS-CoV-2 infection course |journal=Science |author=Jones, T.C.; Biele, G.; Mühlemann, B. et al. |volume=373 |issue=6551 |at=abi5273 |year=2021 |doi=10.1126/science.abi5273 |pmid=34035154}}</ref> However, more research must be performed to better understand how the viral load infectious dose plays a role in transmission. Given the continued unknowns in this realm, wearing masks and getting vaccinate help minimize exposure and remain the best defense against the worst outcomes of the disease.<ref name="GeddesDoesA20" />


It's difficult to truly quantitatively (or qualitatively) measure the impact of COVID-19 on the world, let alone the United States. From the start of the pandemic there have been significant job losses<ref name="RothwellTheEffect20">{{cite web |url=https://www.brookings.edu/research/the-effect-of-covid-19-and-disease-suppression-policies-on-labor-markets-a-preliminary-analysis-of-the-data/ |title=The effect of COVID-19 and disease suppression policies on labor markets: A preliminary analysis of the data |author=Rothwell, J.; Van Drie, H. |work=Brookings |publisher=The Brookings Institute |date=27 April 2020 |accessdate=28 April 2020}}</ref> and bankruptcies<ref name="RosenbergAFlood20">{{cite web |url=https://apnews.com/article/virus-outbreak-business-courts-ap-top-news-small-business-b9ae754f44d27671ec63d85542c468f8 |title=A flood of business bankruptcies likely in coming months |author=Rosenberg, J.M. |work=Associated Press |date=26 April 2020 |accessdate=06 September 2021}}</ref>, to poor mental health impacts<ref name="TingCorona20">{{cite web |url=https://www.scmp.com/news/hong-kong/health-environment/article/3081582/coronavirus-suicide-experts-warn-pandemics-impact |title=Coronavirus: suicide experts warn of pandemic’s impact on mental health, with Hong Kong’s jobless, poor and elderly most at risk |author=Ting, V. |work=South China Morning Post |date=26 April 2020 |accessdate=28 April 2020}}</ref> and postponed cancer surgeries.<ref name="ColaianniForNow20">{{cite web |url=https://www.newyorker.com/science/medical-dispatch/for-now-we-wait-postponing-cancer-surgery-during-the-coronavirus-crisis |title=“For Now, We Wait”: Postponing Cancer Surgery During the Coronavirus Crisis |author=Colaianni, A. |work=The New Yorker |date=22 April 2020 |accessdate=28 April 2020}}</ref> With time, some firmer numbers have become known, however. As of August 31, 2021, the number of global confirmed cases of COVID-19 was more than 216 million, with more than 4.5 million people dead.<ref name=”WHOSitRep120_20”>{{cite web |url=https://www.who.int/docs/default-source/coronaviruse/situation-reports/20210831_weekly_epi_update_55.pdf |format=PDF |title=COVID-19 Weekly Epidemiological Update - 31 August 2021 |author=World Health Organization |publisher=World Health Organization |date=31 August 2021 |accessdate=06 November 2021}}</ref> As of July 2021, out of more than 320 vaccine candidates, 99 were still in clinical testing, 25 had reached Phase III efficacy studies, and 18 had received some form of formal approval.<ref name="TregoningProgress21">{{cite journal |title=Progress of the COVID-19 vaccine effort: viruses, vaccines and variants versus efficacy, effectiveness and escape |journal=Nature Reviews Immunology |author=Tregoning, J.S.; Flight, K.E.; Highman, S.L. et al. |pages=1–11 |year=2021 |doi=10.1038/s41577-021-00592-1 |pmid=34373623 |pmc=PMC8351583}}</ref> Some 3.2 billion doses of vaccine had been administered globally as of July 2021 (with the caveat that only ~1% of people in low-income countries have received at least one dose), and nearly 11 billion doses were still needed to fully vaccinate 70% of the world's population.<ref name="PadmaCOVID21">{{cite journal |title=COVID vaccines to reach poorest countries in 2023 — despite recent pledges |journal=Nature |author=Padma, T.V. |volume=595 |pages=342–43 |year=2021 |doi=10.1038/d41586-021-01762-w |pmid=34226742}}</ref> Other statistics include:
* ''Cardiovascular issues'': Coronaviruses and their accompanying respiratory infections are known to complicate issues of the cardiovascular system, which in turn may "increase the incidence and severity" of infectious diseases such as SARS and COVID-19.<ref name="MadjidPotent20">{{cite journal |title=Potential Effects of Coronaviruses on the Cardiovascular System |journal=JAMA Cardiology |author=Madjid, M.; Safavi-Naeini, P.; Solomon, S.D. |year=2020 |doi=10.1001/jamacardio.2020.1286 |pmid=32219363}}</ref><ref name="XiongCorona20">{{cite journal |title=Coronaviruses and the cardiovascular system: acute and long-term implications |journal=European Heart Journal |author=Xiong, T.-Y.; Redwood, S.; Prendergast, B.; Chen, M. |at=ehaa231 |year=2020 |doi=10.1093/eurheartj/ehaa231 |pmid=32186331}}</ref><ref name="DrigginCardio20">{{cite journal |title=Cardiovascular Considerations for Patients, Health Care Workers, and Health Systems During the Coronavirus Disease 2019 (COVID-19) Pandemic |journal=Journal of the American College of Cardiology |author=Driggin, E.; Madhavan, M.V.; Bikdeli, B. et al. |year=2020 |doi=10.1016/j.jacc.2020.03.031 |pmid=32201335}}</ref> While the exact cardiac effect COVID-19 has on patients is still unknown, suspicion is those with "hypertension, diabetes, and diagnosed cardiovascular disease" may be more prone to having cardiovascular complications from the disease.<ref name="OttoCardiac20">{{cite web |url=https://www.the-hospitalist.org/hospitalist/article/219645/coronavirus-updates/cardiac-symptoms-can-be-first-sign-covid-19 |title=Cardiac symptoms can be first sign of COVID-19 |author=Otto, M.A. |work=The Hospitalist |date=26 March 2020 |accessdate=01 April 2020}}</ref><ref name="ClerkinCorona20">{{cite journal |title=Coronavirus Disease 2019 (COVID-19) and Cardiovascular Disease |journal=Circulation |author=Clerkin, K.J.; Fried, J.A.; Raikhelkar, J. et al. |year=2020 |doi=10.1161/CIRCULATIONAHA.120.046941 |pmid=32200663}}</ref> Current thinking is SARS-CoV-2 either attacks heart tissues, causing myocardial dysfunction, or inevitably causes heart failure through a "cytokine storm,"<ref name="MadjidPotent20" /><ref name="XiongCorona20" /><ref name="OttoCardiac20" /><ref name="ClerkinCorona20" /><ref name="MehtaCOVID20">{{cite journal |title=COVID-19: Consider cytokine storm syndromes and immunosuppression |journal=The Lancet |author=Mehta, P.; McAuley, D.F.; Brown, M. et al. |volume=395 |issue=10229 |pages=P1033–34 |year=2020 |doi=10.1016/S0140-6736(20)30628-0 |pmid=32192578}}</ref><ref name="MandavilliTheCoronaCyto20">{{cite web |url=https://www.nytimes.com/2020/04/01/health/coronavirus-cytokine-storm-immune-system.html |title=The Coronavirus Patients Betrayed by Their Own Immune Systems |author=Mandavilli, A. |work=The New York Times |date=01 April 2020 |accessdate=01 April 2020}}</ref><ref name="WeidmannLab20">{{cite journal |title=Laboratory Biomarkers in the Management of Patients With COVID-19 |journal=American Journal of Clinical Pathology |author=Weidmann, M.D.; Otori, J.; Rai, A.J. |at=aqaa205 |year=2020 |doi=10.1093/ajcp/aqaa205 |pmid=33107558}}</ref>, an overproduction of signaling molecules that promote inflammation by white blood cells (leukocytes).<ref name="TisoncikInto12">{{cite journal |title=Into the eye of the cytokine storm |journal=Microbiology and Molecular Biology Reviews |author=Tisoncik, J.R.; Korth, M.J.; Simmons, C.P. et al. |volume=76 |issue=1 |pages=16–32 |year=2012 |doi=10.1128/MMBR.05015-11 |pmid=22390970 |pmc=PMC3294426}}</ref><ref name="YangTheSig21">{{cite journal |title=The signal pathways and treatment of cytokine storm in COVID-19 |journal=Signal Transduction and Targeted Therapy |author=Yang, L.; Xie, X.; Tu, Z. et al. |volume=6 |at=255 |year=2021 |doi=10.1038/s41392-021-00679-0 |pmid=34234112 |pmc=PMC8261820}}</ref> What's scary is that like the 1918 Spanish flu, SARS, and other epidemics, some otherwise healthy patients' immune responses are entirely overreactive, leading to acute respiratory distress syndrome (ARDS) or heart failure.<ref name="WeidmannLab20" /><ref name="MandavilliTheCoronaCyto20" /><ref name="BasilioANew20">{{cite web |url=https://www.mdlinx.com/article/a-new-potential-risk-of-covid-19-sudden-cardiac-death/3z05mHtQN0PL1EdhlWltmH |title=A new potential risk of COVID-19: Sudden cardiac death |author=Basilio, P. |work=MDLinx |date=26 March 2020 |accessdate=06 September 2021}}</ref> Additionally, as the disease has progressed, medical professionals have noted two additional cardiovascular issues. First, an atypical amount of blood clotting has shown up in some infected patients, which may be related to overreactive immune systems, autoantibodies, and underlying health conditions.<ref name="RettnerMyster20">{{cite web |url=https://www.livescience.com/coronavirus-blood-clots.html |title=Mysterious blood clots in COVID-19 patients have doctors alarmed |author=Rettner, R. |work=LiveScience |date=23 April 2020 |accessdate=28 April 2020}}</ref><ref name="HamptonAuto21">{{cite journal |title=Autoantibodies May Drive COVID-19 Blood Clots |journal=JAMA |author=Hampton, T. |volume=325 |issue=5 |page=425 |year=2021 |doi=10.1001/jama.2020.25699 |pmid=33528515}}</ref> Second, what is being called pediatric multisystem inflammatory syndrome (PMIS) or multisystem inflammatory syndrome in children (MIS-C) has shown up in children after the infection has passed, characterized by inflamed blood vessels and toxic shock syndrome.<ref name="MoyerWhatWe20">{{cite web |url=https://www.nytimes.com/2020/05/19/parenting/pmis-coronavirus-children.html |title=What We Know About the Covid-Related Syndrome Affecting Children |work=The New York Times |author=Moyer, M.W. |date=19 May 2020 |accessdate=19 May 2020}}</ref><ref name="FischerWhatTo20">{{cite web |url=https://www.healthline.com/health-news/what-to-know-pmis-syndrome-linked-to-covid-19-affects-children |title=What to Know About PMIS, the COVID-19-Linked Syndrome Affecting Children |work=Healthline |author=Fischer, K. |date=18 May 2020 |accessdate=19 May 2020}}</ref><ref name="MacMillanResearch21">{{cite web |url=https://www.yalemedicine.org/news/multisystem-inflammatory-syndrome-in-children-misc-covid-kids |title=Researchers Continue to Find Clues About MIS-C |author=MacMillan, C. |work=Yale Medicine |publisher=Yale University |date=14 July 2021 |accessdate=06 September 2021}}</ref> While research is ongoing to determine whether these seemingly hyperactive cardiovascular responses are directly linked to the virus<ref name="MannePlatelet20">{{cite journal |title=Platelet Gene Expression and Function in COVID-19 Patients |journal=Blood |author=Manne, B.K.; Denorme, F.; Middleton, E.A. et al. |at=blood.2020007214 |year=2020 |doi=10.1182/blood.2020007214}}</ref> or if virus-independent immunopathology is responsible<ref name="DorwardTissue20">{{cite journal |title=Tissue-specific tolerance in fatal Covid-19 |journal=medRxiv |author=Dorward, D.A.; Russell, C.D.; Um, I.H. et al. |year=2020 |doi=10.1101/2020.07.02.20145003}}</ref>, these uncertainties only emphasize the level of difficulty of properly treating COVID-19.


* "The global economy contracted by 3.5 percent in 2020 according to the April 2021 World Economic Outlook Report published by the IMF, a 7 percent loss relative to the 3.4 percent growth forecast back in October 2019."<ref name="YeyatiSocial21">{{cite web |url=https://www.brookings.edu/research/social-and-economic-impact-of-covid-19/ |title=Social and economic impact of COVID-19 |author=Yeyati, E.L.; Filippini, F. |work=Brookings |date=08 June 2021 |accessdate=06 September 2021}}</ref>
* ''Other systemic and bodily issues'': As the pandemic has progressed, researchers have discovered SARS-CoV-2 appears to negatively impact other organs and systems in the human body, including the renal system, digestive system, endocrine system, neurological system, and even the reproductive system.<ref name="WeidmannLab20" /><ref name="CDCSymptoms20">{{cite web |url=https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/symptoms.html |title=Symptoms of Coronavirus |author=Centers for Disease Control and Preventions |publisher=Centers for Disease Control and Preventions |date=22 February 2021 |accessdate=06 September 2021}}</ref><ref name="MayoCOVID20">{{cite web |url=https://www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/coronavirus-long-term-effects/art-20490351 |title=COVID-19 (coronavirus): Long-term effects |author=Mayo Clinic Staff |publisher=Mayo Clinic |date=07 October 2020 |accessdate=12 November 2020}}</ref><ref name="BudsonTheHidden20">{{cite web |url=https://www.health.harvard.edu/blog/the-hidden-long-term-cognitive-effects-of-covid-2020100821133 |title=The hidden long-term cognitive effects of COVID-19 |author=Budson, A.E. |work=Harvard Health Blog |date=08 October 2020 |accessdate=12 November 2020}}</ref><ref name="MaCOVID20">{{cite journal |title=COVID-19 and the Digestive System |journal=American Journal of Gastroenterology |author=Ma, C.; Cong, Y.; Zhang, H. |volume=115 |issue=7 |pages=1003–6 |year=2020 |doi=10.14309/ajg.0000000000000691 |pmid=32618648 |pmc=PMC7273952}}</ref> Another bodily issue that appears to remain for a subset of post-recovery COVID-19 patients is fatigue. The University of Minnesota's Center for Infectious Disease Research and Policy reports on an observational study published in ''PLOS One''' that showed more than half of people who recovered from their COVID-19 infection still dealt with the lingering effects of fatigue at a median of 10 weeks after recovery. The study reports no link between the persistent fatigue and severity of symptoms, need for hospitalization, concentration of laboratory biomarkers, and age.<ref name="VanBeusekomHalf20">{{cite web |url=https://www.cidrap.umn.edu/news-perspective/2020/11/half-recovered-covid-19-patients-report-lingering-fatigue |title=Half of recovered COVID-19 patients report lingering fatigue |author=Van Beusekom, M. |work=CUDRAP News & Perspective |publisher=University of Minnesota |date=11 November 2020 |accessdate=18 November 2020}}</ref> These systemic and body issues have added further complication to an already complicated disease, making extended treatment planning difficult. The long-term affects of these and other organ system injuries remains to be fully understood.
* "At a global scale, the fiscal support [applied to COVID-19] reached nearly $16 trillion (around 15 percent of global GDP) in 2020."<ref name="YeyatiSocial21" />
* As of July 2021, some 10 percent of American adults have reported sometimes or often not having enough to eat in a given week, compared to 3.4 percent for the entirety of 2019.<ref name="CBPPTracking21">{{cite web |url=https://www.cbpp.org/research/poverty-and-inequality/tracking-the-covid-19-recessions-effects-on-food-housing-and |title=Tracking the COVID-19 Recession’s Effects on Food, Housing, and Employment Hardships |work=COVID Hardship Watch |author=Center on Budget and Policy Priorities |date=09 August 2021 |accessdate=06 September 2021}}</ref>
* "An estimated 11.4 million [U.S.] adults living in rental housing—16 percent of adult renters—were not caught up on rent" as of the beginning of July 2021, with an additional 7.4 million estimated to not be caught up on mortgage payments.<ref name="CBPPTracking21" />
* "Some 63 million [U.S.] adults—27 percent of all adults in the country—reported it was somewhat or very difficult for their household to cover usual expenses in the past seven days," as of the beginning of July 2021.<ref name="CBPPTracking21" />


Despite the remaining unknowns and difficulties facing societies everywhere, what has long been known and remains true, however, is that preventative measures such as wearing masks<ref name="FalconDoFace21">{{cite web |url=https://www.kxan.com/news/coronavirus/do-face-masks-work-here-are-49-scientific-studies-that-explain-why-they-do/ |title=Do face masks work? Here are 49 scientific studies that explain why they do |author=Falcon, R. |work=KXAN |date=07 August 2021 |accessdate=06 September 2021}}</ref>, getting vaccinated<ref name="TregoningProgress21" />, and getting tested for exposure<ref name="ScottWhyCant21">{{cite web |url=https://www.vox.com/coronavirus-covid19/2021/9/1/22642745/us-covid-19-test-numbers-delta-variant |title=Why can’t America fix its Covid-19 testing problems? |author=Scott, D. |work=Vox |date=01 September 2021 |accessdate=06 September 2021}}</ref> remain vital in order to further limit the negative consequences of the pandemic.
* ''Mental health concerns'': The mental health toll of the pandemic is becoming increasingly apparent as it wears on. A June 2020 CDC survey of 5,412 U.S. adults (regardless of infection status) "found that 40.9% of respondents reported 'at least one adverse mental or behavioral health condition,' including depression, anxiety, posttraumatic stress, and substance abuse, with rates that were three to four times the rates one year earlier." More than 10 percent of respondents also indicated they had seriously considered suicide in a time period thirty days prior to responding.<ref name="SimonMental20">{{cite journal |title=Mental Health Disorders Related to COVID-19–Related Deaths |journal=JAMA |author=Simon, N.M.; Saxe, G.N.; Marmar, C.R. |volume=324 |issue=15 |pages=1493–94 |year=2020 |doi=10.1001/jama.2020.19632 |pmid=33044510}}</ref> From an inability to grieve communally with loved ones, to income loss, increased anxiety, and long periods of social isolation, these increasing numbers are not surprising, particularly in light of research on previous pandemics.<ref name="SimonMental20" /><ref name="SavageCorona20">{{cite web |url=https://www.bbc.com/worklife/article/20201021-coronavirus-the-possible-long-term-mental-health-impacts |title=Coronavirus: The possible long-term mental health impacts |author=Savage, M. |work=BBC Worklife |date=28 October 2020 |accessdate=18 November 2020}}</ref> Without proper treatment, these conditions may worsen into prolonged grief disorder, only exasperating a growing mental health crisis.<ref name="SimonMental20" /> Further, at least one study suggests that those who contract COVID-19 may be at a greater risk of developing some sort of mental illness within 90 days, including anxiety, depression, and insomnia. This effect may be worse for those who already have a history of mental health illness.<ref name="KellandStudy20">{{cite web |url=https://www.insurancejournal.com/news/international/2020/11/09/590113.htm |title=Study Shows COVID-19 Patients at Greater Risk of Mental Health Problems |author=Kelland, K. |work=Insurance Journal |date=09 November 2020 |accessdate=18 November 2020}}</ref> Mitigating the effects of these mental health concerns will require further study, greater funding, expanded screening, and improved focus on community methods of dealing with tragedy and loss.<ref name="SimonMental20" />


==References==
==References==
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{{Reflist|colwidth=30em}}

Revision as of 16:38, 3 February 2022

The graphical abstract from Li et al. 2020, showing general features of SARS-CoV-2, current knowledge of molecular immune pathogenesis, and diagnosis methods of COVID-19 based on present understanding of SARS-CoV and MERS-CoV viral infections

COVID-19 has presented numerous societal challenges, from supply line interruptions and economic sagging to overwhelmed healthcare systems and civil disorder. However, these are largely the social, economic, and political ripple effects of a disease that has brought with it a set of inherent attributes that make it more difficult to manage in human populations than say the flu.

However, COVID-19 is not the flu, and it is indeed worse in its effects than the flu, contrary to many people's perceptions. Yes, COVID-19 and the flu have some symptom overlap. Yes, COVID-19 and the flu have some transmission type overlap. But from there it diverges. COVID-19 and SARS-CoV-2 is different in that it is more prone to be transmitted to others during the presymptomatic phase. And the body of evidence has grown since early on in the pandemic[1] that SARS-CoV-2 is transmittable predominately via an airborne route[2][3][4][5], though transmission from contaminated surfaced or physical intimacy are also believed possible.[6][7] Hospitalization rates are higher, perhaps up to 10 times higher than the flu, and hospital stays are longer with COVID-19. People are dying more often from COVID-19 too, up to 10 times more often than people stricken with the flu.[8][9][10] And while flu vaccines are largely the norm around the world, and COVID-19 vaccines are gradually becoming more available, those who willing choose to not get the vaccine have a massively higher chance of dying from COVID-19 (as of August 2021, more than 99 percent of all deaths from COVID-19 are found with the unvaccinated[11], compared to some 80% of children who die from the flu while unvaccinated[12]).

Other aspects of the disease that make it difficult to manage include:

  • Median incubation period: According to research published in Annals of Internal Medicine, the median (i.e., the central tendency, which is less skewed than average[13]) incubation period is 5.1 days (Note that as new variants arrive, incubation times my change; the delta variant is thought to have an incubation period of four days, for example.[14]), with 97.5% of symptomatic carriers showing symptoms within 11.5 days. The authors found this to be compatible with U.S. government recommendations of monitored 14-day self-quarantines if individuals were at risk of exposure.[15] However, many people continue to not take mask-wearing—and vaccination—seriously, and thus unmasked presymptomatic (and asymptomatic) carriers are thus largely more prone to spreading the virus.[16][17] This has become even more precarious with the highly contagious delta variant, which can be spread even by the vaccinated, highlighting that "measures such as masks and hand hygiene which can reduce transmission are important for everyone, regardless of vaccination status."[18]
  • Presymptomatic and asymptomatic virus shedding: As mentioned in the previous point, carriers can be contagious during the presymptomatic phase of the disease, even while remaining symptom-free.[16][17][19][20] (The latest comprehensive research, from August 2021, appears to indicate that 35.1 percent of infected people may go without any recognizable symptoms after infection occurs.[21]) This contagion is a result of what's called viral shedding, when the virus moves from cell to cell following successful reproduction. When the virus is in this state, it can be actively found in a carrier's body fluids, excrement, and other sources. Depending on the virus, the virus can then be introduced to another person via those sources. In the case of COVID-19, the core route of transmission appears to be through the air via aerosolized and other forms of water droplets, though saliva and other bodily constituents pose a transmission hazard due to shedding (see previous bulletpoint). Early in the pandemic, uncertainty about transmission routes of viral shedding, along with mixed messages early on about masks and their effectiveness for COVID-19[22][23][24], caused problems. Today we know that masks and social distancing—when appropriate—are an even stronger necessity to limit community transmission of the disease from presymptomatic and asymptomatic individuals, even for those who are vaccinated.[18]
  • Understanding of high viral loads and infectious doses: Respiratory diseases such as influenza, SARS, and MERS see a correlation between the infectious dose amount and the severity of disease symptoms, meaning the higher the infectious dose, the worse the symptoms.[25] Similarly, viral load—a quantification of viral genomic fragments—also tends to correlate with clinical symptoms.[26] However, even with the breakthroughs in COVID research since the start of the pandemic, we are still in the investigative stages of definitively determining if that similarly holds true to COVID-19.[25][27][28] Research early on indicated, for example, there is little difference between the viral load of those with mild or no COVID-19 symptoms and those with more severe symptoms.[25] However, Pujadas et al. suggested a link between high viral load and overall mortality rate.[29] Research later in 2020 has suggested more of a positive correlation between severity of symptoms and viral load[30][31], as has a July 2021 study published in Science.[32] However, more research must be performed to better understand how the viral load infectious dose plays a role in transmission. Given the continued unknowns in this realm, wearing masks and getting vaccinate help minimize exposure and remain the best defense against the worst outcomes of the disease.[25]
  • Cardiovascular issues: Coronaviruses and their accompanying respiratory infections are known to complicate issues of the cardiovascular system, which in turn may "increase the incidence and severity" of infectious diseases such as SARS and COVID-19.[33][34][35] While the exact cardiac effect COVID-19 has on patients is still unknown, suspicion is those with "hypertension, diabetes, and diagnosed cardiovascular disease" may be more prone to having cardiovascular complications from the disease.[36][37] Current thinking is SARS-CoV-2 either attacks heart tissues, causing myocardial dysfunction, or inevitably causes heart failure through a "cytokine storm,"[33][34][36][37][38][39][40], an overproduction of signaling molecules that promote inflammation by white blood cells (leukocytes).[41][42] What's scary is that like the 1918 Spanish flu, SARS, and other epidemics, some otherwise healthy patients' immune responses are entirely overreactive, leading to acute respiratory distress syndrome (ARDS) or heart failure.[40][39][43] Additionally, as the disease has progressed, medical professionals have noted two additional cardiovascular issues. First, an atypical amount of blood clotting has shown up in some infected patients, which may be related to overreactive immune systems, autoantibodies, and underlying health conditions.[44][45] Second, what is being called pediatric multisystem inflammatory syndrome (PMIS) or multisystem inflammatory syndrome in children (MIS-C) has shown up in children after the infection has passed, characterized by inflamed blood vessels and toxic shock syndrome.[46][47][48] While research is ongoing to determine whether these seemingly hyperactive cardiovascular responses are directly linked to the virus[49] or if virus-independent immunopathology is responsible[50], these uncertainties only emphasize the level of difficulty of properly treating COVID-19.
  • Other systemic and bodily issues: As the pandemic has progressed, researchers have discovered SARS-CoV-2 appears to negatively impact other organs and systems in the human body, including the renal system, digestive system, endocrine system, neurological system, and even the reproductive system.[40][51][52][53][54] Another bodily issue that appears to remain for a subset of post-recovery COVID-19 patients is fatigue. The University of Minnesota's Center for Infectious Disease Research and Policy reports on an observational study published in PLOS One' that showed more than half of people who recovered from their COVID-19 infection still dealt with the lingering effects of fatigue at a median of 10 weeks after recovery. The study reports no link between the persistent fatigue and severity of symptoms, need for hospitalization, concentration of laboratory biomarkers, and age.[55] These systemic and body issues have added further complication to an already complicated disease, making extended treatment planning difficult. The long-term affects of these and other organ system injuries remains to be fully understood.
  • Mental health concerns: The mental health toll of the pandemic is becoming increasingly apparent as it wears on. A June 2020 CDC survey of 5,412 U.S. adults (regardless of infection status) "found that 40.9% of respondents reported 'at least one adverse mental or behavioral health condition,' including depression, anxiety, posttraumatic stress, and substance abuse, with rates that were three to four times the rates one year earlier." More than 10 percent of respondents also indicated they had seriously considered suicide in a time period thirty days prior to responding.[56] From an inability to grieve communally with loved ones, to income loss, increased anxiety, and long periods of social isolation, these increasing numbers are not surprising, particularly in light of research on previous pandemics.[56][57] Without proper treatment, these conditions may worsen into prolonged grief disorder, only exasperating a growing mental health crisis.[56] Further, at least one study suggests that those who contract COVID-19 may be at a greater risk of developing some sort of mental illness within 90 days, including anxiety, depression, and insomnia. This effect may be worse for those who already have a history of mental health illness.[58] Mitigating the effects of these mental health concerns will require further study, greater funding, expanded screening, and improved focus on community methods of dealing with tragedy and loss.[56]

References

  1. Achenach, J.; Johnson, C.Y. (29 April 2020). "Studies leave question of ‘airborne’ coronavirus transmission unanswered". The Washington Post. https://www.washingtonpost.com/health/2020/04/29/studies-leave-question-airborne-coronavirus-transmission-unanswered/. Retrieved 01 May 2020. 
  2. Van Beusekom, M. (6 July 2020). "Global experts: Ignoring airborne COVID spread risky". Center for Infectious Disease Research and Policy. University of Minnesota. https://www.cidrap.umn.edu/news-perspective/2020/07/global-experts-ignoring-airborne-covid-spread-risky. Retrieved 07 July 2020. 
  3. Ducharme, J. (7 July 2020). "The WHO Says Airborne Coronavirus Transmission Isn't a Big Risk. Scientists Are Pushing Back". Time. https://time.com/5863220/airborne-coronavirus-transmission/. Retrieved 07 July 2020. 
  4. Penn Medicine (2 August 2020). "COVID-19 Transmission: Droplet or Airborne? Penn Medicine Epidemiologists Issue Statement". Penn Physician Blog. https://www.pennmedicine.org/updates/blogs/penn-physician-blog/2020/august/airborne-droplet-debate-article. Retrieved 23 August 2020. 
  5. Greenhalgh, T.; Jimenez, J.L.; Prather, K.A. et al. (2021). "Ten scientific reasons in support of airborne transmission of SARS-CoV-2". Lancet 397 (10285): 1603–5. doi:10.1016/S0140-6736(21)00869-2. PMC PMC8049599. PMID 33865497. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8049599. 
  6. "Science Brief: SARS-CoV-2 and Surface (Fomite) Transmission for Indoor Community Environments". Centers for Disease Control and Prevention. 5 April 2021. https://www.cdc.gov/coronavirus/2019-ncov/more/science-and-research/surface-transmission.html. Retrieved 06 September 2021. 
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