Covid-19 Definition and 53 Discussions

Coronavirus disease 2019 (COVID-19) is a contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was identified in Wuhan, China in December 2019. The disease has since spread worldwide, leading to an ongoing pandemic.Symptoms of COVID-19 are variable, but often include fever, cough, headache, fatigue, breathing difficulties, and loss of smell and taste. Symptoms may begin one to fourteen days after exposure to the virus. At least a third of people who are infected do not develop noticeable symptoms. Of those people who develop noticeable symptoms enough to be classed as patients, most (81%) develop mild to moderate symptoms (up to mild pneumonia), while 14% develop severe symptoms (dyspnea, hypoxia, or more than 50% lung involvement on imaging), and 5% suffer critical symptoms (respiratory failure, shock, or multiorgan dysfunction). Older people are at a higher risk of developing severe symptoms. Some people continue to experience a range of effects (long COVID) for months after recovery, and damage to organs has been observed. Multi-year studies are underway to further investigate the long-term effects of the disease.Transmission of COVID-19 occurs when people are exposed to virus-containing respiratory droplets and airborne particles exhaled by an infected person. Those particles may be inhaled or may reach the mouth, nose, or eyes of a person through touching or direct deposition (i.e. being coughed on). The risk of infection is highest when people are in close proximity for a long time, but particles can be inhaled over longer distances, particularly indoors in poorly ventilated and crowded spaces. In those conditions small particles can remain suspended in the air for minutes to hours. Touching a contaminated surface or object may lead to infection although this does not contribute substantially to transmission. People who are infected can transmit the virus to another person up to two days before they themselves show symptoms, as can people who do not experience symptoms. People remain infectious for up to ten days after the onset of symptoms in moderate cases and up to twenty days in severe cases.Several testing methods have been developed to diagnose the disease. The standard diagnostic method is by detection of the virus' nucleic acid by real-time reverse transcription polymerase chain reaction (rRT-PCR), transcription-mediated amplification (TMA), or by reverse transcription loop-mediated isothermal amplification (RT-LAMP) from a nasopharyngeal swab.
Preventive measures include physical or social distancing, quarantining, ventilation of indoor spaces, covering coughs and sneezes, hand washing, and keeping unwashed hands away from the face. The use of face masks or coverings has been recommended in public settings to minimize the risk of transmissions.
While work is underway to develop drugs that inhibit the virus (and several vaccines for it have been approved and distributed in various countries, which have since initiated mass vaccination campaigns), the primary treatment is symptomatic. Management involves the treatment of symptoms, supportive care, isolation, and experimental measures.

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  1. Sagittarius A-Star

    COVID EMA review of COVID-19 Vaccine HIPRA - first bivalent (Alpha and Beta) recombinant Protein Vaccine

    Source: See also: Source:
  2. M

    What's going on with the COVID cases in Alabama?

    The CDC reports a 450% increase in Covid cases in Marengo County, Alabama ( ). The same thing is visible on New...
  3. Ygggdrasil

    COVID US Postal Service begins shipping free COVID tests

    Just an FYI to the American users of the forum: you can go to to order free at-home rapid antigen tests. (source: NPR) Unfortunately, the tests will likely arrive after the peak of the Omicron wave (or at least I hope Omicron is on the decline by the time the tests start...
  4. Sagittarius A-Star

    COVID Covid Variant B.1.640.2

    Source: Source:
  5. Sagittarius A-Star

    COVID Replication of SARS-CoV-2 in adipose tissue

    Replication of SARS-CoV-2 in adipose tissue determines organ and systemic lipid metabolism in hamsters and humans Source: Source (original German, quote via Google translate)...
  6. StevieTNZ

    COVID Covid Variant Omicron (B.1.1.529)
  7. Sagittarius A-Star

    COVID Electric field of moderate strength inactivates Covid-19 virus

    A science team from the university of Kassel (Germany) proved with a physical model, that a moderate electric field inactivates the Convid-19 virus. Source: via...
  8. E

    COVID Do virus masks actually work?

    Do virus masks have any effect on preventing or reducing risk of infection from CV19? Have there been any studies on this?
  9. Sagittarius A-Star

    COVID Short telomeres and severe COVID-19

    Not the numerical age directly, but the length of the telomeres seems to decide, if one gets severe COVID-19. Source: see also: Source:
  10. Sagittarius A-Star

    COVID Covid-19 mRNA/LNP Vaccine: understanding Biodistribution

    When mRNA/LNP vaccine gets injected into the upper arm (30 µg for BionTech/Pfizer, 100 µg for Moderna), small amounts get distributed to other organs. Source: Source...
  11. Ygggdrasil

    COVID COVID and the brain

    Here's a nice news piece from Nature summarizing various studies to find the underlying causes behind the neurological symptoms associated with COVID-19. In particular, the article highlights studies suggesting that SARS-CoV-2 can infect astrocytes in the brain, that SARS-CoV-2 can affect blood...
  12. T

    COVID Significant Loss of Brain Grey Matter after COVID-19 doi: Full PDF (32 pages) at:
  13. Evo

    COVID Covid Delta variant

    Get vaccinated!
  14. Ygggdrasil

    COVID SARS-CoV-2 Mutations

    Given the seeming increased transmissibility of the new SARS-CoV-2 variants being identified, I thought I'd start a general thread to collect and organize information on the various mutations to the SARS-CoV-2 virus. B.1.1.7 variant (aka 20B/501Y.V1, VOC 202012/01; originally identified in the...
  15. jim mcnamara

    COVID Vitamin D levels and Covid-19 [tl;dr[] : Change suggestions of Vitamin D supplementation in the UK - higher - the health officialdom just came down hard against Vitamin D supplementation increases of...
  16. Dale

    COVID Pfizer/Moderna covid vaccine research papers

    Here is the official peer reviewed Pfizer vaccine study published in the New England Journal of Medicine: This is a follow-up piece that describes what an emergency use authorization means and gives a perspective about follow-up...
  17. bhobba

    COVID Coronovirus Vaccine Progress

    We are starting to reach the stage when vaccines will be rolled out. I thought it was time to start a thread specifically on the state of play. Just an hour ago the following was published by an Australian newspaper (my precis): 'A vaccine will be available in Australia from the middle of...
  18. S

    Face shield bleach disinfection

    Faceshield or respirators are getting to be as common as masks in public. What kind of bleach in basin can theoretically kill the Covid virus? What should be the concentration of bleach and now does it kill it?
  19. U

    Admissions COVID-19 and Physics Graduate Admissions

    Several universities say that taking courses pass/no-pass or credit/no-credit during terms disrupted by COVID-19 will not necessarily harm those applying to their graduate program. There are also more open-ended invitations for applicants to discuss how the pandemic has impacted their lives. In...
  20. Andrew Mason

    COVID Remdesivir - a possible treatment for COVID-19?

    For anyone following Remdesivir as a treatment for COVID 19: this New England Journal of Medicine report on Gilead's remdesivir and this NIH/NCBI article explain how it works. The NIH paper has a nice chart showing how different drugs might interfere with viral replication. The recent phase 3...
  21. Wrichik Basu

    Efficacy of sanitizers against SARS-CoV-2 based on alcohol content

    Ethanol and 2-propanol (hereafter abbreviated "IPA") are the two alcohols that are used in hand-sanitizers. As per the standards set by WHO, the recommended levels are 80% (v/v) of ethanol and 75% (v/v) for IPA, along with other components like glycerol and hydrogen peroxide. Refer to the...
  22. mktsgm

    Is Sars-Cov2 cytolytic or cytopathic?

    We know viral infections result in cellular damage while they're replicating in the host cells.. Damage can be cytolytic or cytopathic. I want to know how Sars-cov2 causes such damage? Is it cytopathic or cytolytic? Do they (viruses) kill the host cells or just damage them?
  23. J

    Coronavirus reported cases/deaths pattern (why fewer on weekends?)

    Maybe this is a dumb question, but why are there fewer reported Covid-19 cases and deaths on weekends?
  24. jim mcnamara

    COVID Covid-19 in nursing homes- fatalities seem high New Mexico(USA) as of 29 April had 48 deaths out of 166 positive tests. All were nursing home patients, and a majority of the fatalities are clustered in two nursing home...
  25. neilparker62

    COVID Is low dose radiation therapy a potential treatment for COVID-19? What's the relevant science here ? Would just like to hear a bit more as to whether it holds out any meaningful prospects for treatment of Covid 19.
  26. Bob Walance

    People shaking hands with each other

    It would be interesting to see what the general consensus is regarding the future of the hand-shaking tradition between us humans. Please respond to the poll. Thanks.
  27. hagopbul

    Statistics of SARS-Cov-2

    Hello all: Hope all are fine and well , there is this question in relation to corona virus problem : Do anyone checked if the patients have any immunity related illnesses with the patients of SARS-Cov-2 Where I can find those statistics Best regards Stay safe
  28. Wrichik Basu

    COVID Asymptomatic COVID-19 cases

    Local and national authorities in India have stated that there is a rise in the number of asymptomatic COVID-19 cases. Around 80% of the cases are asymptomatic according to the Indian Council of Medical Research (ICMR). A news article mentioning the same can be found here...
  29. P

    Coronaviruses in Malayan pangolins

    " Here, we report the identification of SARS-CoV-2-related coronaviruses in Malayan pangolins (Manis javanica) seized in anti-smuggling operations in southern China. " How is it that Malayan pangolins would be tested at all for the China Virus? Is it common practice to examine any smuggled...
  30. W

    Disappearance of vapour trails - more warming?

    I think it was back around the 9-11 events that South African researchers happened to notice that solar radiation received at ground level increased by around 10% during the grounding of airline fleets world wide. If I remember correctly, this led to a measurable increase in plant growth over...
  31. T

    Medical ‘Possible Achilles heel’ in the coronavirus

    The folks at Scripps Institute and at The University of Hong Kong have found an antibody target on SARS-CoV-2 similar to the one on SARS-CoV (the 2002 SARS outbreak). They are looking for recovered COVID-19 volunteers, see bottom of this post or the San Diego Union article. The full article in...
  32. hagopbul

    COVID Covid-19 fatal effects

    Hello all: hope you are all well . as i am looking into reasons of death from Covid-19 i could see that pneumonia , is a major reason of death , but what kind of pneumonia ? i couldn't find on the internet is it only viral pneumonia or mix of types ? Best Hagop
  33. .Scott

    COVID COVID ARDS Diagnostic Tool - Age is not best indicator. N=53

    An article published Monday in "Computers, Materials, & Continua" identifies leading indicators of which patients will go on to develop ARDS (acute respiratory distress syndrome). From the abstract: Among the features identified as possible indicators: A pdf of the full article can be...
  34. B

    Is hydrogen peroxide effective against the corona virus?

    If oxygen is effective against bacteria virus and cancer why isn't it used against coved-19? DMSO is known to bond with certain substances and could carry HP into the blood stream and kill off COVID-19.
  35. jim mcnamara

    Policy for pandemic issues and how models shape it This shows how policy can be informed about differing effects of control policies in different environments. One of the bleak aspects of UK choices is shown as a graph...
  36. JD_PM

    COVID Are hydroxychloroquine and azithromycin the key against COVID-19?

    Hydroxychloroquine and azithromycin have been reported (By SEOM, Sociedad Española de Oncología Médica, by US President and others) to be a promising combination to treat COVID-19. A study leaded by French doctor Didier Raoult has yielded the following results: Why could such a...
  37. berkeman

    COVID Innovations to help COVID-19 treatment efforts

    I didn't see a thread so far in the Medical forum that addressed the specific innovations that are being worked on to help combat this pandemic, so I thought I'd start this thread. There is a thread about trying to use a single ventilator to serve multiple critical Patients (Pts) in ICU, but...
  38. berkeman

    Connecting 2-4 Patients to the Same Ventilator

    How does this work? Do you just parallel the tubing to the ET tubes? Or is there more to it? Seems like a risky move, but in these times, it may be necessary... From the link in the article...
  39. S

    COVID Covid-19 Prevention/Mitigation

    The goal is to 'flatten the curve' in terms the spread of Covid-19/corona virus. Hence, what about recommending effective gargling (3 times or more daily) with an anti-septic like Cepacol or Listerine (alcohol version) and going to the source of the problem, which is the throat/oro-pharynx? The...
  40. nomadreid

    Johns Hopkins Global Security Index

    I emphasize that I am not posing a rhetorical question, and am not trying to make a political statement (and would ask all respondents to steer clear of politics), but would genuinely appreciate knowing whether the report in question is considered valid by those in the field who are impartial...
  41. Grinkle

    COVID Effectiveness of early COVID-19 treatments

    Do we have data to give any perspective on these questions regarding COVID-19 victims - If a patient is deemed to need a respirator, what is the expected morbidity for them at that time if they are put on a respirator? I assume that without a respirator, the morbidity is close to 100%. Is...
  42. qnach

    I Nanoantennae calculation for covid-19

    Could anyone calculate the resonance frequencies of this molecule? The radius is about 50-200nm.
  43. K

    Coronavirus death toll estimations

    I was looking for projections on how many will die from the new virus. Unfortunately I found only this site but it is outdated as you can see. Perhaps it is because I'm not in the US? So that makes Google hide me a lot of...
  44. M

    Did any novels predict the effects of COVID-19?

    I've read number of virus disaster novels, but I can't recall any of them predicting anything like what's actually going on now. Anybody know of novels where the author predicted details such as a moderately lethal virus - so not end of the world stuff - leading to lock down and governments...
  45. Lnewqban

    What is a clinical ventilator?

    My apologies if already posted here or somewhere else. These articles are about what a clinical ventilator is, what problems improper use can cause and what parts are some people creating by 3-D printing:
  46. scottdave

    B Using a logarithmic scale to represent COVID-19 growth

    The author, John Burn-Murdoch, shows here ( ) how the logarithmic scale can give a better "sense" of what is happening. In linear scales, some countries' data is squashed to almost nonexistent, while others explode out of control. I...
  47. jim mcnamara

    Coronavirus infection rate + outcomes -versus bloodtypes This is a news report on a Chinese study, not a journal article Type O population of confirmed patients were disproportionately less like to die and less likely to become...
  48. BWV

    COVID >47% false positive rate on COVID-19 test?

    interesting: Objective: As the prevention and control of COVID-19continues to advance, the active nucleic acid test screening in the close contacts of the patients has been...
  49. A

    COVID Covid-19 virus disinfectant question -- Any aerosol options?

    I have a question both with regards to the current virus as well as to other potential diseases that are carried around in aerosol form, I have seen that commonly all hand sanitizers or sanitizers in general that use substances that are safe to humans use alcohol in some form. So I would presume...
  50. L

    Medical What makes the current coronavirus different from the others?

    An interview on NPR with virologists discussed the reasons that this current viral pandemic is different than others in the past. Key differences were: - Ability to make new viruses - apparently 1000 times more prolific than flu. - Unlike flu viruses, it does not appear to mutate because it...