COVID-19 Pandemic

The COVID-19 pandemic , also known as the coronavirus pandemic , is an ongoing pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), first identified in December 2019 in Wuhan, China. The World Health Organisation declared the outbreak a Public Health Emergency of International Concern in January 2020 and a pandemic in March 2020. As of 21 November 2020, more than 57.9   million cases have been confirmed, with more than 1.37   million deaths attributed to COVID-19. Common symptoms include fever, cough, fatigue, breathing difficulties, and loss of smell and taste. Complications may include pneumonia and acute respiratory distress syndrome. The incubation period is typically around five days but may range from one to 14 days. There are several vaccine candidates in development, although none has completed clinical trials. Although work is underway to develop drugs that inhibit the virus, the primary treatment is currentl...

For country-level data, see: COVID-19 pandemic by country and territory Cases 57,974,667 Deaths 1,378,411 As of 21 November 2020 Africa · Asia · Europe · North America Oceania · South America Background Although it is still unknown exactly where the outbreak first started, several early infected people had visited Huanan Seafood Wholesale Market, located in Wuhan, Hubei, China. On 11 February 2020, the World Health Organization (WHO) named the disease "COVID-19", which is short for coronavirus disease 2019. The virus that caused the outbreak is known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a newly discovered virus closely related to bat coronaviruses, pangolin coronaviruses, and SARS-CoV. The scientific consensus is that COVID-19 has a natural origin. The probable bat-to-human infection may have been among people processing bat carcasses and guano in the production of traditional Chinese medicines. The earliest known person with symptoms was la...

Symptoms of COVID-19 can be relatively non-specific; the two most common symptoms are fever (88 percent) and dry cough (68 percent). Less common symptoms include fatigue, respiratory sputum production (phlegm), loss of the sense of smell, loss of taste, shortness of breath, muscle and joint pain, sore throat, headache, chills, vomiting, coughing out blood, diarrhea, and rash. Among those who develop symptoms, approximately one in five may become more seriously ill and have difficulty breathing. Emergency symptoms include difficulty breathing, persistent chest pain or pressure, sudden confusion, difficulty waking, and bluish face or lips; immediate medical attention is advised if these symptoms are present. Further development of the disease can lead to complications including pneumonia, acute respiratory distress syndrome, sepsis, septic shock, and kidney failure.

Virology

COVID-19 can provisionally be diagnosed on the basis of symptoms and confirmed using reverse transcription polymerase chain reaction (RT-PCR) testing of infected secretions or CT imaging of the chest. On 29 September 2020, a letter in Lancet highlighted the increasing likelihood of overestimating of COVID-19 incidence as more asymptomatic people are included in RT-PCR testing with consequent "misdirection of policies regarding lockdowns and school closures," noting that the false-positive rate in the UK is currently unknown, with "preliminary estimates … somewhere between 0·8% and 4·0%". The letter called for "stricter standards … in laboratory testing, … and pretest probability assessments … including symptoms, previous medical history of COVID-19 or presence of antibodies, any potential exposure to COVID-19, and likelihood of an alternative diagnosis." Viral testing The standard test for presence of SARS-CoV-2 uses RNA testing of respiratory secretions c...

Strategies for preventing transmission of the disease include social distancing, wearing of masks, washing hands, avoiding touching the eyes, nose, or mouth with unwashed hands, and coughing or sneezing into a tissue, and putting the tissue directly into a waste container. Social distancing Social distancing (also known as physical distancing) includes infection control actions intended to slow the spread of the disease by minimising close contact between individuals. Methods include quarantines; travel restrictions; and the closing of schools, workplaces, stadiums, theatres, or shopping centres. Individuals may apply social distancing methods by staying at home, limiting travel, avoiding crowded areas, using no-contact greetings, and physically distancing themselves from others. Many governments are now mandating or recommending social distancing in regions affected by the outbreak. Non-cooperation with distancing measures in some areas has contributed to the further spread of the pan...

Screening, containment and mitigation Strategies in the control of an outbreak are screening, containment (or suppression), and mitigation. Screening is done with a device such as a thermometer to detect the elevated body temperature associated with fevers caused by the coronavirus. Containment is undertaken in the early stages of the outbreak and aims to trace and isolate those infected as well as introduce other measures to stop the disease from spreading. When it is no longer possible to contain the disease, efforts then move to the mitigation stage: measures are taken to slow the spread and mitigate its effects on the healthcare system and on society. A combination of both containment and mitigation measures may be undertaken at the same time. Suppression requires more extreme measures so as to reverse the pandemic by reducing the basic reproduction number to less than 1. Part of managing an infectious disease outbreak is trying to delay and decrease the epidemic peak, known as fla...

Antiviral medications are under investigation for COVID-19, though none have yet been shown to be clearly effective on mortality in published randomised controlled trials. Emergency use authorisation for remdesivir was granted in the U.S. on 1   May 2020, for people hospitalised with severe COVID-19. In September 2020, following a review of later research, the WHO recommended that remdesivir not be used for any cases of COVID-19, as there was no good evidence of benefit. In severe cases, the use of corticosteroids can reduce the risk of death. Taking over-the-counter cold medications, drinking fluids, and resting may help alleviate symptoms. Depending on the severity, oxygen therapy, intravenous fluids, and breathing support may be required. The safety and effectiveness of convalescent plasma as a treatment option requires further research. Other trials are investigating whether existing medications can be used effectively against COVID-19 or the immune reaction to it. On 16 June 2020,...

Some early studies suggest 10% to 20% of people with COVID-19 will experience symptoms lasting longer than a month. A majority of those who were admitted to hospital with severe disease report long-term problems including fatigue and shortness of breath. On 30 October 2020 WHO chief Tedros has warned that "to a significant number of people, the COVID virus poses a range of serious long-term effects". He has described the vast spectrum of COVID-19 symptoms that fluctuate over time as "really concerning." They range from fatigue, a cough and shortness of breath, to inflammation and injury of major organs – including the lungs and heart, and also neurological and psychologic effects. Symptoms often overlap and can affect any system in the body. Infected people have reported cyclical bouts of fatigue, headaches, months of complete exhaustion, mood swings and other symptoms. Tedros has underlined that therefore herd immunity is "morally unconscionable and unfeasible...

2019 Based on the retrospective analysis, starting from December 2019, the number of coronavirus cases in Hubei gradually increased, reaching 60 by 20 December and at least 266 by 31 December. That same day, the WHO received reports of a cluster of viral pneumonia cases of an unknown cause in Wuhan, and an investigation was launched at the start of January 2020. According to official Chinese sources, these early cases were mostly linked to the Huanan Seafood Wholesale Market, which also sold live animals. However, in May 2020, George Gao, the director of the Chinese Center for Disease Control and Prevention, said animal samples collected from the seafood market had tested negative for the virus, indicating the market was not the source of the initial outbreak. On 24 December 2019, Wuhan Central Hospital sent a bronchoalveolar lavage fluid (BAL) sample from an unresolved clinical case to sequencing company Vision Medicals. On 27 and 28 December, Vision Medicals informed the Wuhan Centra...

A total of 191 countries and territories have had at least one case of COVID-19 so far. Due to the pandemic in Europe, many countries in the Schengen Area have restricted free movement and set up border controls. National reactions have included containment measures such as quarantines and curfews (known as stay-at-home orders, shelter-in-place orders, or lockdowns). The WHO's recommendation on curfews and lockdowns is that they should be short-term measures to reorganize, regroup, rebalance resources, and protect health workers who are exhausted. To achieve a balance between restrictions and normal life, the long-term responses to the pandemic should consist of strict personal hygiene, effective contact tracing, and isolating when ill. By 26 March 2020, 1.7 billion people worldwide were under some form of lockdown, which increased to 3.9 billion people by the first week of April—more than half the world's population. By late April 2020, around 300 million people were under loc...

Travel restrictions As a result of the pandemic, many countries and regions imposed quarantines, entry bans, or other restrictions, either for citizens, recent travellers to affected areas, or for all travellers. Together with a decreased willingness to travel, this had a negative economic and social impact on the travel sector. Concerns have been raised over the effectiveness of travel restrictions to contain the spread of COVID-19. A study in Science found that travel restrictions had only modestly affected the initial spread of COVID-19, unless combined with infection prevention and control measures to considerably reduce transmissions. Researchers concluded that "travel restrictions are most useful in the early and late phase of an epidemic" and "restrictions of travel from Wuhan unfortunately came too late". The European Union rejected the idea of suspending the Schengen free travel zone and introducing border controls with Italy, a decision which has been cri...

Economics The outbreak is a major destabilising threat to the global economy. Agathe Demarais of the Economist Intelligence Unit has forecast that markets will remain volatile until a clearer image emerges on potential outcomes. One estimate from an expert at Washington University in St. Louis gave a $300+   billion impact on the world's supply chain that could last up to two years. Global stock markets fell on 24 February due to a significant rise in the number of COVID-19 cases outside China. On 27 February, due to mounting worries about the coronavirus outbreak, U.S. stock indexes posted their sharpest falls since 2008, with the Dow falling 1,191 points (the largest one-day drop since the financial crisis of 2007–08) and all three major indexes ending the week down more than 10 percent. On 28 February, Scope Ratings GmbH affirmed China's sovereign credit rating but maintained a Negative Outlook. Stocks plunged again due to coronavirus fears, the largest fall being on 16 Marc...