The pandemic's true death toll". The Economist. 28 August 2023 [2 November 2021] . Retrieved 28 August 2023. The standard methods of testing for presence of SARS-CoV-2 are nucleic acid tests, [20] [164] which detects the presence of viral RNA fragments. [165] As these tests detect RNA but not infectious virus, its "ability to determine duration of infectivity of patients is limited." [166] The test is typically done on respiratory samples obtained by a nasopharyngeal swab; however, a nasal swab or sputum sample may also be used. [167] [168] Results are generally available within hours. [20] The WHO has published several testing protocols for the disease. [169]

Covid inquiry: The UK pandemic in numbers - BBC News

Gover AR, Harper SB, Langton L (July 2020). "Anti-Asian Hate Crime During the COVID-19 Pandemic: Exploring the Reproduction of Inequality". American Journal of Criminal Justice. 45 (4): 647–667. doi: 10.1007/s12103-020-09545-1. PMC 7364747. PMID 32837171. Grant MC, Geoghegan L, Arbyn M, Mohammed Z, McGuinness L, Clarke EL, Wade RG (23 June 2020). "The prevalence of symptoms in 24,410 adults infected by the novel coronavirus (SARS-CoV-2; COVID-19): A systematic review and meta-analysis of 148 studies from 9 countries". PLOS ONE. 15 (6): e0234765. Bibcode: 2020PLoSO..1534765G. doi: 10.1371/journal.pone.0234765. PMC 7310678. PMID 32574165. S2CID 220046286. The COVID‑19 vaccines are widely credited for their role in reducing the spread of COVID‑19 and reducing the severity and death caused by COVID‑19. [199] [202] According to a June 2022 study, COVID‑19 vaccines prevented an additional 14.4 to 19.8 million deaths in 185 countries and territories from 8 December 2020 to 8 December 2021. [203] [204] Many countries implemented phased distribution plans that prioritized those at highest risk of complications, such as the elderly, and those at high risk of exposure and transmission, such as healthcare workers. [205] [206]

For deaths statistics, the ONS, along with its counterparts in Scotland and Northern Ireland, counts all deaths where Covid is on the death certificate. About 90% of these deaths are directly due to Covid, while it is a contributory factor in the remaining deaths. These figures differ from the daily figures the government used to publish every day throughout the pandemic. These figures included any deaths that have occurred within 28 days of a positive test. As of 1October2021 [update], Reuters reported that it had estimated the worldwide total number of deaths due to COVID‑19 to have exceeded five million. [451] Half of young adults with COVID-19 had persistent symptoms after 6 months". medicalxpress.com . Retrieved 10 July 2021. Starting June 18, data for Scotland will include testing results from the U.K. Government’s Regional Testing Centres, in addition to data from NHS Laboratories. Scotland did not update data from June 15 to June 17 while preparing this change.

COVID-19 - Wikipedia

Bourouiba L (13 July 2021). "Fluid Dynamics of Respiratory Infectious Diseases". Annual Review of Biomedical Engineering. 23 (1): 547–577. doi: 10.1146/annurev-bioeng-111820-025044. hdl: 1721.1/131115. PMID 34255991. S2CID 235823756 . Retrieved 7 September 2021. a b c d e Li C, Zhao C, Bao J, Tang B, Wang Y, Gu B (November 2020). "Laboratory diagnosis of coronavirus disease-2019 (COVID-19)". Clinica Chimica Acta; International Journal of Clinical Chemistry. 510: 35–46. doi: 10.1016/j.cca.2020.06.045. PMC 7329657. PMID 32621814. Several measures are commonly used to quantify mortality. [329] These numbers vary by region and over time and are influenced by the volume of testing, healthcare system quality, treatment options, time since the initial outbreak, and population characteristics such as age, sex, and overall health. [330]Long B, Brady WJ, Koyfman A, Gottlieb M (July 2020). "Cardiovascular complications in COVID-19". The American Journal of Emergency Medicine. 38 (7): 1504–1507. doi: 10.1016/j.ajem.2020.04.048. PMC 7165109. PMID 32317203. Blood and vessels: disseminated intravascular coagulation (DIC); [182] leukoerythroblastic reaction, [183] endotheliitis, [184] hemophagocytosis [184] Another common cause of death is complications related to the kidneys. [139] Early reports show that up to 30% of hospitalised patients both in China and in New York have experienced some injury to their kidneys, including some persons with no previous kidney problems. [144] Immunopathology Key components of the adaptive immune response to SARS-CoV-2 a b Morawska L, Allen J, Bahnfleth W, Bluyssen PM, Boerstra A, Buonanno G, etal. (May 2021). "A paradigm shift to combat indoor respiratory infection" (PDF). Science. 372 (6543): 689–691. Bibcode: 2021Sci...372..689M. doi: 10.1126/science.abg2025. PMID 33986171. S2CID 234487289. Archived from the original (PDF) on 6 December 2021 . Retrieved 14 June 2021.

BBC News Covid inquiry: The UK pandemic in numbers - BBC News

Although SARS-CoV-2 has a tropism for ACE2-expressing epithelial cells of the respiratory tract, people with severe COVID‑19 have symptoms of systemic hyperinflammation. Clinical laboratory findings of elevated IL‑2, IL‑7, IL‑6, granulocyte-macrophage colony-stimulating factor (GM‑CSF), interferon gamma-induced protein 10 (IP‑10), monocyte chemoattractant protein 1 (MCP1), macrophage inflammatory protein 1‑alpha (MIP‑1‑alpha), and tumour necrosis factor (TNF‑α) indicative of cytokine release syndrome (CRS) suggest an underlying immunopathology. [135] CDC (11 February 2020). "COVID-19 and Your Health". Centers for Disease Control and Prevention . Retrieved 23 January 2021.Around 10% to 30% of non-hospitalised people with COVID-19 go on to develop long COVID. For those that do need hospitalisation, the incidence of long-term effects is over 50%. [14] Long COVID is an often severe multisystem disease, with a large set of symptoms. There are likely various, possibly coinciding, causes. [14] Organ damage from the acute infection can explain a part of the symptoms, but long COVID is also observed in people where organ damage seems to be absent. [317]

Coronavirus | The Guardian Coronavirus | The Guardian

McNeil Jr DG (2 February 2020). "Wuhan Coronavirus Looks Increasingly Like a Pandemic, Experts Say". The New York Times. ISSN 0362-4331. Archived from the original on 2 February 2020 . Retrieved 4 April 2020. As is common with infections, there is a delay between the moment a person first becomes infected and the appearance of the first symptoms. The median delay for COVID-19 is four to five days [50] possibly being infectious on 1-4 of those days. [51] Most symptomatic people experience symptoms within two to seven days after exposure, and almost all will experience at least one symptom within 12 days. [50] [52] Novel Coronavirus (2019-nCoV) Situation Report – 1" (PDF). World Health Organization (WHO). 21 January 2020. a b c Sanders JM, Monogue ML, Jodlowski TZ, Cutrell JB (May 2020). "Pharmacologic Treatments for Coronavirus Disease 2019 (COVID-19): A Review". JAMA. 323 (18): 1824–1836. doi: 10.1001/jama.2020.6019. PMID 32282022. Tocilizumab has been included in treatment guidelines by China's National Health Commission after a small study was completed. [506] [507] It is undergoing a Phase II non-randomised trial at the national level in Italy after showing positive results in people with severe disease. [508] [509] Combined with a serum ferritin blood test to identify a cytokine storm (also called cytokine storm syndrome, not to be confused with cytokine release syndrome), it is meant to counter such developments, which are thought to be the cause of death in some affected people. [510] The interleukin-6 receptor (IL-6R) antagonist was approved by the FDA to undergo a Phase III clinical trial assessing its effectiveness on COVID‑19 based on retrospective case studies for the treatment of steroid-refractory cytokine release syndrome induced by a different cause, CAR T cell therapy, in 2017. [511] There is no randomised, controlled evidence that tocilizumab is an efficacious treatment for CRS. Prophylactic tocilizumab has been shown to increase serum IL-6 levels by saturating the IL-6R, driving IL-6 across the blood–brain barrier, and exacerbating neurotoxicity while having no effect on the incidence of CRS. [512]CDC (11 February 2020). "Post-COVID Conditions". U.S. Centers for Disease Control and Prevention (CDC) . Retrieved 12 July 2021. On many surfaces, including glass, some types of plastic, stainless steel, and skin, the virus can remain infective for several days indoors at room temperature, or even about a week under ideal conditions. [248] [249] On some surfaces, including cotton fabric and copper, the virus usually dies after a few hours. [248] The virus dies faster on porous surfaces than on non-porous surfaces due to capillary action within pores and faster aerosol droplet evaporation. [250] [243] [248] However, of the many surfaces tested, two with the longest survival times are N95 respirator masks and surgical masks, both of which are considered porous surfaces. [248] Oran DP, Topol EJ (May 2021). "The Proportion of SARS-CoV-2 Infections That Are Asymptomatic: A Systematic Review". Annals of Internal Medicine. 174 (5): 655–662. doi: 10.7326/M20-6976. PMC 7839426. PMID 33481642. Exhaled respiratory particles can build-up within enclosed spaces with inadequate ventilation. The risk of COVID‑19 infection increases especially in spaces where people engage in physical exertion or raise their voice (e.g., exercising, shouting, singing) as this increases exhalation of respiratory droplets. Prolonged exposure to these conditions, typically more than 15 minutes, leads to higher risk of infection. [227]