Severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1), previously known as severe acute respiratory syndrome coronavirus (SARS-CoV),
is a
strain of
coronavirus
Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the comm ...
that causes severe acute respiratory syndrome (
SARS
Severe acute respiratory syndrome (SARS) is a viral respiratory disease of zoonotic origin caused by the virus SARS-CoV-1, the first identified strain of the SARS-related coronavirus. The first known cases occurred in November 2002, and the ...
), the
respiratory illness responsible for the
2002–2004 SARS outbreak
The 2002–2004 outbreak of SARS, caused by severe acute respiratory syndrome coronavirus (SARS-CoV or SARS-CoV-1), infected over 8,000 people from 30 countries and territories, and resulted in at least 774 deaths worldwide.
The outbreak w ...
.
It is an
enveloped,
positive-sense,
single-stranded RNA virus
An RNA virus is a virus characterized by a ribonucleic acid (RNA) based genome. The genome can be single-stranded RNA (ssRNA) or double-stranded (Double-stranded RNA, dsRNA). Notable human diseases caused by RNA viruses include influenza, SARS, ...
that infects the
epithelial cells
Epithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial ( mesothelial) tissues line the outer surfaces of man ...
within the lungs. The virus enters the host cell by binding to
angiotensin-converting enzyme 2
Angiotensin-converting enzyme 2 (ACE2) is an enzyme that can be found either attached to the membrane of cells (mACE2) in the intestines, kidney, testis, gallbladder, and heart or in a soluble form (sACE2). Both membrane bound and soluble ACE2 ...
.
It infects
humans
Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...
,
bats
Bats are flying mammals of the order Chiroptera (). With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most birds, flying with their very long spread-out ...
, and
palm civets. The SARS-CoV-1 outbreak was largely brought under control by simple public health measures. Testing people with symptoms (fever and respiratory problems), isolating and quarantining suspected cases, and restricting travel all had an effect. SARS-CoV-1 was most transmissible when patients were sick, so its spread could be effectively suppressed by isolating patients with symptoms.
On April 16, 2003, following
the outbreak of SARS in
Asia
Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...
and secondary cases elsewhere in the world, the
World Health Organization
The World Health Organization (WHO) is a list of specialized agencies of the United Nations, specialized agency of the United Nations which coordinates responses to international public health issues and emergencies. It is headquartered in Gen ...
(WHO) issued a press release stating that the
coronavirus
Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the comm ...
identified by a number of laboratories was the official cause of SARS. The
Centers for Disease Control and Prevention
The Centers for Disease Control and Prevention (CDC) is the National public health institutes, national public health agency of the United States. It is a Federal agencies of the United States, United States federal agency under the United S ...
(CDC) in the United States and the
National Microbiology Laboratory
The National Microbiology Laboratory (NML) is part of the Public Health Agency of Canada (PHAC), the agency of the Government of Canada that is responsible for public health, health emergency preparedness and response, and infectious and chronic ...
(NML) in Canada identified the SARS-CoV-1
genome
A genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as ...
in April 2003. Scientists at
Erasmus University
Erasmus University Rotterdam ( ; abbreviated as EUR) is a public university, public research university located in Rotterdam, Netherlands. The university is named after Desiderius Erasmus, Desiderius Erasmus Roterodamus, a 15th-century Christia ...
in
Rotterdam
Rotterdam ( , ; ; ) is the second-largest List of cities in the Netherlands by province, city in the Netherlands after the national capital of Amsterdam. It is in the Provinces of the Netherlands, province of South Holland, part of the North S ...
, the Netherlands, demonstrated that the SARS coronavirus fulfilled
Koch's postulates
Koch's postulates ( ) are four criteria designed to establish a causality, causal relationship between a microbe and a disease. The postulates were formulated by Robert Koch and Friedrich Loeffler in 1884, based on earlier concepts described by ...
, thereby confirming it as the causative agent. In the experiments,
macaque
The macaques () constitute a genus (''Macaca'') of gregarious Old World monkeys of the subfamily Cercopithecinae. The 23 species of macaques inhabit ranges throughout Asia, North Africa, and Europe (in Gibraltar). Macaques are principally f ...
s infected with the virus developed the same symptoms as human SARS patients.
A virus very similar to SARS was discovered in late 2019. This virus, named
severe acute respiratory syndrome coronavirus 2
Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) is a strain of coronavirus that causes COVID-19, the respiratory illness responsible for the COVID-19 pandemic. The virus previously had the Novel coronavirus, provisional nam ...
(SARS-CoV-2), is the causative
pathogen
In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a Germ theory of d ...
of
COVID-19
Coronavirus disease 2019 (COVID-19) is a contagious disease caused by the coronavirus SARS-CoV-2. In January 2020, the disease spread worldwide, resulting in the COVID-19 pandemic.
The symptoms of COVID‑19 can vary but often include fever ...
, the propagation of which started the
COVID-19 pandemic
The COVID-19 pandemic (also known as the coronavirus pandemic and COVID pandemic), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began with an disease outbreak, outbreak of COVID-19 in Wuhan, China, in December ...
. The
spike protein
In virology, a spike protein or peplomer protein is a protein that forms a large structure known as a spike or peplomer projecting from the surface of an viral envelope, enveloped virus. as cited in The proteins are usually glycoproteins that ...
responsible for viral entry differs by 24% between the two viruses, and the genome differs by approximately 20%, indicating that the two do not share a very recent common ancestor.
SARS
Severe acute respiratory syndrome
Severe acute respiratory syndrome (SARS) is a viral respiratory disease of zoonotic origin caused by the virus SARS-CoV-1, the first identified strain of the SARS-related coronavirus. The first known cases occurred in November 2002, and the sy ...
(SARS) is the disease caused by SARS-CoV-1. It causes an often severe illness and is marked initially by systemic symptoms of
muscle pain
Myalgia or muscle pain is a painful sensation evolving from muscle tissue. It is a symptom of many diseases. The most common cause of acute myalgia is the overuse of a muscle or group of muscles; another likely cause is viral infection, espec ...
,
headache
A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...
, and
fever
Fever or pyrexia in humans is a symptom of an anti-infection defense mechanism that appears with Human body temperature, body temperature exceeding the normal range caused by an increase in the body's temperature Human body temperature#Fever, s ...
, followed in 2–14 days by the onset of respiratory symptoms,
mainly cough,
dyspnea
Shortness of breath (SOB), known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing discomfort that ...
, and
pneumonia
Pneumonia is an Inflammation, inflammatory condition of the lung primarily affecting the small air sacs known as Pulmonary alveolus, alveoli. Symptoms typically include some combination of Cough#Classification, productive or dry cough, ches ...
. Another common finding in SARS patients is a decrease in the number of lymphocytes circulating in the blood.
In the SARS outbreak of 2003, about 9% of patients with confirmed SARS-CoV-1 infection died.
The mortality rate was much higher for those over 60 years old, with mortality rates approaching 50% for this subset of patients.
This outbreak led to many research programs, such as
Predict and the Understanding the Risk of Bat Coronavirus Emergence grant, which aimed to identify zoonotic risks prior to spillover in humans, but ultimately failed to prevent the
SARS-CoV-2 pandemic.
Origin and evolutionary history

In March 2003, WHO established a global network of leading laboratories to collaborate in the identification of the causative agent of SARS. Early on, labs in the network narrowed the search to members of the
paramyxovirus and coronavirus families. Early findings shared by the labs pointed to coronaviruses with increasing consistency. On 21 March, scientists from the
University of Hong Kong
The University of Hong Kong (HKU) is a public research university in Pokfulam, Hong Kong. It was founded in 1887 as the Hong Kong College of Medicine for Chinese by the London Missionary Society and formally established as the University of ...
announced the isolation of a new virus that was strongly suspected to be the causative agent of SARS.
Epidemiological evidence suggested a
zoonotic
A zoonosis (; plural zoonoses) or zoonotic disease is an infectious disease of humans caused by a pathogen (an infectious agent, such as a virus, bacterium, parasite, fungi, or prion) that can jump from a non-human vertebrate to a human. When h ...
origin of the virus: more than 33% of the first detected cases of SARS in Guangdong corresponded to animal or food handlers.
Seroprevalence studies reinforced this zoonotic link (a high proportion of asymptomatic animal handlers at markets in Guangdong Province had antibodies against SARS-CoV).
On April 12, 2003, scientists working at the Michael Smith Genome Sciences Centre in
Vancouver
Vancouver is a major city in Western Canada, located in the Lower Mainland region of British Columbia. As the List of cities in British Columbia, most populous city in the province, the 2021 Canadian census recorded 662,248 people in the cit ...
finished mapping the
genetic sequence
Genetic may refer to:
*Genetics, in biology, the science of genes, heredity, and the variation of organisms
**Genetic, used as an adjective, refers to genes
*** Genetic disorder, any disorder caused by a genetic mutation, whether inherited or de no ...
of a coronavirus believed to be linked to SARS. The team was led by
Marco Marra
Marco Antonio Marra is a distinguished scientist and director of Canada's Michael Smith Genome Sciences Centre at the BC Cancer Research Centre and professor of medical genetics at the University of British Columbia (UBC). He also serves as UB ...
and
Caroline Astell and worked in collaboration with the
British Columbia
British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...
Centre for Disease Control and the
National Microbiology Laboratory
The National Microbiology Laboratory (NML) is part of the Public Health Agency of Canada (PHAC), the agency of the Government of Canada that is responsible for public health, health emergency preparedness and response, and infectious and chronic ...
in
Winnipeg
Winnipeg () is the capital and largest city of the Provinces and territories of Canada, Canadian province of Manitoba. It is centred on the confluence of the Red River of the North, Red and Assiniboine River, Assiniboine rivers. , Winnipeg h ...
,
Manitoba
Manitoba is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population ...
, using samples from infected patients in
Toronto
Toronto ( , locally pronounced or ) is the List of the largest municipalities in Canada by population, most populous city in Canada. It is the capital city of the Provinces and territories of Canada, Canadian province of Ontario. With a p ...
.
The map is shared with scientists worldwide via the GSC website.
Donald Low of
Mount Sinai Hospital in Toronto described the discovery as having been made with "unprecedented speed". The sequence of the SARS coronavirus has since been confirmed by other independent groups.
Molecular epidemiological research demonstrated the virus isolated in 2002–2003 in south China and the virus isolated in the same area in late 2003 and early 2004 are different, indicating separate species-crossing events.
The phylogeny of the outbreak strains shows that the southwestern provinces including Yunnan, Guizhou and Guangxi compare to the human SARS-CoV-1 better than those of the other provinces, but the viruses' evolution is a product of the host interaction and particularity.
In late May 2003, studies from samples of wild animals sold as food in the local market in
Guangdong
) means "wide" or "vast", and has been associated with the region since the creation of Guang Prefecture in AD 226. The name "''Guang''" ultimately came from Guangxin ( zh, labels=no, first=t, t= , s=广信), an outpost established in Han dynasty ...
, China, found a strain of SARS coronavirus could be isolated from
masked palm civet
The masked palm civet (''Paguma larvata''), also called the gem-faced civet or Himalayan palm civet, is a viverrid species native to the Indian subcontinent and Southeast Asia. It has been listed as least concern on the IUCN Red List since 2008 ...
s (''Paguma'' sp.), but the animals did not always show clinical signs. The preliminary conclusion was the SARS virus crossed the
species barrier from palm civet to humans, and more than 10,000 masked palm civets were killed in Guangdong Province. The virus was also later found in
raccoon dog
''Nyctereutes'' (Greek: ''nyx, nykt-'' "night" + ''ereutēs'' "wanderer") is a genus of canid which includes only two extant species, both known as raccoon dogs: the common raccoon dog (''Nyctereutes procyonoides'') and the Japanese raccoon do ...
s (''Nyctereuteus'' sp.),
ferret badgers (''Melogale'' spp.), and domestic cats.
In 2004, scientists from the
Chinese Center for Disease Control and Prevention
The Chinese Center for Disease Control and Prevention (CCDC; ) is an institution directly under the National Health Commission, based in Changping District, Beijing, China.
Established in 1983, it works to protect public health and safety ...
of the
University of Hong Kong
The University of Hong Kong (HKU) is a public research university in Pokfulam, Hong Kong. It was founded in 1887 as the Hong Kong College of Medicine for Chinese by the London Missionary Society and formally established as the University of ...
and the
Guangzhou
Guangzhou, Chinese postal romanization, previously romanized as Canton or Kwangchow, is the Capital city, capital and largest city of Guangdong Provinces of China, province in South China, southern China. Located on the Pearl River about nor ...
Center for Disease Control and Prevention established a genetic link between the SARS coronavirus appearing in civets and humans, confirming claims that the virus might have transmitted from the animal species to humans. Infected palm civets at the market were traced to farms where no infected animals were found. It is unknown whether the virus was originally introduced to the market by civets, humans, or another animal.
In 2005, two studies identified a number of SARS-like coronaviruses in Chinese
bat
Bats are flying mammals of the order Chiroptera (). With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most birds, flying with their very long spread-out ...
s.
Although the bat SARS virus did not replicate in cell culture, in 2008, American researchers altered the genetic structure of bat SARS virus with the human
receptor binding domain both in the bat virus and in the mice which demonstrated how
zoonosis
A zoonosis (; plural zoonoses) or zoonotic disease is an infectious disease of humans caused by a pathogen (an infectious agent, such as a virus, bacterium, parasite, fungi, or prion) that can jump from a non-human vertebrate to a human. When ...
might occur in evolution.
Phylogenetic analysis of these viruses indicated a high probability that SARS coronavirus originated in bats and spread to humans either directly or through animals held in Chinese markets. The bats did not show any visible signs of disease, but are the likely natural reservoirs of SARS-like coronaviruses.
Phylogenetic
Bats are likely to be the natural reservoir, that is, the host that harbored the pathogen but that does not show ill effects and serves as a source of infection. No direct progenitor of SARS-CoV was found in bat populations, but WIV16 was found in a cave in
Xiyang Yi Ethnic Township, Yunnan, China between 2013 and 2016, and has a 96% genetically similar virus strain. The hypothesis that SARS-CoV-1 emerged through recombinations of bat SARSr-CoVs in the Yunnan cave of WIV16 or in other yet-to-be-identified bat caves is considered highly likely.
Virology
SARS-CoV-1 follows the replication strategy typical of the
coronavirus
Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the comm ...
subfamily. The primary human receptor of the virus is
angiotensin-converting enzyme 2
Angiotensin-converting enzyme 2 (ACE2) is an enzyme that can be found either attached to the membrane of cells (mACE2) in the intestines, kidney, testis, gallbladder, and heart or in a soluble form (sACE2). Both membrane bound and soluble ACE2 ...
(ACE2) and hemaglutinin (HE), first identified in 2003, and the viral spike protein lacks a furin cleavage site.
Human SARS-CoV-1 appears to have had a complex history of
recombination between ancestral
coronavirus
Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the comm ...
es that were hosted in several different animal groups.
[Zhang XW, Yap YL, Danchin A. Testing the hypothesis of a recombinant origin of the SARS-associated coronavirus. Arch Virol. 2005 Jan;150(1):1–20. Epub 2004 Oct 11. ] In order for recombination to happen at least two SARS-CoV-1
genome
A genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as ...
s must be present in the same host cell. Recombination may occur during genome replication when the
RNA polymerase
In molecular biology, RNA polymerase (abbreviated RNAP or RNApol), or more specifically DNA-directed/dependent RNA polymerase (DdRP), is an enzyme that catalyzes the chemical reactions that synthesize RNA from a DNA template.
Using the e ...
switches from one template to another (copy choice recombination).
[
SARS-CoV-1 is one of seven known coronaviruses to infect humans. The other six are:]
* Human coronavirus 229E (HCoV-229E)
* Human coronavirus NL63 (HCoV-NL63)
* Human coronavirus OC43 (HCoV-OC43)
* Human coronavirus HKU1 (HCoV-HKU1)
* Middle East respiratory syndrome–related coronavirus (MERS-CoV)
* Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
Notably, SARS-CoV-1 is the second of three coronaviruses known to infect humans and use ACE2 (the others being HCoV-NL63 and SARS-CoV-2).
See also
* Carlo Urbani
Carlo Urbani (; 19 October 1956 – 29 March 2003) was an Italian physician and microbiologist and the first to identify severe acute respiratory syndrome (SARS) as probably a new and dangerously contagious viral disease, and his early warn ...
* SL-CoV-WIV1
References
Citations
Sources
*
*
*
*
*
*
*
External links
WHO press release identifying and naming the SARS virus
The SARS virus genetic map
''Science'' special on the SARS virus
(free content: no registration required)
*
U.S. Centers for Disease Control and Prevention (CDC) SARS home
World Health Organization on alert
{{DEFAULTSORT:Severe acute respiratory syndrome coronavirus
Animal viruses
Human viruses
Species described in 2003
Viruses described in the 21st century
SARS-related coronavirus
Infraspecific virus taxa
Chiroptera-borne diseases
Severe acute respiratory syndrome