Search This Blog

Tuesday, March 10, 2020

Misinformation related to the 2019–20 coronavirus outbreak

From Wikipedia, the free encyclopedia

After the initial outbreak of coronavirus disease 2019 (COVID-19), conspiracy theories and misinformation spread online regarding the origin and scale, and various other aspects of the disease. Various social media posts claimed the virus was a bio-weapon with a patented vaccine, a population control scheme, or the result of a spy operation.

Efforts to combat misinformation

On 2 February, the World Health Organization (WHO) declared a "massive infodemic", citing an over-abundance of reported information, accurate and false, about the virus that "makes it hard for people to find trustworthy sources and reliable guidance when they need it." The WHO stated that the high demand for timely and trustworthy information has incentivised the creation of a direct WHO 24/7 myth-busting hotline where its communication and social media teams have been monitoring and responding to misinformation through its website and social media pages.

Facebook, Twitter and Google said they were working with WHO to address "misinformation". In a blogpost, Facebook stated they would remove content flagged by leading global health organizations and local authorities that violate its content policy on misinformation leading to "physical harm". Facebook are also giving free advertising to WHO.

At the end of February, Amazon banned over a million products that wrongly claimed to be able to cure or protect against coronavirus. They also removed tens of thousands of listings for overpriced health products.

Human made

Chinese biological weapon

In January 2020, the BBC published an article about coronavirus misinformation, citing two 24 January articles from the The Washington Times which claimed the virus was part of a Chinese biological weapons program, based at the Wuhan Institute of Virology (WIV). The Washington Post later published an article debunking the conspiracy theory, citing U.S. experts who explained why the Institute was not suitable for bioweapon research, that most countries had abandoned bioweapons as fruitless, and that there was no evidence that the virus was genetically engineered.

In February 2020, U.S. Senator Tom Cotton (R-AR) as well as Francis Boyle, a law professor, suggested that the virus may have been a Chinese bioweapon, while in the opinion of numerous medical experts there is no evidence for this. Conservative political commentator Rush Limbaugh said the virus was probably "a ChiCom laboratory experiment" and that the Chinese were weaponizing the virus and media hysteria surrounding it to bring down Donald Trump, on the most-listened-to radio show in US. In February 2020, The Financial Times reported from virus expert and global co-lead coronavirus investigator, Trevor Bedford, who said that "There is no evidence whatsoever of genetic engineering that we can find", and that, "The evidence we have is that the mutations [in the virus] are completely consistent with natural evolution". Bedford further explained, "The most likely scenario, based on genetic analysis, was that the virus was transmitted by a bat to another mammal between 20–70 years ago. This intermediary animal—not yet identified—passed it on to its first human host in the city of Wuhan in late November or early December 2019".

On 29 January, financial news website and blog ZeroHedge suggested, without evidence, that a scientist at the WIV created the COVID-19 strain responsible for the coronavirus outbreak. Zerohedge listed the full contact details of the scientist supposedly responsible, a practice known as doxing, by including the scientist's name, photo and phone number, suggesting to readers that they "pay [the Chinese scientist] a visit" if they wanted to know "what really caused the coronavirus pandemic". Twitter later permanently suspended the blog's account for violating its platform manipulation policy. Zerohedge has since claimed the article did not claim the virus was human-made and that it only publicised publicly available details of the scientist.


In January 2020, Buzzfeed News also reported on an internet meme/conspiracy theory of a link between the logo of the Wuhan Institute of Virology and "Umbrella Corporation", the agency that made the virus that starts the zombie apocalypse in the Resident Evil franchise. The theory also saw a link between "Racoon" (the main city in Resident Evil), and an anagram of "Corona" (the name of the virus). The popularity of this theory attracted the attention of Snopes, who proved it as false showing that the logo was not from the Institute, but from Shanghai Ruilan Bao Hu San Biotech Limited, located approximately 500 miles (800 km) away in Shanghai and additionally pointed out that the proper name of the city in Resident Evil is Raccoon City.

The Inverse reported that "Christopher Bouzy, the founder of Bot Sentinel, did a Twitter analysis for Inverse and found [online] bots and trollbots are making an array of false claims. These bots are claiming China intentionally created the virus, that it's a biological weapon, that Democrats are overstating the threat to hurt Donald Trump and more. While we can't confirm the origin of these bots, they are decidedly pro-Trump."

Misinformation aside, concerns on accidental leakage by the WIV remain. In 2017, U.S. molecular biologist Richard H. Ebright, expressed caution when the WIV was expanded to become mainland China's first biosafety level 4 (BSL–4) laboratory, noting previous escapes of the SARS virus at other Chinese laboratories. While Ebright refuted several conspiracy theories regarding the WIV (e.g. bioweapons research, that the virus was engineered), he told BBC China that this did not represent the possibility of the virus being "completely ruled out" from entering the population due to a laboratory accident. On 6 February, the White House asked scientists and medical researchers to rapidly investigate the origins of the virus in order to address both the current spread and "to inform future outbreak preparation and better understand animal/human and environmental transmission aspects of coronaviruses."

Tobias Elwood M.P. and Chairman of the British Defence Select Committee, also publicly questioned the role of the Chinese Army's Wuhan Institute for Biological Products and called for the "greater transparency over the origins of the coronavirus".

South China Morning Post reported that one of the Institute's lead researchers, Shi Zhengli, was the particular focus of personal attacks in Chinese social media who alleged her work on bat-based viruses as the source of the virus, leading Shi to post: "I swear with my life, [the virus] has nothing to do with the lab", and when asked by the SCMP to comment on the attacks, Shi responded: "My time must be spent on more important matters". Caixin reported Shi made further public statements against "perceived tinfoil-hat theories about the new virus's source", quoting her as saying: "The novel 2019 coronavirus is nature punishing the human race for keeping uncivilized living habits. I, Shi Zhengli, swear on my life that it has nothing to do with our laboratory".

US biological weapon

On 3 March, US Senator Marco Rubio, member of the Senate Select Committee on Intelligence and Committee on Foreign Relations, claimed that "malign actors in Beijing, Moscow, Tehran and elsewhere are exploiting the coronavirus pandemic to sow chaos through conspiracy theories – most heinously, the notion that the United States created the disease". He claimed that those states are "waging disinformation warfare over coronavirus".

Russian accusation

On 22 February, US officials alleged that Russia is behind an ongoing disinformation campaign, using thousands of social media accounts on Twitter, Facebook, Instagram to deliberately promote unfounded conspiracy theories, claiming that the virus is a biological weapon manufactured by the CIA and the US is waging economic war on China using the virus. The acting assistant secretary of state for Europe and Eurasia, Philip Reeker, said that "Russia's intent is to sow discord and undermine US institutions and alliances from within" and "by spreading disinformation about coronavirus, Russian malign actors are once again choosing to threaten public safety by distracting from the global health response". Russia denies the allegation, saying "this is a deliberately false story".

According to US-based The National Interest magazine, although official Russian channels had been muted on pushing the US biowarfare conspiracy theory, other Russian media elements don't share the Kremlin's restraint. Zvezda, a news outlet funded by the Russian Defense Ministry, published an article titled "Coronavirus: American biological warfare against Russia and China", claiming that the virus is intended to damage the Chinese economy, weakening its hand in the next round of trade negotiations. Ultra-nationalist politician and leader of the Liberal Democratic Party of Russia, Vladimir Zhirinovsky, claimed on a Moscow radio station that the virus was an experiment by the Pentagon and pharmaceutical companies. Politician Igor Nikulin made rounds on Russian television and news media, arguing that Wuhan was chosen for the attack because the presence of a BSL-4 virus lab provided a cover story for the Pentagon and CIA about a Chinese bio-experiment leak.

Iranian accusation

According to Radio Farda, Iranian cleric Seyyed Mohammad Saeedi accused US President Donald Trump of targeting Qom with coronavirus "to damage its culture and honor." Saeedi claimed that "by targeting Qom, Trump is fulfilling his promise of hitting Iranian cultural sites if Iranians took revenge for the U.S. killing of Quds Force Commander Qassem Soleimani.

Iranian researcher Ali Akbar Raefipour claimed that the coronavirus was part of a "hybrid warfare" programme waged by the United States on Iran and China.

Brigadier General Gholam Reza Jalali, head of Iranian Civil Defense Organization, claimed that the coronavirus is likely biological attack on China and Iran with economic goals.

Hossein Salami, the head of Islamic Revolutionary Guard Corps (IRGC), claimed that the coronavirus outbreak in Iran may be due to a US "biological attack".

Chinese accusation

According to London-based The Economist, conspiracy theories about COVID-19 being the CIA's creation to keep China down are all over the Chinese internet.

Multiple conspiracy articles in Chinese from SARS-era resurfaced during the outbreak with altered details, claiming that SARS is biological warfare conducted by America against China. Some of these articles claim that BGI Group from China sold genetic information of the Chinese race to America, with America then being able to deploy the virus specifically targeting the gene of Chinese individuals.

On 26 January, Chinese military news site Xilu published an article detailing how the virus was artificially combined by America to "precisely target Chinese people". The article was removed after early February.

Some articles on popular sites in Chinese have also cast suspicion on US military athletes participating in the Wuhan 2019 Military World Games which lasted until the end of October 2019 to have deployed the virus. They claim the inattentive attitude and disproportionately below average results of American athletes in the game indicate they might have been in for other purposes and they might actually be bio-warfare operatives, and that their place of residence during their stay in Wuhan was also close to the Huanan Seafood Wholesale Market, where the first known cluster of cases occurred.

Arab world

According to Washington D.C.-based nonprofit Middle East Media Research Institute, numerous writers in the Arabic press have promoted the conspiracy theory that COVID-19, as well as SARS and the swine flu virus, were deliberately created and spread by the US to make a profit on selling vaccines against these diseases, and it is "part of an economic and psychological war waged by the U.S. against China with the aim of weakening it and presenting it as a backward country and a source of diseases". Iraqi political analyst Sabah Al-Akili on Al-Etejah TV, Saudi daily Al-Watan writer Sa'ud Al-Shehry, Syrian daily Al-Thawra columnist Hussein Saqer, and Egyptian journalist Ahmad Rif'at on Egyptian news website Vetogate, were some examples given by MEMRI as the propagation of the US biowarfare conspiracy theory in the Arabic world.

Philippines

Filipino Senator, Tito Sotto, played a bioweapon conspiracy video in a February Senate hearing, suggesting that the coronavirus is biowarfare waged against China.

Spy operation

Some people have alleged that the coronavirus was stolen from a Canadian virus research lab by Chinese scientists, citing a news article by the Canadian Broadcasting Corporation (CBC) in July 2019. The CBC claimed their early report was distorted by misinformation, and that Eric Morrissette, chief of media relations for Health Canada and the Public Health Agency of Canada said that conspiracy theory had "no factual basis". Further, while the Chinese scientists had sent disease samples back to Beijing, neither sample sent during the 31 March 2019 transfer from Winnipeg, Canada to Beijing, China, was the current coronavirus. The current location of the missing Chinese researchers is confidential pending investigation by the Royal Canadian Mounted Police. There is also no publicly available proof that the missing Chinese scientists were responsible for sending the pathogens to China. In the midst of the coronavirus epidemic, a senior research associate and expert in biological warfare with the Begin-Sadat Center for Strategic Studies, referring to a NATO press conference, identified suspicions of espionage as the reason behind the expulsions from the lab, but made no suggestion that coronavirus was taken from the Canadian lab or that it is the result of bioweapons defense research in China.

Population control scheme

According to the BBC, Jordan Sather, a conspiracy theory YouTuber supporting the far-right QAnon conspiracy theory and the anti-vax movement, has falsely claimed the outbreak was a population control scheme created by Pirbright Institute in England, and by former Microsoft CEO Bill Gates.

Sam Hyde

A hoax post on Facebook claimed that Sam Hyde, who is described as an international biological weapons terrorist, was behind the outbreak. Hyde, a comedian, had previously been blamed for over a dozen mass shootings as part of a long-running meme.

Size of the outbreak

Nurse whistleblower

On 24 January, a video circulated online appearing to be of a nurse named Jin Hui in Hubei describing a far more dire situation in Wuhan than purported by Chinese officials. The video claimed that more than 90,000 people had been infected with the virus in China, the virus can spread from one person to 14 people and the virus is starting the second mutation. The video attracted millions of views on various social media platforms and was mentioned in numerous online reports. However, the BBC noted that contrary to its English subtitles in one of the video's existing versions, the woman does not claim to be either a nurse or a doctor in the video and that her suit and mask do not match the ones worn by medical staff in Hubei. The video's claim of 90,000 infected cases is noted to be 'unsubstantiated'.

Alleged leak of death toll

On 25 February, Taiwan News published an article, claiming Tencent accidentally leaked the real numbers of death and infection in China. Taiwan News suggests the Tencent Epidemic Situation Tracker had briefly showed infected cases and death tolls many times higher of the official figure, citing a Facebook post by 38-year-old Taiwanese beverage store owner Hiroki Lo and an anonymous Taiwanese netizen. The article was referenced by other news outlets such as Daily Mail and widely circulated on Twitter, Facebook, 4chan, sparked a wide range of conspiracy theories that the screenshot indicates the real death toll instead of the ones published by health officials. Justin Lessler, associate professor at the Bloomberg School of Public Health, claims the numbers of the alleged "leak" are unreasonable and unrealistic, citing the case fatality rate as far lower than the 'leaked information'. A spokesman of Tencent responded to the news article, claiming the image was doctored, and it features "false information which we never published".

Keoni Everington, author of the original news article, defended and asserted the authenticity of the leak.[61] Brian Hioe and Lars Wooster of New Bloom Magazine debunked the theory from data on other websites, which were using Tencent's database to generate custom visualizations while showing none of the inflated figures appearing in the images promulgated by Taiwan News. Thus, they concluded the screenshot was digitally fabricated.

Misinformation against Taiwan

On 26 February 2020, Taiwan Central News Agency reported large amount of misinformation has appeared on Facebook, claiming the epidemic in Taiwan has lost control, the Taiwanese Government was covering up the total number of cases, and the Taiwanese President Tsai Ing-wen had been infected. The Taiwan fact-check organization has suggests the misinformation on Facebook shares similarity of using simplified Chinese, mainland China vocabulary, and unconfirmed sources. Taiwan fact check organization warns the purpose of the misinformation is to attack the government.

In March 2020 Taiwan's Ministry of Justice Investigation Bureau warned that the People's Republic of China (PRC) was trying to undermine trust in factual news by portraying official Taiwanese Government reports as fake news. Taiwanese authorities are investigating whether these messages was linked to instructions given by the Communist Party. The PRC's Taiwan Affairs Office refuted the claims calling them lies and said that Taiwan's Democratic Progressive Party was "inciting hatred" between the two sides.

Vaccine and treatment

Vaccines existed

It was reported that multiple social media posts have promoted a conspiracy theory claiming the virus was known and that a vaccine was already available. PolitiFact and FactCheck.org noted that no vaccine currently exists for COVID-19. The patents cited by various social media posts reference existing patents for genetic sequences and vaccines for other strains of coronavirus such as the SARS coronavirus. The WHO reported as of 5 February 2020 that amid news reports of "breakthrough" drugs being discovered to treat people infected with the virus, there were no known effective treatments; this included antibiotics and herbal remedies not being useful.

Non-vaccine treatments

Traditional Chinese medicine

Chinese health authorities heavily promote the use of traditional Chinese medicine (TCM) against the disease. 

On 23 February 2020, Chinese president Xi Jinping called for enhanced usage of traditional Chinese medicine together with modern medicine on treating severe patients.

Various national and party-held media have heavily advertised a Wuhan Institute of Virology and Shanghai Institute of Materia Medica, Chinese Academy of Sciences report on how Shuanghuanglian, a herb mixture from traditional Chinese medicine, can effectively inhibit the novel coronavirus in an overnight research. The report has led to a buying crazes of the medicine. Despite voices of doubts, Shanghai Institute of Materia Medica confirm they, together with Wuhan Institute of Virology, have proven the medicine's effect on inhibiting the virus in vitro.

Jiangxia Fangcang temporary hospital, an emergency hospital in Wuhan set up to treat the novel coronavirus patients, have let their patients practice Chinese martial arts like Tai Chi and Ba Duan Jin (a form of Qigong) to improve their health.

India

Some politicians of India like Swami Chakrapani and Suman Haripriya claimed that drinking cow urine and applying cow dung on the body can cure coronavirus. WHO's chief scientist Soumya Swaminathan rubbished such claims and criticized these politicians for spreading misinformation.

Others

On 27 February 2020, the Estonian Minister of the Interior Mart Helme stated at a government press conference that the common cold had been renamed as the coronavirus and that in his youth nothing like that existed. He recommended wearing warm socks and mustard patches as well as spreading goose fat on one's chest as treatments for the virus. Helme also said that the virus would pass within a few days to a week just like the common cold.

Some QAnon proponents, including Jordan Stather, and others, have promoted gargling "Miracle Mineral Supplement" (actually an industrial bleach) as a way of preventing or curing the disease.

In February 2020, televangelist Jim Bakker promoted a colloidal silver solution sold on his website, as a remedy for coronavirus COVID-19; naturopath Sherrill Sellman, a guest on his show, falsely stated that it "hasn't been tested on this strain of the coronavirus, but it's been tested on other strains of the coronavirus and has been able to eliminate it within 12 hours."

Following the first reported case of COVID-19 in Nigeria on 28 February, untested cures and treatments began to spread via platforms like WhatsApp.

African resistance

Beginning on 11 February, reports, quickly spread via Facebook, implied that a Cameroonian student in China had been completely cured of the virus due to his African genetics. While a student was successfully treated, other media sources have noted that no evidence implies Africans are more resistant to the virus and labeled such claims as false information.

Misinformation by intergovernmental agencies

International Civil Aviation Organization

International Civil Aviation Organization (ICAO), a civil aviation agency that belongs to the United Nations, has rejected Taiwan's participation amid the novel coronavirus outbreak, which has affected Taiwan's ability to gather information from the international organization. In response to public inquiry on the organization's decision over social media platform Twitter, ICAO commented that their action is intended to "defend the integrity of the information". United Nations Secretary General have described those inquiry as an misinformation campaign targeting ICAO.

World Health Organization

The World Health Organization lists Taiwan as part of China, which resulted in multiple countries including Italy, Vietnam and the Philippines briefly banning flights from Taiwan in January and February 2020, despite the disease have not reached epidemic status in Taiwan during this period of time.

Misinformation by governments

China

Whistleblowing from various Chinese doctors, including Li Wenliang on 30 December 2019 revealed that Wuhan hospital authorities were already aware that the virus was a SARS-like coronavirus and patients were already placed under quarantine. However, news of the outbreak was also dismissed as "rumour mongering" by the Wuhan Public Security Bureau on 3 January 2020, with admonitions given to the individuals responsible. The Wuhan Health Commission still insisted that the illness spreading in Wuhan at the time was not SARS on 5 January 2020. An article published by a magazine owned by China News Service revealed that information had been suppressed during the beginning of the outbreak.

In the early stages of the outbreak, Chinese National Health Commission said that they had no "clear evidence" of human-to-human transmissions. Later research published on 20 January 2020 indicated that among officially confirmed cases, human-to-human transmission may have started in December of the previous year, and the delay of disclosure on the results until then, rather than earlier in January, was met with criticism towards health authorities. Wang Guangfa, one of the health officials, said that "There was uncertainty regarding the human-to-human transmission", but he was infected by a patient within 10 days of making the statement.

According to the Daily Beast, on 27 January, the editor of state-owned People's Daily tweeted an image of an apartment building and wrongly claimed that it was a hospital under construction in Wuhan, and that it have been completed "in 16 hours". The image was later retweeted by a deputy minister in China's Ministry of Foreign Affairs.

On 15 February 2020, China's paramount leader and party general secretary Xi Jinping published an article which claimed he had been aware of the epidemic since 7 January 2020 and issued an order to contain the spread of the disease during a meeting on that day. However, a record of that same meeting released beforehand shows that there was zero mention of the epidemic throughout.

United States

U.S. President Donald Trump and his top economic adviser Larry Kudlow have been accused of spreading misinformation about the coronavirus. On 25 February, Trump said, "I think that whole situation will start working out. We’re very close to a vaccine." In reality, SARS-CoV-2 has been "community-spreading" in the United States undetected for weeks, and new vaccine development may require a minimum of a year to prove safety and efficacy to gain regulatory approval. In an interview with Sean Hannity on 4 March, Trump also claimed that the death rate published by the WHO is false, that the potential impact of the outbreak is exaggerated by Democrats plotting against him, and that it is safe for infected individuals to go to work. In a later tweet, Trump denied he made claims regarding infected individuals going to work, despite footage from the interview.

The White House also has alleged the media has intentionally stoked fears of the virus to destabilize the administration. The Stat News reported that "President Trump and members of his administration have also said that U.S. containment of the virus is 'close to airtight' and that the virus is only as deadly as the seasonal flu. Their statements range from false to unproven, and in some cases, underestimate the challenges that public health officials must contend with in responding to the virus." About the same time that “airtight” claim was made, the first case of community spread of SARS-CoV-2 was confirmed, which is spreading faster than severe acute respiratory syndrome coronavirus with a case fatality rate at least seven times the fatality rate for seasonal flu.

In the first week of March, after the World Health Organization reported that the case fatality rate for COVID-19 increased from the previous estimate of around 2% to 3.4%, Trump baselessly claimed the correct fatality rate is less than 1%, and said, "Well, I think the 3.4% is really a false number."

Diet

Eating bats

Some media outlets, including Daily Mail and RT, and individuals spread misinformation by promoting a video showing a young Chinese woman biting into a bat, falsely suggesting it was shot in Wuhan and that the outbreak was due to locals eating bats. The widely circulated video features unrelated footage of Chinese travel vlogger Wang Mengyun eating bat soup in the island country Palau in 2016 as part of an online travel programme. Wang made an apology post on Weibo, where she revealed that she was inundated with abuse, such as death threats, and that she only wished to showcase local Palauan cuisine.

Eating meat

Some organizations and individuals, including PETA, made false claims on social media that eating meat made people susceptible to the virus. In India, a false rumour spread online alleging that only people who eat meat were affected by coronavirus, causing "#NoMeat_NoCoronaVirus" to trend on Twitter.

Misrepresented World Population Project map

In early February, a decade-old map illustrating a hypothetical viral outbreak published by the World Population Project (part of the University of Southampton) was misappropriated by a number of Australian media news outlets (including The Sun, Daily Mail and Metro) which claimed the map represented the 2020 coronavirus outbreak. This misinformation was then spread via the social media accounts of the same media outlets, and while some outlets later removed the map, the BBC reported that a number of news sites had not retracted the map yet.

Severe acute respiratory syndrome coronavirus 2

From Wikipedia, the free encyclopedia

Severe acute respiratory syndrome coronavirus 2
Electron micrograph of SARS-CoV-2 virions with visible coronae
Electron micrograph of SARS-CoV-2 virions with visible coronae
Illustration of a SARS-CoV-2 virion
Illustration of a SARS-CoV-2 virion
Virus classification e
(unranked): Virus
Realm: Riboviria
Phylum: incertae sedis
Order: Nidovirales
Family: Coronaviridae
Genus: Betacoronavirus
Subgenus: Sarbecovirus
Species:
Strain:
Severe acute respiratory syndrome coronavirus 2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), previously known by the provisional name 2019 novel coronavirus (2019-nCoV), is a positive-sense single-stranded RNA virus. It is contagious in humans and is the cause of the ongoing 2019–20 coronavirus outbreak, an epidemic of coronavirus disease 2019 (COVID-19) that has been designated a Public Health Emergency of International Concern by the World Health Organization (WHO).

SARS-CoV-2 has close genetic similarity to bat coronaviruses, from which it likely originated. An intermediate reservoir such as a pangolin is also thought to be involved in its introduction to humans. From a taxonomic perspective SARS-CoV-2 is classified as a strain of the species severe acute respiratory syndrome-related coronavirus (SARSr-CoV).

Because the strain was first discovered in Wuhan, China, it is sometimes referred to informally as the Wuhan coronavirus, although the World Health Organization (WHO) discourages the use of names based upon locations. To avoid confusion with the disease SARS, the WHO sometimes refers to the virus as "the virus responsible for COVID-19" in public health communications.

Virology

Infection

Human-to-human transmission of SARS-CoV-2 has been confirmed during the 2019–20 coronavirus outbreak. Transmission occurs primarily via respiratory droplets from coughs and sneezes within a range of about 6 feet (1.8 m). Indirect contact via contaminated surfaces is another possible cause of infection. Viral RNA has also been found in stool samples from infected patients.

It is possible that the virus can be infectious even during the incubation period, but this has not been proven, and the World Health Organization (WHO) stated on 1 February 2020 that "transmission from asymptomatic cases is likely not a major driver of transmission" at this time. Thus, most infections in humans are believed to be the result of transmission from subjects exhibiting symptoms of coronavirus disease 2019.

Reservoir

The first known infections from the SARS-CoV-2 strain were discovered in Wuhan, China. The original source of viral transmission to humans remains unclear. However, research into the origin of the 2003 SARS outbreak has resulted in the discovery of many SARS-like bat coronaviruses, most originating in the Rhinolophus genus of horseshoe bats. Two viral nucleic acid sequences found in samples taken from Rhinolophus sinicus show a resemblance of 80% to SARS-CoV-2. A third viral nucleic acid sequence from Rhinolophus affinis collected in Yunnan province has a 96% resemblance to SARS-CoV-2. The WHO considers bats the most likely natural reservoir of SARS-CoV-2.

A metagenomic study published in 2019 previously revealed that SARS-CoV, the strain of the virus that causes SARS, was the most widely distributed coronavirus among a sample of Malayan pangolins. On 7 February 2020, it was announced that researchers from Guangzhou had discovered a pangolin sample with a viral nucleic acid sequence "99% identical" to SARS-CoV-2. When released, the results clarified that "the receptor-binding domain of the S protein of the newly discovered Pangolin-CoV is virtually identical to that of 2019-nCoV, with one amino acid difference." Pangolins are protected under Chinese law, but their poaching and trading for use in traditional Chinese medicine remains common.

Microbiologists and geneticists in Texas have independently found evidence of reassortment in coronaviruses suggesting the involvement of pangolins in the origin of SARS-CoV-2. They acknowledged remaining unknown factors while urging continued examination of other mammals.

Phylogenetics and taxonomy

Genomic information
SARS-CoV-2 genome.svg
Genomic organisation of isolate Wuhan-Hu-1, the earliest sequenced sample of SARS-CoV-2
NCBI genome IDMN908947
Genome size29,903 bases
Year of completion2020

SARS-CoV-2 belongs to the broad family of viruses known as coronaviruses. It is a positive-sense single-stranded RNA (+ssRNA) virus. Other coronaviruses are capable of causing illnesses ranging from the common cold to more severe diseases such as Middle East respiratory syndrome (MERS). It is the seventh known coronavirus to infect people, after 229E, NL63, OC43, HKU1, MERS-CoV, and the original SARS-CoV.

Like the SARS-related coronavirus strain implicated in the 2003 SARS outbreak, SARS-CoV-2 is a member of the subgenus Sarbecovirus (beta-CoV lineage B). Its RNA sequence is approximately 30,000 bases in length. SARS-CoV-2 is unique among known betacoronaviruses in its incorporation of a polybasic cleavage site, a characteristic known to increase pathogenicity and transmissibility in other viruses.

With a sufficient number of sequenced genomes, it is possible to reconstruct a phylogenetic tree of the mutation history of a family of viruses. By 12 January 2020, five genomes of SARS-CoV-2 had been isolated from Wuhan and reported by the Chinese Center for Disease Control and Prevention (CCDC) and other institutions; the number of genomes increased to 81 by 11 February 2020. A phylogenetic analysis of those samples showed they were "highly related with at most seven mutations relative to a common ancestor", implying that the first human infection occurred in November or December 2019.

On 11 February 2020, the International Committee on Taxonomy of Viruses (ICTV) announced that according to existing rules that compute hierarchical relationships among coronaviruses on the basis of five conserved sequences of nucleic acids, the differences between what was then called 2019-nCoV and the virus strain from the 2003 SARS outbreak were insufficient to make it a separate viral species. Therefore, they identified 2019-nCoV as a strain of severe acute respiratory syndrome-related coronavirus.

Structural biology

SARS-CoV-2 emerging from a human cell
SARS-CoV-2 emerging from a human cell
Digitally colourized electron micrographs of SARS-CoV-2 (yellow) emerging from human cells
 
Each SARS-CoV-2 virion is approximately 50–200 nanometres in diameter. Like other coronaviruses, SARS-CoV-2 has four structural proteins, known as the S (spike), E (envelope), M (membrane), and N (nucleocapsid) proteins; the N protein holds the RNA genome, and the S, E, and M proteins together create the viral envelope. The spike protein is responsible for allowing the virus to attach to the membrane of a host cell.

Protein modeling experiments on the spike protein of the virus soon suggested that SARS-CoV-2 has sufficient affinity to the angiotensin converting enzyme 2 (ACE2) receptors of human cells to use them as a mechanism of cell entry. By 22 January 2020, a group in China working with the full virus genome and a group in the United States using reverse genetics methods independently and experimentally demonstrated that ACE2 could act as the receptor for SARS-CoV-2. Studies have shown that SARS-CoV-2 has a higher affinity to human ACE2 than the original SARS virus strain. An atomic-level image of the S protein has been created using cryogenic electron microscopy.

SARS-Cov-2 produces at least three virulence factors that promote dissemination of new virions from host cells and inhibit immune response.

Epidemiology

Based upon the low variability exhibited among known SARS-CoV-2 genomic sequences, the strain is thought to have been detected by health authorities within weeks of its emergence among the human population in late 2019. The virus subsequently spread to all provinces of China and to more than one hundred other countries in Asia, Europe, North America, South America, Africa, and Oceania. Human-to-human transmission of the virus has been confirmed in all of these regions. On 30 January 2020, SARS-CoV-2 was designated a Public Health Emergency of International Concern by the WHO.

As of 9 March 2020 (22:40 UTC), there were 113,584 confirmed cases of infection, of which 80,735 were within mainland China. While the proportion of infections that result in confirmed infection or progress to diagnosable disease remains unclear, one mathematical model estimated the number of people infected in Wuhan alone at 75,815 as of 25 January 2020, at a time when confirmed infections were far lower. The total number of deaths attributed to the virus was 3,996 as of 9 March 2020 (22:40 UTC). Over 75% of all deaths have occurred in Hubei province, where Wuhan is located.

The basic reproduction number () of the virus has been estimated to be between 1.4 and 3.9. This means that each infection from the virus is expected to result in 1.4 to 3.9 new infections when no preventive measures are taken.

Coronavirus

From Wikipedia, the free encyclopedia

Orthocoronavirinae
Coronaviruses 004 lores.jpg
Electron micrograph of avian infectious bronchitis virus
2019-nCoV-CDC-23312 without background.png
Illustration of the morphology of coronaviruses; the club-shaped viral spike peplomers, coloured red, create the look of a corona surrounding the virion, when viewed electron microscopically
Virus classification e
(unranked): Virus
Realm: Riboviria
Phylum: incertae sedis
Order: Nidovirales
Family: Coronaviridae
Subfamily: Orthocoronavirinae
Genera
Synonyms
  • Coronavirinae

Coronaviruses are a group of viruses that cause diseases in mammals and birds. In humans, coronaviruses cause respiratory tract infections that are typically mild, such as some cases of the common cold (among other possible causes, predominantly rhinoviruses), though rarer forms can be lethal, such as SARS, MERS, and COVID-19. Symptoms vary in other species: in chickens, they cause an upper respiratory tract disease, while in cows and pigs they cause diarrhea. There are yet to be vaccines or antiviral drugs to prevent or treat human coronavirus infections.

Coronaviruses constitute the subfamily Orthocoronavirinae, in the family Coronaviridae, order Nidovirales, and realm Riboviria. They are enveloped viruses with a positive-sense single-stranded RNA genome and a nucleocapsid of helical symmetry. The genome size of coronaviruses ranges from approximately 27 to 34 kilobases, the largest among known RNA viruses. The name coronavirus is derived from the Latin corona, meaning "crown" or "halo", which refers to the characteristic appearance reminiscent of a crown or a solar corona around the virions (virus particles) when viewed under two-dimensional transmission electron microscopy, due to the surface covering in club-shaped protein spikes.

Discovery

Coronaviruses were first discovered in the 1960s. The earliest ones discovered were infectious bronchitis virus in chickens and two viruses from the nasal cavities of human patients with the common cold that were subsequently named human coronavirus 229E and human coronavirus OC43. Other members of this family have since been identified, including SARS-CoV in 2003, HCoV NL63 in 2004, HKU1 in 2005, MERS-CoV in 2012, and SARS-CoV-2 (formerly known as 2019-nCoV) in 2019. Most of these have involved serious respiratory tract infections.

Name and morphology

The name "coronavirus" is derived from Latin corona, meaning "crown" or "wreath", itself a borrowing from Greek κορώνη korṓnē, "garland, wreath". The name refers to the characteristic appearance of virions (the infective form of the virus) by electron microscopy, which have a fringe of large, bulbous surface projections creating an image reminiscent of a crown or of a solar corona. This morphology is created by the viral spike (S) peplomers, which are proteins on the surface of the virus that determines host tropism.

Proteins that contribute to the overall structure of all coronaviruses are the spike (S), envelope (E), membrane (M), and nucleocapsid (N). In the specific case of the SARS coronavirus (see below), a defined receptor-binding domain on S mediates the attachment of the virus to its cellular receptor, angiotensin-converting enzyme 2 (ACE2). Some coronaviruses (specifically the members of Betacoronavirus subgroup A) also have a shorter spike-like protein called hemagglutinin esterase (HE).

Replication

The infection cycle of a coronavirus

After entry into the host cell, the virus particle is uncoated, and its genome enters the cell cytoplasm.

The coronavirus RNA genome has a 5′ methylated cap and a 3′ polyadenylated tail, which allows the RNA to attach to the host cell's ribosome for translation. The host ribosome translates the initial overlapping open reading frame of the virus genome and forms a long polyprotein. The polyprotein has its own proteases which cleave the polyprotein into multiple nonstructural proteins.

A number of the nonstructural proteins coalesce to form a multi-protein replicase-transcriptase complex (RTC). The main replicase-transcriptase protein is the RNA-dependent RNA polymerase (RdRp). It is directly involved in the replication and transcription of RNA from an RNA strand. The other nonstructural proteins in the complex assist in the replication and transcription process. The exoribonuclease non-structural protein for instance provides extra fidelity to replication by providing a proofreading function which the RNA-dependent RNA polymerase lacks.

One of the main functions of the complex is to replicate the viral genome. RdRp directly mediates the synthesis of negative-sense genomic RNA from the positive-sense genomic RNA. This is followed by the replication of positive-sense genomic RNA from the negative-sense genomic RNA. The other important function of the complex is to transcribe the viral genome. RdRp directly mediates the synthesis of negative-sense subgenomic RNA molecules from the positive-sense genomic RNA. This is followed by the transcription of these negative-sense subgenomic RNA molecules to their corresponding positive-sense mRNAs.

The replicated positive-sense genomic RNA becomes the genome of the progeny viruses. The mRNAs are gene transcripts of the last third of the virus genome after the initial overlapping reading frame. These mRNAs are translated by the host's ribosomes into the structural proteins and a number of accessory proteins. RNA translation occurs inside the endoplasmic reticulum. The viral structural proteins S, E, and M move along the secretory pathway into the Golgi intermediate compartment. There, the M proteins direct most protein-protein interactions required for assembly of viruses following its binding to the nucleocapsid. Progeny viruses are then released from the host cell by exocytosis through secretory vesicles.

Transmission

Human to human transmission of coronaviruses is primarily thought to occur among close contacts via respiratory droplets generated by sneezing and coughing.

Taxonomy

Phylogenetic tree of coronaviruses

The scientific name for coronavirus is Orthocoronavirinae or Coronavirinae. Coronavirus belongs to the family of Coronaviridae.

Evolution

The most recent common ancestor (MRCA) of all coronaviruses has been placed at around 8000 BCE. The MRCAs of the Alphacoronavirus line has been placed at about 2400 BCE, the Betacoronavirus line at 3300 BCE, the Gammacoronavirus line at 2800 BCE, and the Deltacoronavirus line at about 3000 BCE. It appears that bats and birds, as warm-blooded flying vertebrates, are ideal hosts for the coronavirus gene source (with bats for Alphacoronavirus and Betacoronavirus, and birds for Gammacoronavirus and Deltacoronavirus) to fuel coronavirus evolution and dissemination.

Bovine coronavirus and canine respiratory coronaviruses diverged from a common ancestor in 1951. Bovine coronavirus and human coronavirus OC43 diverged around the 1890s. Bovine coronavirus diverged from the equine coronavirus species at the end of the 18th century.

The MRCA of human coronavirus OC43 has been dated to the 1950s.

MERS-CoV, although related to several bat coronavirus species, appears to have diverged from these several centuries ago. The human coronavirus NL63 and a bat coronavirus shared an MRCA 563–822 years ago.

The most closely related bat coronavirus and SARS-CoV diverged in 1986. A path of evolution of the SARS virus and keen relationship with bats have been proposed. The authors suggest that the coronaviruses have been coevolved with bats for a long time and the ancestors of SARS-CoV first infected the species of the genus Hipposideridae, subsequently spread to species of the Rhinolophidae and then to civets, and finally to humans.

Alpaca coronavirus and human coronavirus 229E diverged before 1960.

Human coronaviruses

Cross-sectional model of a coronavirus
Cross-sectional model of a coronavirus

Coronaviruses vary significantly in risk factor. Some can kill more than 30% of those infected (such as MERS-CoV), and some are relatively harmless, such as the common cold. Coronaviruses cause colds with major symptoms, such as fever and sore throat from swollen adenoids, primarily in the winter and early spring seasons. Coronaviruses can cause pneumonia – either direct viral pneumonia or a secondary bacterial pneumonia – and may cause bronchitis – either direct viral bronchitis or a secondary bacterial bronchitis. The much publicized human coronavirus discovered in 2003, SARS-CoV, which causes severe acute respiratory syndrome (SARS), has a unique pathogenesis because it causes both upper and lower respiratory tract infections.

Seven strains of human coronaviruses are known:
  1. Human coronavirus 229E (HCoV-229E)
  2. Human coronavirus OC43 (HCoV-OC43)
  3. Severe acute respiratory syndrome coronavirus (SARS-CoV)
  4. Human coronavirus NL63 (HCoV-NL63, New Haven coronavirus)
  5. Human coronavirus HKU1
  6. Middle East respiratory syndrome-related coronavirus (MERS-CoV), previously known as novel coronavirus 2012 and HCoV-EMC
  7. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), previously known as 2019-nCoV or "novel coronavirus 2019"
The coronaviruses HCoV-229E, -NL63, -OC43, and -HKU1 continually circulate in the human population and cause respiratory infections in adults and children world-wide.

Outbreaks of coronavirus-related diseases

Outbreaks of coronavirus types of relatively high mortality are as follows:

Outbreak Virus type Deaths
2003 severe acute respiratory syndrome outbreak SARS-CoV 774
2012 Middle East respiratory syndrome coronavirus outbreak MERS-CoV Over 400
2015 Middle East respiratory syndrome outbreak in South Korea MERS-CoV 36
2018 Middle East respiratory syndrome outbreak MERS-CoV 41
2019–20 coronavirus outbreak SARS-CoV-2 ~4000

Severe acute respiratory syndrome (SARS)

In 2003, following the outbreak of severe acute respiratory syndrome (SARS) which had begun the prior year in Asia, and secondary cases elsewhere in the world, the World Health Organization (WHO) issued a press release stating that a novel coronavirus identified by a number of laboratories was the causative agent for SARS. The virus was officially named the SARS coronavirus (SARS-CoV). Over 8,000 people were infected, about 10% of whom died.

Middle East respiratory syndrome (MERS)

In September 2012, a new type of coronavirus was identified, initially called Novel Coronavirus 2012, and now officially named Middle East respiratory syndrome coronavirus (MERS-CoV). The World Health Organization issued a global alert soon after. The WHO update on 28 September 2012 stated that the virus did not seem to pass easily from person to person. However, on 12 May 2013, a case of human-to-human transmission in France was confirmed by the French Ministry of Social Affairs and Health. In addition, cases of human-to-human transmission were reported by the Ministry of Health in Tunisia. Two confirmed cases involved people who seemed to have caught the disease from their late father, who became ill after a visit to Qatar and Saudi Arabia. Despite this, it appears that the virus had trouble spreading from human to human, as most individuals who are infected do not transmit the virus. By 30 October 2013, there were 124 cases and 52 deaths in Saudi Arabia.

After the Dutch Erasmus Medical Centre sequenced the virus, the virus was given a new name, Human Coronavirus–Erasmus Medical Centre (HCoV-EMC). The final name for the virus is Middle East respiratory syndrome coronavirus (MERS-CoV). In May 2014, the only two United States cases of MERS-CoV infection were recorded, both occurring in healthcare workers who worked in Saudi Arabia and then travelled to the U.S. One was treated in Indiana and one in Florida. Both of these individuals were hospitalized temporarily and then discharged.

In May 2015, an outbreak of MERS-CoV occurred in the Republic of Korea, when a man who had traveled to the Middle East, visited 4 hospitals in the Seoul area to treat his illness. This caused one of the largest outbreaks of MERS-CoV outside the Middle East. As of December 2019, 2,468 cases of MERS-CoV infection had been confirmed by laboratory tests, 851 of which were fatal, a mortality rate of approximately 34.5%.

Coronavirus disease 2019 (COVID-19)


In December 2019, a pneumonia outbreak was reported in Wuhan, China. On 31 December 2019, the outbreak was traced to a novel strain of coronavirus, which was given the interim name 2019-nCoV by the World Health Organization (WHO), later renamed SARS-CoV-2 by the International Committee on Taxonomy of Viruses. Some researchers have suggested that the Huanan Seafood Market may not be the original source of viral transmission to humans.

As of 9 March 2020, there have been at least 3,996 confirmed deaths and more than 113,584 confirmed cases in the coronavirus pneumonia outbreak. The Wuhan strain has been identified as a new strain of Betacoronavirus from group 2B with approximately 70% genetic similarity to the SARS-CoV. The virus has a 96% similarity to a bat coronavirus, so it is widely suspected to originate from bats as well. The pandemic has resulted in serious restrictions over travel.

Other animals

Coronaviruses have been recognized as causing pathological conditions in veterinary medicine since the early 1970s. Except for avian infectious bronchitis, the major related diseases have mainly an intestinal location.

Diseases caused

Coronaviruses primarily infect the upper respiratory and gastrointestinal tract of mammals and birds. They also cause a range of diseases in farm animals and domesticated pets, some of which can be serious and are a threat to the farming industry. In chickens, the infectious bronchitis virus (IBV), a coronavirus, targets not only the respiratory tract but also the urogenital tract. The virus can spread to different organs throughout the chicken. Economically significant coronaviruses of farm animals include porcine coronavirus (transmissible gastroenteritis coronavirus, TGE) and bovine coronavirus, which both result in diarrhea in young animals. Feline coronavirus: two forms, feline enteric coronavirus is a pathogen of minor clinical significance, but spontaneous mutation of this virus can result in feline infectious peritonitis (FIP), a disease associated with high mortality. Similarly, there are two types of coronavirus that infect ferrets: Ferret enteric coronavirus causes a gastrointestinal syndrome known as epizootic catarrhal enteritis (ECE), and a more lethal systemic version of the virus (like FIP in cats) known as ferret systemic coronavirus (FSC). There are two types of canine coronavirus (CCoV), one that causes mild gastrointestinal disease and one that has been found to cause respiratory disease. Mouse hepatitis virus (MHV) is a coronavirus that causes an epidemic murine illness with high mortality, especially among colonies of laboratory mice. Sialodacryoadenitis virus (SDAV) is highly infectious coronavirus of laboratory rats, which can be transmitted between individuals by direct contact and indirectly by aerosol. Acute infections have high morbidity and tropism for the salivary, lachrymal and harderian glands.

A HKU2-related bat coronavirus called swine acute diarrhea syndrome coronavirus (SADS-CoV) causes diarrhea in pigs.

Prior to the discovery of SARS-CoV, MHV had been the best-studied coronavirus both in vivo and in vitro as well as at the molecular level. Some strains of MHV cause a progressive demyelinating encephalitis in mice which has been used as a murine model for multiple sclerosis. Significant research efforts have been focused on elucidating the viral pathogenesis of these animal coronaviruses, especially by virologists interested in veterinary and zoonotic diseases.

In domestic animals

Genomic cis-acting elements

In common with the genomes of all other RNA viruses, coronavirus genomes contain cis-acting RNA elements that ensure the specific replication of viral RNA by a virally encoded RNA-dependent RNA polymerase. The embedded cis-acting elements devoted to coronavirus replication constitute a small fraction of the total genome, but this is presumed to be a reflection of the fact that coronaviruses have the largest genomes of all RNA viruses. The boundaries of cis-acting elements essential to replication are fairly well-defined, and the RNA secondary structures of these regions are understood. However, how these cis-acting structures and sequences interact with the viral replicase and host cell components to allow RNA synthesis is not well understood.

Genome packaging

The assembly of infectious coronavirus particles requires the selection of viral genomic RNA from a cellular pool that contains an abundant excess of non-viral and viral RNAs. Among the seven to ten specific viral mRNAs synthesized in virus-infected cells, only the full-length genomic RNA is packaged efficiently into coronavirus particles. Studies have revealed cis-acting elements and trans-acting viral factors involved in the coronavirus genome encapsidation and packaging. Understanding the molecular mechanisms of genome selection and packaging is critical for developing antiviral strategies and viral expression vectors based on the coronavirus genome.

Butane

From Wikipedia, the free encyclopedia ...