Does the novel coronavirus (SARS-CoV-2) come from humans killing animals?

Updated 1 June 2020

Short answer: At the moment we don't know. But if I had to guess, I would guess: yes.

Longer answer:
Zoonotic diseases or zoonoses are "trans-species" diseases. Typically when talking about zoonoses people mean diseases in humans that have come from non-human animals.

Very many of our current diseases have come from non-human animals. For example, quite surely the following: 
  • Ebola
  • AIDS
  • measles
  • smallpox
  • typhoid fever
  • whooping cough (pertussis)
  • flu (influenza)
  • tapeworm infections
  • the common cold
  • leprosy
  • Helicobacter pylori infection
  • variant Creutzfeldt-Jakob disease (from BSE)
  • Nipah virus infection
  • Junín virus infection
  • Streptococcus suis infection
  • Marburg virus infection
  • Rift Valley fever
  • Hendra virus infection
  • SARS (caused by SARS-CoV)
  • Middle East respiratory syndrome (caused by MERS-CoV)
  • etc.
... and now maybe the new coronavirus that doesn't have a proper name yet and which causes the so far somewhat weirdly named disease COVID-19 (Coronavirus disease 2019).

Vegans (including me) like to point out that factory farms (and other ways of animal killing, including animal experiments and killing of animals in nature) can be a potential source of creating new zoonotic diseases that affect humans. The novel coronavirus doesn't seem to have come from a factory farm. But maybe it came from humans selling and/or killing animals ("wildlife") ...

"Nearly 75% of all emerging infectious diseases (EIDs) that impact or threaten human health are zoonotic. The majority have spilled from wildlife reservoirs, either directly to humans or via domestic animals. The emergence of many can be attributed to predisposing factors such as global travel, trade, agricultural expansion, deforestation/habitat fragmentation, and urbanization; such factors increase the interface and/or the rate of contact between human, domestic animal, and wildlife populations, thereby creating increased opportunities for spillover events to occur. [...] Nipah virus in Malaysia in 1999 and severe acute respiratory syndrome (SARS) in China in 2003 provide useful case studies. The emergence of Nipah virus was associated with the increased size and density of commercial pig farms and their encroachment into forested areas. The movement of pigs for sale and slaughter in turn led to the rapid spread of infection to southern peninsular Malaysia, where the high-density, largely urban pig populations facilitated transmission to humans. [...] Emerging infectious diseases originating from wildlife populations will continue to threaten public health. Mitigating and managing the risk requires an appreciation of the connectedness between human, livestock and wildlife health, and of the factors and processes that disrupt the balance." (Field 2009)

"This is the third serious Coronavirus outbreak in less than 20 years, following SARS in 2002-2003 and MERS in 2012." (Yang et al. 2020)

What is the new coronavirus really called?
  • So far there is no proper name. The following names have been used: "coronavirus", novel coronavirus, 2019-nCov, SARS-Cov-2. SARS-CoV-2 is (currently) the "official" name (Yang et al. 2020) ... Maybe it will be called Wuhan virus one day.

Is it sure that the new coronavirus (SARS-CoV-2) came from non-human animals, i.e. that this virus is zoonotic?

Where did the new coronavirus come from?
  • Probably from Wuhan (Hubei Province, China). This is where the first cases were reported (Huang et al. 2020).

But where exactly in Wuhan did it start?

Which animal species did the new coronavirus likely come from?
  • Probably from bats (Ceraolo and Giorgi 2020Chan et al. 2020, Guo et al. 2020Ji et al. 2020, Liu et al. 2020 bLu et al. 2020, Rabi et al. 2020Rehman et al. 2020Wan et al. 2020Yang et al. 2020, Zhao 2020).
  • A potential original carrier of the novel coronavirus is the bat species "intermediate horseshoe bat" (Rhinolophus affinis) (Yang et al. 2020) - but other bat species are possible: See "Info box: use of bats in Traditional Chinese Medicine" at the end.
  • Interestingly, "[...] the outbreak was first reported in late December, 2019, when most bat species in Wuhan are hibernating." (Lu et al. 2020)
  • Probably there was an intermediate animal species (Lu et al. 2020) - between bats and humans - but it's not sure what the intermediate animal species was.
  • "Currently available data suggest that 2019-nCoV infected the human population from a bat reservoir, although it remains unclear if a currently unknown animal species acted as an intermediate host between bats and humans." (Lu et al. 2020)
  • It seems that the new coronavirus is "a recombinant virus between the bat coronavirus and an origin‐unknown coronavirus." (Ji et al. 2020)
  • Possibly the intermediate animal species were: "currently unknown wild animal(s) sold at the Huanan seafood market" (Lu et al. 2020)
  • “Although [...] bats might be the original host of this virus, an animal sold at the seafood market in Wuhan might represent an intermediate host facilitating the emergence of the virus in humans." (Lu et al. 2020)
  • The unknown coronavirus might have something to do with snakes (Ji et al. 2020), i.e. the unknown species might be a snake.
  • Another possibility is that pangolins might be the intermediate unknown species: "Researchers found that the SARS-CoV-2 showed a higher sequence homology to Bat-CoV-RaTG13 that was previously detected in Rhinolophus affinis from Yunnan Province than Bat-SL-CoVZC21 and Bat-SL-CoVZC45, which suggested that the Chinese chrysanthemum bat is the origin of SARS-CoV-2. More recently, the pangolin was believed to be the likely intermediate host due to the fact that there appeared to be approximately 99% sequence homology between SARS-Co V-2 and the consensus sequence derived from >1000 metagenomic samples from the pangolin species". (Yang et al. 2020).
  • But there is also doubt that the virus could have really directly spread from pangolins to humans: "Therefore, we concluded that the human SARS-CoV-2 virus, which is responsible for the recent outbreak of COVID-19, did not come directly from pangolins." (Li et al. 2020)
  • Yet another potential intermediate host are turtles (Chrysemys picta bellii, Chelonia mydas, and/or Pelodiscus sinensis): "Compared with the illegally traded pangolins, turtles in the markets are more common and popular." (Liu et al. 2020).
  • The SARS-CoV-2 virus has been described as being closely related to but not the same as other coronaviruses from other animal species, namely certain species of civets, i.e. the masked palm civet (Paguma larvata) and the Asian palm civet (Paradoxurus hermaphroditus) and certain species of bats, i.e. the Stoliczka's trident bat (Aselliscus stoliczkanus) and the Chinese rufous horseshoe bat (Rhinolophus sinicus) (Li et al. 2020 b). 
  • Apart from pangolins, civets, bats, snakes and turtles, certain species of mink have been discussed as further potential intermediate species (Li et al. 2020 b). 
  • As of May 2020 the intermediate host species is still not known (Liu et al. 2020 b).
  • One common assumption is that pangolins are the intermediate host species (Cyranoski 2020, Lau et al. 2020Nadeem et al. 2020Xiao et al. 2020Zhang et al. 2020 a, Zhang et al. 2020 b). But it might also be that pangolins are just natural hosts of coronaviruses that are closeky related to SARS-CoV-2 (Liu et al. 2020 b).
  • "Results of comparative genomic analysis suggest that SARS-CoV-2 might have originated from the recombination of a Pangolin-CoV-like virus with a Bat-CoV-RaTG13-like virus. The Pangolin-CoV was detected in 17 of 25 Malayan pangolins analyzed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against Pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus that is highly related to SARS-CoV-2 in pangolins suggests that they have the potential to act as the intermediate host of SARS-CoV-2." (Xiao et al. 2020)
  • "The molecular and phylogenetic analyses showed that this pangolin coronavirus (pangolin-CoV-2020) is genetically related to the SARS-CoV-2 as well as a group of bat coronaviruses but do not support the SARS-CoV-2 emerged directly from the pangolin-CoV-2020. Our study suggests that pangolins are natural hosts of Betacoronaviruses." (Liu et al. 2020 b)
  • "However, whether pangolin species are good candidates for SARS-CoV-2 origin is still under debate. Considering the wide spread of SARSr-CoVs in natural reservoirs, such as bats, camels, and pangolins, our findings would be meaningful for finding novel intermediate SARS-CoV-2 hosts to block interspecies transmission." (Zhang et al. 2020 a). 
  • "Whereas the current evidence mainly points to the pangolin as the most likely intermediate host, it is possible for other animals to also serve as intermediate hosts for the following two reasons. First, coronaviruses are known to have multiple intermediate hosts. For example, SARS-CoV, of which the palm civet (Paguma larvata) is the most well-known intermediate host, is also reported to use a raccoon dog (Nyctereutes procyonoides) and a ferret badger (Melogale moschata) as intermediate hosts. Second, the 91% sequence identity between the Manis [pangolin] coronavirus and 2019-nCoV is high enough to confirm an evolutionary relation between the two viruses but not high enough to consider them as the same viral species. To put this into perspective, the viral sequence from intermediate hosts of SARS-CoV and MERS-CoV are 99.8 and 99.9% identical to their human versions, respectively. Therefore, even with the discovery of Manis coronavirus, further searching for other potential intermediate hosts should be continued." (Zhang et al. 2020 b)
  • "The discovery of multiple lineages of pangolin coronavirus and their similarity to SARS-CoV-2 suggests that pangolins should be considered as possible hosts in the emergence of novel coronaviruses and should be removed from wet markets to prevent zoonotic transmission. [...] These novel pangolin coronavirus genomes have 85.5% to 92.4% sequence similarity to SARS-CoV-2 [...]. [...] To date, pangolins are the only mammals other than bats documented to be infected by a SARS-CoV-2 related coronavirus. It is striking that two related lineages of CoVs are found in pangolins independently sampled in different Chinese provinces and that both are also related to SARSCoV-2. This suggests that these animals may be important hosts for these viruses, which is surprising as pangolins are solitary animals with relatively small population sizes, reflecting their endangered status11. Indeed, on current data it cannot be excluded that pangolins acquired their SARS-CoV-2 related viruses independently from bats or another animal host, so that their role in the emergence of human SARS-CoV-2 remains unproven. In this context it is notable that both lineages of pangolin coronaviruses were obtained from trafficked Malayan pangolins, likely originating from Southeast Asia, and there is a marked lack of knowledge of the viral diversity maintained by this animal in regions where it is indigenous. Undoubtedly, the extent of virus transmission in pangolin populations requires additional investigation. However, the repeated occurrence of infections with SARS-CoV-2 related coronaviruses in Guangxi and Guangdong provinces suggests that this animal may play an important role in the community ecology of coronaviruses. Coronaviruses, including those related to SARS-CoV-2, are clearly present in many wild mammals in Asia5–7,12. Although the epidemiology, pathogenicity, interspecies infectivity and transmissibility of coronaviruses in pangolins remains to be studied, the data presented here strongly suggests that handling these animals requires considerable caution, and that their sale in wet markets should be strictly prohibited. Further surveillance on pangolins in the natural environment in China and Southeast Asia are clearly needed to understand their role in the emergence of coronaviruses and the risk of future zoonotic transmission." (Lam et al. 2020
  • "Our study demonstrated that neither snake nor turtle was the intermediate hosts for SARS-CoV-2, which further reinforced the concept that the reptiles are resistant against infection of coronavirus. Our study suggested that Bovidae and Cricetidae should be included in the screening of intermediate hosts for SARS-CoV-2." (Luan et al. 2020)
  • "We have shown that, besides currently confirmed [species that can possibly be infected] by SARS-CoV-2, pangolin, cat, cow, buffalo, goat, sheep and pigeon ACE2s [receptors] might be utilized by SARS-CoV-2, indicating potential interspecies transmission of the virus from bats to these animals" (Qiu et al. 2020)
  • "Given that SARS-CoV infection originates from the contact between humans and civets in the markets, closing wet markets and killing civets therein could have effectively ended the SARS epidemic. By the same reasoning, pangolins should be removed from wet markets to prevent zoonotic transmission, in view of the discovery of multiple lineages of pangolin beta-CoVs closely related to SARS-CoV-2. However, whether and how SARS-CoV-2 is transmitted to humans through pangolins and other mammals remain to be clarified in future investigations." (Ye et al. 2020)
  • Another possibility is that SARS-CoV-2 was transmitted directly from bats to humans, for example via the consumption of bats as food or bat parts as "traditional Chinese medicine" (Shereen et al. 2020)

Has the new coronavirus been identified in any non-human animals from the Huanan market?

Has the new coronavirus been identified from "environmental samples" from Huanan market? Is it certain that this virus was at all present at Huanan market?
  • Yes, and yes (Nishiura et al. 2020).
  • "Thirty-three of the 585 environmental samples collected from the Wuhan's Huanan Seafood Wholesale Market were found to contain the nucleic acid of the novel coronavirus, according to the National Institute for Viral Disease Control and Prevention under the China CDC. [...] Experts of the institute took the samples on Jan. 1 and Jan. 12 on instruction of the Chinese CDC. Thirty-one of the 33 positive samples were collected from the western zone of the market, where booths of wildlife trading concentrated." ( 27 January 2020)

Which animals were sold at the Huanan market?
  • "poultry", "birds" (probably other than "poultry"), snakes, bats, "farm animals", marmots, frogs, hedgehogs, (Ji et al. 2020)
  • "non-aquatic animals such as birds and rabbits" (Lu et al. 2020) [... but apparently also sea animals]
  • "[...] no bats were sold or found at the Huanan seafood market [...]." (Lu et al. 2020)
The press has also reported the following animal species being sold at the Huanan market (also see Wikipedia):
  • Badgers
  • Bamboo rats
  • Bats
  • Beavers
  • Camels (likely meat)
  • Chickens
  • Civets
  • Crabs
  • Crocodiles (crocodile babies)
  • Dogs
  • Donkey (likely meat)
  • Fishes (including striped bass, ...)
  • Foxes
  • Marmots
  • Ostriches
  • Otters
  • Peacocks
  • Pheasants
  • Pangolins
  • Pigs
  • Porcupines
  • Rabbits 
  • Sheep
  • Shrimp
  • Spotted deer
  • Salamanders
  • Snakes (including Bungarus multicinctus)
  • Turtles
  • Wolf puppies
Many of these animals were likely sold dead, in the form of so-called bushmeat (wild animal meat).

Which species of snakes are common in the area around Wuhan?
"Two types of snakes are common in Southeastern China including the city of Wuhan" (Ji et al. 2020):
  • Bungarus multicinctus: "many-banded krait", Taiwanese krait, Chinese krait
... and ...

Are some scientists planning to conduct animal experiments to find out more about the new coronavirus?
  • "[...] requires further validation by experimental studies in animal models." (Ji et al. 2020)
  • "[.] the broad spectrum antiviral peptides against S2 would be an important preventive and treatment modality for testing in animal models before clinical trials [...]." (Chan et al. 2020)
  • "It would also be helpful to obtain more genetic and functional data about SARS-CoV-2, including animal studies." (Andersen et al. 2020)

Did the new coronavirus originally mostly spread from non-human animals to humans or from humans to humans?
  • From humans to humans. Already in December 2019 the virus seemed to have been spread mostly through human-to-human contact (Nishiura et al. 2020).

Where do coronaviruses generally come from?
  • Generally they come from bats - originally. They usually spread from bats to some other animal species, and from that animal species to humans. (Huang et al. 2020, Lu et al. 2020) (See the graphic below.)
  • The most famous coronaviruses so far were the SARS virus and the MERS virus - and they came from bats, indirectly: SARS via civet cats (masked palm civet, Paguma civet, Himalayan palm civet, Paguma larvata) and MERS via dromedaries (Arabian camels, Camelus dromedarius) (Chan et al. 2020, Cui et al. 2019, Huang et al. 2020). (See the graphic below.)

Note: This graphic is from early 2019, so it does not include the new coronavirus (SARS-CoV-2).
From Cui et al. 2019 "Origin and evolution of pathogenic coronaviruses":
"Fig. 2: Animal origins of human coronaviruses." 

"Severe acute respiratory syndrome coronavirus (SARS-CoV) is a new coronavirus that emerged through recombination of bat SARS-related coronaviruses (SARSr-CoVs). The recombined virus infected civets and humans and adapted to these hosts before causing the SARS epidemic. Middle East respiratory syndrome coronavirus (MERS-CoV) likely spilled over from bats to dromedary camels at least 30 years ago and since then has been prevalent in dromedary camels. HCoV-229E and HCoV-NL63 usually cause mild infections in immunocompetent humans. Progenitors of these viruses have recently been found in African bats, and the camelids are likely intermediate hosts of HCoV-229E. HCoV-OC43 and HKU1, both of which are also mostly harmless in humans, likely originated in rodents. Recently, swine acute diarrhoea syndrome (SADS) emerged in piglets. This disease is caused by a novel strain of Rhinolophus bat coronavirus HKU2, named SADS coronavirus (SADS-CoV); there is no evidence of infection in humans. Solid arrows indicate confirmed data. Broken arrows indicate potential interspecies transmission. Black arrows indicate infection in the intermediate animals, yellow arrows indicate a mild infection in humans, and red arrows indicate a severe infection in humans or animals." (Cui et al. 2019)

"The constant spillover of viruses from natural hosts to humans and other animals is largely due to human activities, including modern agricultural practices and urbanization. Therefore, the most effective way to prevent viral zoonosis is to maintain the barriers between natural reservoirs and human society [...]." (Cui et al. 2019)

Pictures from Huanan market in Wuhan:
Unknown date (Muyi Xiao)

After the new coronavirus outbreak had been discovered (probably from December 2019/January 2020) (Muyi Xiao)

Additional nerd info:

In which animal species do coronaviruses exist?
  • "Coronaviruses have been identified in several avian hosts [birds] as well as in various mammals, including camels, bats, masked palm civets, mice, dogs, and cats. Novel mammalian coronaviruses are now regularly identified. For example [a] coronavirus of bat origin was responsible for a fatal acute diarrhoea syndrome in pigs in 2018." (Lu et al. 2020

Where did SARS and MERS come from?
  • "[...] severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), a novel betacoronavirus that emerged in Guangdong, southern China, in November, 2002, and resulted in more than 8000 human infections and 774 deaths in 37 countries during 2002–03" (Lu et al. 2020)
  • "Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV), which was first detected in Saudi Arabia in 20127 and was responsible for 2494 laboratory-confirmed cases of infection and 858 fatalities since September, 2012, including 38 deaths following a single introduction into South Korea" (Lu et al. 2020)

What are coronaviruses?
  • "Coronaviruses (CoVs) are enveloped, positive-sense, single-stranded RNA viruses that belong to the subfamily Coronavirinae, family Coronavirdiae, order Nidovirales. There are four genera of CoVs, namely, Alphacoronavirus (αCoV), Betacoronavirus (βCoV), Deltacoronavirus (δCoV), and Gammacoronavirus (γCoV). Evolutionary analyses have shown that bats and rodents are the gene sources of most αCoVs and βCoVs, while avian species are the gene sources of most δCoVs and γCoVs. CoVs have repeatedly crossed species barriers and some have emerged as important human pathogens." (Chan et al. 2020)

Which animal species can coronaviruses infect?
  • “[Some] [c]oronavirus[es] can infect humans and many different animal species, including swine [pigs], cattle, horses, camels, cats, dogs, rodents, birds, bats, rabbits, ferrets, mink[s], snake[s], and other wildlife animals.” (Ji et al. 2020)

When was the new coronavirus (SARS-CoV-2) first reported?
  • "On 12 December 2019, Wuhan Municipal Health Commission (WMHC) reported 27 cases of viral pneumonia with 7 of them being critically ill." (Ji et al. 2020)

Info box: wildlife production in China

Wildlife (non-domesticated non-human animals) sold at markets are not just animals caught in the wild (in nature). They are also (maybe mostly) farmed wild animals.
In China the “Wildlife Protection Law (WPL)” permits the breeding of captive “wildlife” if the breeder has a permit.

“China has constructed a permit system of captive breeding of wildlife, a system of hunting prohibition and license of wildlife, a system of regulated transfer and trade of wildlife or wildlife products, and a system of regulated utilization of wildlife or wildlife products pertinent to the legal utilization of wildlife.
The captive breeding of wildlife under special state protection should meet certain conditions in order to obtain a captive breeding permit. The 2016 WPL, for the first time, stipulates some welfare measures for wildlife captive breeding. For instance, anyone intending to breed wildlife under special state protection shall ensure that: (1) They have the necessary living space and conditions for the movement, reproduction, hygiene, and health of the animal, according to its habits and properties; (2) they are equipped with adequate premises, facilities, and technology in line with the purpose, type, and scale of the captive breeding operation; (3) they can satisfy related technical standards and disease-prevention requirements; and (4) the wildlife is not abused.
The 2016 WPL stipulates that wildlife under special state protection, and the products thereof, are prohibited from production and trade for use as food; and the illegal purchase of such wildlife and the products for use as food are also prohibited. Moreover, a reinterpretation of Criminal Law by the Standing Committee of the National People’s Congress in 2014 added the stipulation that the consuming or eating of 420 rare or endangered species could constitute a crime and is liable to sentencing of over 10 years in prison, depending on the offense. For wildlife not under special state protection, or the products thereof, management and utilization need registration in the Market Regulation Department (previously the Industry and Commerce Administrative Department). The Departments of Wildlife Protection and Market Regulation, at all levels, are responsible for both supervising and inspecting the commercial utilization of wildlife and wildlife products. The current legislation in China on the utilization of wildlife has two limitations. On the one hand, the conditions required for captive breeding of wildlife are insufficient. The 2016 WPL, the Regulation on Terrestrial Wildlife Protection, the Management Rules of Domestication, and the Propagation License of National Key Protected Wildlife have strict conditions for receiving a permit to captive-breed wildlife. However, once receiving the permit, the laws, regulations, and rules are not clearly outlined regarding the management and supervision of captive animals. Although the 2016 WPL stipulates some welfare measures of wildlife’s captive breeding, it is difficult to assess the abuse of captive breeding wildlife in practice. One example is bear bile farming. Until 2009, there were more than 10 enterprises of bear bile farming, with more than 200 breeding bears, and a total bear stock of more than 10,000 [7]. The opponents argue that both permanent implantation and free drip cause bears a great amount of suffering [24,25]. The bear’s abdomen has an unhealed wound used to extract bile. It is an abusive behavior, violating the regulation of the 2016 WPL. The supporters think that, as approved by the 2016 WPL, wildlife and the products thereof, under special state protection for which there exist established knowledge and techniques for captive breeding, like bear bile farming with a special marking, can be sold and utilized, if the captive breeding of bears complies with the regulations concerning the animals’ welfare, such requirements specified for basic conditions of the facilities, living space, breeding technology, etc. Whether supporting or opposing the bear bile farming, parties on both sides can find within the 2016 WPL an argument for their own opinion, which indicates the conflicts and inconsistencies within the law. The stipulations on consumption of wildlife, and the products thereof, are not comprehensive. Much of the world’s massive illegal wildlife trade—such as poached tigers, pangolins, bears, etc.—occurs in China [26]. According to a survey conducted in various trading places in Southwest China, around 50% of the respondents agreed upon wildlife protection, while 60% had consumed wildlife in the last two years [27]. An attitudinal survey on wildlife consumption and protection awareness distributed in Beijing, Shanghai, Guangzhou, Kunming, and Nanning in China showed that the proportion of respondents who had consumed wildlife had decreased slightly from 31.3% in 2008 to 29.6% in 2014 [28]. The consumption of wildlife, and the products thereof, has greatly stimulated the hunting and trade of wildlife. It is unquestionable that trading in rare or endangered species is illegal in China. While the 2016 WPL emphasizes prohibition of wildlife consumption under state protection, the legal interpretation of the Criminal Law and the 2016 WPL still allows consumers to eat wildlife and wildlife products that are not under state protection. Regarding the imperfect stipulation on wildlife utilization, making detailed stipulations on the management and supervision of wildlife’s captive breeding to avoid illegal hunting is urgent. The utilization activities that have obvious negative impacts on animal welfare—e.g., bear bile farming—should be gradually abolished. Further, the stipulation of treating animals as an exploitable natural resource should be abolished in the long term as an ethical perspective [29]. As stated in the report of the 19th National Congress of the Communist Party of China, human and nature are the community of destiny, and humans must respect, adapt to, and protect nature [30].” (Feng et al. 2019)

"In China, there are several tens of thousands of farms, where hundreds of species are raised, including snakes, civets, bears, deer, turtles, bamboo rats, porcupines, foxes, mink and birds." (Zhai et al. 2020)

"There must be a complete ban on utilizing wild animals and birds as a source of food." (Shereen et al. 2020)

"After reports on the zoonotic origins of SARS-CoV surfaced (Peiris et al., 2004; Stadler et al., 2003), Chinese authorities ordered the slaughter of over 10 000 animals due to be sold in live animal markets, including civets, raccoon dogs, and ferret badgers, and the USA instituted a trade embargo on civet cats ( After dromedary camels were implicated in the spread of MERS-CoV, the Office International des Epizooties (OIE) announced that positive real-time PCR results for MERS-CoV or isolation of the pathogen from dromedary camels is an OIE-notifiable event to mitigate the health risk of the virus to humans, and to prevent international spread. Cooking of camel meat and pasteurization of camel milk before consumption was promoted (Hemida et al., 2017). After the discovery that pangolins harbour HCoV-19 [SARS-CoV-2] related coronaviruses, Chinese authorities put a ban on the trade and sales for wild animals. At present, we are still uncertain of the final consequence of HCoV-19 on wild animal management, and how this will shape our future life and animal conservation and usage." (Wong et al. 2020)

"The newly identified coronavirus in the most-trafficked mammal [pangolins] could represent a future threat to public health if wildlife trade is not effectively controlled." (Xiao et al. 2020)

"Large surveillance of coronaviruses in pangolins could improve our understanding of the spectrum of coronaviruses in pangolins. In addition to conservation of wildlife, minimizing the exposures of humans to wildlife will be important to reduce the spillover risks of coronaviruses from wild animals to humans." (Liu et al. 2020 b)

"The rapid urbanization and shift to a market economy in these countries [China, Myanmar, Vietnam, Thailand], and the subsequent emergence of hundreds of millions of potential middle-class consumers wanting to emulate elitist foodways, has boosted the demand for wild meat, trade of wild animals, attendance of wet markets, and food and medicinal consumption of wild animals.
These animals are sourced legally or illegally, from the wild or from wildlife farms. A source for these species is the thousands of wildlife farms that have arisen in China during the last twenty years, which can be seen as attempts to intensify “wildlife production.” These farms raise a number of animals for food, from peacocks to porcupines and civets, which are often believed to have powerful medicinal and magical/symbolic properties." (Volpato et al. 2020)

Could SARS-CoV-2 spread to factory farms?
"How prevalent is the virus in its natural host, and does it possess the ability to infect other animals? This question is relevant because [previous] coronavirus[es] originating in the bat has been found to cross the species barrier and infect pigs [9], which are hypothesized to serve as the 'mixing vessels' for the generation of genetically novel viruses. The introduction of 2019-nCoV into livestock animals could pose a potential threat to both agriculture and public health." (Xu 2020)

Can SARS-CoV-2 infect pets (companion animals)?
Yes, it could. Cats can be infected by breathing in airborne droplets (Shi et al. 2020).

More pictures:

What should be done to prevent future outbreaks? Why not think big … and maybe consider the ethical treatment of animals too?
  • Make (all) wildlife breeding and wildlife markets (worldwide) illegal.
  • Abolish factory farming. (Field 2009)
Suggestions by Yang et al. 2020: 
“Fig. 9. Keys to the control of future hCoV [coronaviruses that can infect humans] epidemics. Lessons learned from both the SARS and SARS-CoV-2 epidemics.” (Yang et al. 2020

Note: The development of vaccines unfortunately involves animal experiments.
Note: What is not mentioned here is that it’s always a good idea to keep your immune system strong – as far as we can have an influence on that.

This post isn’t about how COVID-19 is or should be treated. But this graphic seems quite nice:

"Fig. 8. The treatment and management of COVID-19 pneumonia. ICU: intensive care unit; ECMO: extracorporeal membrane oxygenation." (Yang et al. 2020

Note: I would be very sceptical about using or recommending Chinese Traditional Medicine. Superstitious beliefs about alleged “medicinal” products made from animals are likely part of the cause for this outbreak (Wassenaar and Zou 2020).

Info box: use of bats in Traditional Chinese Medicine

"[...] bats are used in Traditional Chinese Medicine, and their handling poses a potential risk to cause zoonotic coronavirus epidemics.
bats are the likely natural host of 2019_nCoV, the exact bat species that serves as the natural host of the virus remains as yet unknown. Chinese bat species with commercial value were identified as natural reservoirs of coronaviruses and are used in Traditional Chinese Medicine. Since their trading provides a potential risk for spreading zoonoses, a change in these practices is highly recommended.
[...] bats and their excrements are often used in Traditional Chinese Medicine (TCM), which may be a reason for their legal or illegal trading. [...] Of an extensive list of bat species that historically have been used in TCM (Riccucci 2012), five were found to carry coronaviruses, as reported in a surveillance study (Tang et al. 2006): Pipistrellus abramus, Murina leucogaster, Rhinolophus ferrumequinum, Scotophilus kuhlii and Scotomanes ornatus. Of these bat species, the first three can be found in the province of Hubei (source:; the habitat of S. ornatus reaches to the south of the province but does not cover the Wuhan area, while S. kuhlii is not endemic in this region.
Highly similar coronaviruses can be detected in different bat species (as identified by asterisks in Fig. 2), so that even a high similarity match to a bat isolate may not always identify the correct bat species that was the cause of a given zoonotic outbreak. This caution can be extended to other possible animal hosts that have been or will be claimed as sources of the 2019_nCoV without a proven epidemiological link.
The use of bats in TCM is of great concern, and the use of the Greater horseshoe bat, Rhinolophus ferrumequinum, is of particular interest. The faeces of this bat (Yè ming shǎ [夜明砂] in Chinese, marketed as Vespertilionis, see for instance is used to cure eye conditions, while body parts are dried and added to wine or ground into a powder for oral intake as a means to ‘detoxify’ the body. Both practices could be highly risky in case an animal was infected with a coronavirus, particularly the first use, as the virus can be present in faeces [?] and can enter a host via the eye. We speculate that a live or recently deceased infected bat species was handled by traders because of its value in TCM, and that such an infected individual, or the still infective bat or bat products, may have been the route by which the virus entered the exotic meat market in Wuhan. Alternatively, during the trade chain, a host jump occurred between an infected bat (handled for TCM purposes) and another mammal, that then was the source of infection. Less likely, because the material is usually dried significantly, the outbreak may have started by medicinal use of bat‐derived, contaminated TCM material. In this respect it is interesting to note that the first known onset of symptoms (on 1 December 2019) were observed in a patient with no known epidemiological links to the Wuhan food market (Huang et al. 2020).
The possibility that bat‐derived materials sold for TCM practices may be involved in this outbreak, has severe implications. We point out there is a serious risk of producing bat‐derived materials sold for TCM practices as it involves handling of and trading with wild bats. Even when the selling of live wild animals at food markets would be completely prohibited in China, the trading and handling of bats for traditional medicinal practices would remain a serious risk for future zoonotic coronavirus epidemics." (Wassenaar and Zou 2020)

Info box: pangolins used as food in China

[Note: Pangolins are also used as food and for "medicinal" purposes in several other countries. See: Volpato et al. 2020]

"The available literature suggest that there are two main drivers that enhance the necessary conditions for infectious diseases to cross the species barrier from wild animals to humans: (1) the encroachment of human activities (e.g., logging, mining, agricultural expansion) into wild areas and forests and consequent ecological disruptions; and [...] (2) the commodification of wild animals (and natural resources in general) and an expanding demand and market for wild meat and live wild animals, particularly in tropical and sub-tropical areas. In particular, a crucial role may have been played by the bushmeat-euphoria and attached elitist gastronomies and conspicuous consumption phenomena.
In China, pangolins are highly sought after for traditional medicine (Fig. 1 [see below]) and as food [72]. This demand causes over-exploitation that, coupled with habitat loss, threatens the very survival of the species used. Pangolin scales are regarded as a medicinal panacea (like rhino horns, and like rhino horns they are made of keratin), and their meat is considered a delicacy. The demand for pangolins in China is met by an illegal trade that is lucrative and on the rise, lately attracting wildlife traffickers who used elephant ivory as their prime generator of profits. The demand for pangolin meat and scales, due to increasing conspicuous consumption by the Asian middle class, has driven pangolins to the verge of extinction [73]. From all forested corners of the tropics, pangolins are transported to Asian markets, where stressed and likely immune depressed pangolins are caged with many other species, and also with their own pathogens. This has emptied forests of pangolins: a steady decrease of pangolins, and wildlife in general, in African forests has been reported by local hunters and traditional healers in studies in Southwestern Nigeria [67] and in Cameroon [74].
The pangolin is prized as a delicacy in China, especially in the Southern and Eastern part of the country [75]. According to Challender et al. [76], this culinary practice is attested to by historical sources dating back to the 12th century CE: in present-day Jiangxi Province, Chinese pangolin meat was common street food during wintertime, cooked in lees from fermented rice wine. A popular recipe from the mountain village of Zhu Yu, dating back to the 16th century CE, consisted of curing pangolin meat in salt for two days before boiling it in water [77]. Nowadays, pangolin is served in high-end restaurants in urban cities, mostly in Anuhi, Fujian, Jiangxi, Guangxi, Yunnan, Guizhou, Guangzhou, Guangdong, and Guangxi provinces.
[75, 76, 7880]. Once the order is placed, the animal may be hammered until it is unconscious and then slaughtered in front of the customers as a guarantee of the meat’s freshness. Some other time instead the animal is smuggled to the restaurant already dead and preserved in ice. Blood is drained and usually given to the customer to bring home. The dead animal is placed in hot water to remove the scales and the meat is cut into small pieces [81], which then may be boiled, stewed, braised, or steamed.
Chopped pangolin meat is usually stewed with Chinese wine, other meat including chicken or pork, and medicinal herbs such as Ligusticum striatum, Tetrapanax papyrifer, Stemmacantha, and Akebia spp. [82].
In Shenzhen (Guangdong Province), pangolin meat is served in hot pot [81]. Pangolin meat is also an ingredient of “eight animal stew”, a dish made from animals like pangolin, swan, and snake simmered together for five hours, and a soup prepared with pangolin meat and caterpillar fungus (Ophiocordyceps sinensis) [83] (Fig. 2 [see below]).
Several recipes including pangolin meat are prepared in Fujan gastronomy. In the western mountainous area, pangolin meat is steamed, simmered, and served/covered with a gelatinized sauce made with onion, soy sauce, ginger, Shaoxing wine, chicken soup, and Danggui (Angelica sinensis roots) [79]. A soup is also prepared by boiling the meat, which is served with pieces of pangolin tongue [84]. In the villages of the Yunnan–Guizhou Plateau (Yunnan and Guizhou provinces), a pangolin and chestnut stew is part of the local cuisine [80]. Besides meat, pangolin fetuses are eaten in soup (Fig. 3 [see below]).
Moreover, baby pangolins are boiled in rice wine to brew a tonic and the blood is used as an ingredient in pangolin-blood fried rice (Fig. 4 [see below] [85].
In the wake of the COVID-19 pandemic, the Chinese government has shut down wet markets all over the country and has begun a campaign of awareness concerning the importance of protecting wild species for collective health. The banning of wet markets, wildlife trade, and wildlife farming, without driving down the demand for wild meat, risks causing the trade to move underground, with a potentially even worse impact on commercialized species. Rather, demand can be reduced by informing and educating consumers about the consequences of their food desires and habits; there is no prestige in driving species to extinction.
At the same time, there is the need to support alternative livelihoods for hunters, traders, and wildlife farmers if and when banning wet markets and wildlife trade. In the absence of alternative means of subsistence, any ban on wildlife trade and consumption will have a disproportionate effect on their livelihoods, pushing many of them into poverty and illegality [95].
The sanctioning of wildlife farming by the Chinese Government has probably improved the livelihoods and economic conditions of wildlife farmers, many of whom have been pushed out of the livestock sector and into wildlife farming at the forest’s [.]edge during the 1990s 
by the expansion of intensive livestock husbandry [factory farming][97], but may have contributed in opening up an old Pandora’s Box [emerging new zoonoses]."
(Volpato et al. 2020)

Deserted public spaces in China (unthinkable in Europe - at the time of first creating this post):

"Fig. 10. Life in China in Beijing and Hubei during quarantine measures. Quarantine measures have led to empty streets and shopping centers." (Yang et al. 2020)

This post isn't about how to protect yourself and others but ...
"[...] hand shaking is not part of Chinese culture, but it is almost automatic in other parts of the world, and it is normally done without even thinking. This is the first thing that would have to stop to help contain the virus." (Yang et al. 2020)

Can it happen again?

"Given that the cross-species transmission of SARS-CoV-2 is currently not well understood, and no effective approach to stop such zoonotic transmission has been established, SARS-related coronaviruses, such as SARS-CoV-2 (or even SARS-CoV-3 in the future), might continue to emerge and re-emerge." (Wu et al. 2020)

Last words: And always remember ... don't be a racist.
"Unfortunately, emergence of SARS-CoV-2 has led to numerous reports of Asians being subjected to racist behavior and hate crimes across the world." (Yang et al. 2020)

And another word of caution: 
"[...] epidemics provide a sampling device for social analysis. They reveal what really matters to a population and whom they truly value.
One dramatic aspect of epidemic response is the desire to assign responsibility. From Jews in medieval Europe to meat mongers in Chinese markets, someone is always blamed. This discourse of blame exploits existing social divisions of religion, race, ethnicity, class, or gender identity.
Two familiar aspects of the response to epidemics are especially disheartening. First, stigmatization follows closely on the heels of every pathogen. Anti-Chinese hostility has been a recurrent problem, whether with plague in San Francisco in 1900, SARS in 2003, or Covid-19 today. 
Are we now in one of those rare moments, facing a pathogen with just the right (wrong?) mix of contagiousness and virulence, with societies providing the requisite human–animal contact, urban crowding, global travel, and populations stressed by growing social inequality? Given the historical rarity of catastrophic epidemics, such a perfect storm must be unlikely. But it is, regrettably, a possibility. [...]" (Jones 2020)