Friday, April 24, 2020

ORGANIC AND NATURAL


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ORGANIC CASHEWS

40 grams of organic cashew nuts contain approximately 98% of copper, 34 % of phosphorus, 33% of manganese, 29 % of magnesium, carbohydrates, vitamins and other minerals. Without a doubt, organic cashews nuts are versatile and healthy and unique food as compared to other nuts with its nutrition value. Buy fresh cashew nuts online from panruti. Which is roasted and hand processed with good quality. You can be enjoyed with great enjoyment of these cashews, which is from panruti.
WHAT IS CASHEWNUTS:
     Cashews are thought of as ‘King of Nuts’ and also the king is usually in demand. Same is that the case with cashews, they’re liked by virtually everybody whether or not its children, teens or adults. children adore it for its sweet and buttery style, whereas teens relish it roast with drinks and snacks and adults being the smart ones within the family like it for its nutrition worth. So now, you see what causes this high demand. If we tend to take into account the reports the demand for cashews has exaggerated by 6th,June,1944 from the previous year ,whereas the provision has solely exaggerated by third-dimensional. This distinction within the demand and provide magnitude relation has affected the value of cashews in the native and wholesale markets. Then it can be used as a flavor to variety of food, which makes the food more delicious. It can be loved by all
WHY WE LOVE CASHEWS:
Who doesn’t apprehend and love cashews? we have a tendency to decision cashews ‘Kaju’ in Republic of India. they’re largely utilized in sweets which is distributed throughout festivals and loved by kids. Cashews is found in your native markets all year spherical and have perpetually been a special addition to food recipes. Cashews originally belong to Brazil and were brought by the Portuguese to Republic of India. These reniform balmy have ample health advantages and are thought of royal. Organic raw cashews are larger in size and these raw cashews are processed into cashew balmy. Organic cashew is full-grown in an exceedingly natural manner while not the employment of pesticides, herbicides, pesticides that degrade the standard and style of the nut. Organic cashew advantages a lot of as compared to traditional one.
BENEFITS OF ORGANIC CASHEWS:
     According to magnesium present in cashews it can help us to maintain blood pressure and keep away the blood diseases. Deficiency like iron deficiency will be prevented by cashews. It is energetic and has high density. Which will be extremely great for body builders, professional sports person, etc. It has more number of calcium. Cashew helps to maintain good cardiovascular health and provide protein to the body .
Cashews help us to strengthening immune system and the healing of wounds. Which is eaten anytime because they are rich in nutrients. It provides energy to maintain our body weight. It act as antioxidant against deficiencies because it has  minerals,vitamins,iron,phosphorous,etc.Cashew helps us to maintain good health when it is consumed in small quantity. Cashews mostly used in sweets which is sweeter and more loved by everyone. Cashew oil which makes our hair shiny and stronger. Then it can be used to skin glowing. Whenever we use cashew oil it will glow our skin.
BENEFITS FOR PREGNANCY:
Cashews have all the vitamins required for the expansion and development of the baby and are a perfect snack throughout physiological state. The anti-bacterial properties of cashews are useful in fighting against infections. Pregnancy will be a troublesome and wearying time for several ladies and also the made energy supply that cashews are will prove useful throughout this point. The high fiber content of cashew wacky is useful to fight symptoms of constipation and looseness of the bowels. Cashew give essential vitamins and different nutrients that your baby desires throughout its growing part. Cashews are famous to forestall gum and decay throughout maternity as well as cashews in your pregnancy diet helps maintain your macromolecule profile levels, particularly if you’re vulnerable to physiological state polygenic disease.
PREVENTION OF CANCER:
Cashew nutty have a high proportion of copper, Se and flavanols known as proanthocyanins that fight against cancerous cells. Proanthocyanin may be a pigment that stops tumor cells. Proanthocyanins and high copper in cashew nutty helps fight against cancerous cells and keeps you safe from carcinoma.



HAND SANITIZER



Hand sanitizer is a liquid or gel generally used to decrease infectious agents on the hands. Formulations of the alcohol-based type are preferable to handwashing with soap and water in most situations in the healthcare setting.

TO BEAT WITH CORONAVIRUS, we need a special type of handwash with 70%plus Alcohol.

Since the outbreak of COVID-19, sales of hand sanitisers have soared. It’s become such a sought-after product that pharmacies and supermarkets have started limiting the number that people can buy at one time. New York state has even announced it will start producing its own hand sanitiser to meet demand. Though hand sanitisers can help reduce our risk of catching certain infections, not all hand sanitisers are equally effective against coronavirus.
As with other viral respiratory infections – like the common cold and flu – the novel coronavirus (called SARS-CoV-2) is mainly spread when virus-laden droplets from a person’s mouth or nose are transferred to other people. However, a recent study has suggested that it can also spread through faeces.
Aside from inhaling droplets, you can also get respiratory viruses including SARS-CoV-2 by touching anything contaminated with the virus and then touching your face, in particular your mouth or nose. We touch our faces a lot without even realising it. A study from New South Wales found that people touch their faces about 23 times an hour
Washing with warm water and soap remains the gold standard for hand hygiene and preventing the spread of infectious diseases. Washing with warm water (not cold water) and soap removes oils from our hands that can harbour microbes.
But hand sanitisers can also protect against disease-causing microbes, especially in situations when soap and water aren’t available. They’re also proven to be effective in reducing the number and type of microbes.
There are two main types of hand sanitisers: alcohol-based and alcohol-free. Alcohol-based hand sanitisers contain varying amounts and types of alcohol, often between 60% and 95% and usually isopropyl alcohol, ethanol (ethyl alcohol) or n-propanol. Alcohol is known to be able to kill most germs.
Alcohol-free hand sanitisers contain something called quarternary ammonium compounds (usually benzalkonium chloride) instead of alcohol. These can reduce microbes but are less effective than alcohol.
Not only are alcohol-based hand sanitisers found to be effective at killing many types of bacteria, including MRSA and E coli, they’re also effective against many viruses, including the influenza A virusrhinovirushepatitis A virusHIV, and Middle East respiratory syndrome coronavirus (MERS-CoV).

Destroying viruses

Alcohol attacks and destroys the envelope protein that surrounds some viruses, including coronaviruses. This protein is vital for a virus’s survival and multiplication. But a hand sanitiser needs to be at least 60% alcohol in order to kill most viruses.
Hand sanitisers with less than 60% alcohol were also found to be less effective at killing bacteria and fungi and may only reduce the growth of germs rather than killing them outright.
And even hand sanitisers containing 60% alcohol can’t remove all types of germs. Studies have found that hand washing is more effective than hand sanitisers at removing norovirusCryptosporidium (a parasite that can cause diarrhoea), and Clostridium difficile (bacteria which cause bowel problems and diarrhoea).
With shortages leading some people to try and make their own hand sanitisers, it’s also important to know these might not be as effective as commercially available products.
Washing hands for 20 seconds with warm water works best. Hafiez Razali/ Shutterstock
If hands are visibly dirty, hand washing with soap and water is more effective than using alcohol-based hand sanitisers. Research has found that the detergent effect of soap and the friction of washing work together to reduce the number of microbes on our hands, as well as the dirt and organic materials.
Sneezing or coughing into your hands also requires more than just a pump of hand sanitiser to disinfect them. This is because if your hands are contaminated with mucous, the hand sanitiser might not work as well because mucous acts to protect microbes.
As a result, the best and most consistent way of preventing the spread of the coronavirus – and reducing your risk of contracting it – remains washing your hands with soap and water as a first choice, and avoiding touching your face as much as possible.
But alcohol-based hand sanitisers (with at least 60% alcohol) are a practical alternative when soap and water aren’t available. If you are using hand sanitiser then, just like when washing with soap and water, you need to make sure you cover your hands (including between your knuckles, wrists, palms, back of your hand and your fingernails) fully, rubbing it in for at least 20 seconds so it’s truly effective.


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CORONA VIRUS STARTED FROM WUHAN CITY IN CHINA AND SLOWLY SPREAD TO WHOLE WORK


Protection to be taken during COVID-19
Stay aware of the latest information on the COVID-19 outbreak, available on the WHO website and through your national and local public health authority. Many countries around the world have seen cases of COVID-19 and several have seen outbreaks. Authorities in China and some other countries have succeeded in slowing or stopping their outbreaks. However, the situation is unpredictable so check regularly for the latest news.
You can reduce your chances of being infected or spreading COVID-19 by taking some simple precautions:
  • Regularly and thoroughly clean your hands with an alcohol-based hand rub or wash them with soap and water.
    Why? Washing your hands with soap and water or using alcohol-based hand rub kills viruses that may be on your hands.
  • Maintain at least 1 metre (3 feet) distance between yourself and anyone who is coughing or sneezing.
    Why? When someone coughs or sneezes they spray small liquid droplets from their nose or mouth which may contain virus. If you are too close, you can breathe in the droplets, including the COVID-19 virus if the person coughing has the disease.
  • Avoid touching eyes, nose and mouth.
    Why? Hands touch many surfaces and can pick up viruses. Once contaminated, hands can transfer the virus to your eyes, nose or mouth. From there, the virus can enter your body and can make you sick.
  • Make sure you, and the people around you, follow good respiratory hygiene. This means covering your mouth and nose with your bent elbow or tissue when you cough or sneeze. Then dispose of the used tissue immediately.
    Why? Droplets spread virus. By following good respiratory hygiene you protect the people around you from viruses such as cold, flu and COVID-19.
  • Stay home if you feel unwell. If you have a fever, cough and difficulty breathing, seek medical attention and call in advance. Follow the directions of your local health authority.
    Why? National and local authorities will have the most up to date information on the situation in your area. Calling in advance will allow your health care provider to quickly direct you to the right health facility. This will also protect you and help prevent spread of viruses and other infections.
  • Keep up to date on the latest COVID-19 hotspots (cities or local areas where COVID-19 is spreading widely). If possible, avoid traveling to places  – especially if you are an older person or have diabetes, heart or lung disease.
    Why? You have a higher chance of catching COVID-19 in one of these areas.
  •  WHAT IS CORONA VIRUS?
    Coronaviruses are a large family of viruses that may cause illness in animals or humans.  In humans, several coronaviruses are known to cause respiratory infections ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). The most recently discovered coronavirus causes coronavirus disease COVID-19.
  • What is COVID-19?
  • COVID-19 is an infectious disease caused by the most recently discovered coronavirus. This new virus and disease were unknown before the outbreak began in Wuhan, China, in December 2019.
  • WHAT ARE SYMPTOMS OF CORONA VIRUS?
    The most common symptoms of COVID-19 are fever, tiredness, and dry cough. Some patients may have aches and pains, nasal congestion, runny nose, sore throat or diarrhea. These symptoms are usually mild and begin gradually. Some people become infected but don’t develop any symptoms and don’t feel unwell. Most people (about 80%) recover from the disease without needing special treatment. Around 1 out of every 6 people who gets COVID-19 becomes seriously ill and develops difficulty breathing. Older people, and those with underlying medical problems like high blood pressure, heart problems or diabetes, are more likely to develop serious illness. People with fever, cough and difficulty breathing should seek medical attention.
  • Should I worry about COVID-19?
    Illness due to COVID-19 infection is generally mild, especially for children and young adults. However, it can cause serious illness: about 1 in every 5 people who catch it need hospital care. It is therefore quite normal for people to worry about how the COVID-19 outbreak will affect them and their loved ones.
    We can channel our concerns into actions to protect ourselves, our loved ones and our communities. First and foremost among these actions is regular and thorough hand-washing and good respiratory hygiene. Secondly, keep informed and follow the advice of the local health authorities including any restrictions put in place on travel, movement and gatherings.Learn more
  • Protection measures for persons who are in or have recently visited (past 14 days) areas where COVID-19 is spreading
    Follow the guidance outlined above (Protection measures for everyone)
    Self-isolate by staying at home if you begin to feel unwell, even with mild symptoms such as headache, low-grade fever (37.3 C or above) and slight runny nose, until you recover. If it is essential for you to have someone bring you supplies or to go out, e.g. to buy food, then wear a mask to avoid infecting other people.
    Why? Avoiding contact with others and visits to medical facilities will allow these facilities to operate more effectively and help protect you and others from possible COVID-19 and other viruses.
    If you develop fever, cough and difficulty breathing, seek medical advice promptly as this may be due to a respiratory infection or other serious condition. Call in advance and tell your provider of any recent travel or contact with travelers.
    Why? Calling in advance will allow your health care provider to quickly direct you to the right health facility. This will also help to prevent the possible spread of COVID-19 and other viruses.
    • All the above data from who.com

MORE DATA ON CORONA:

Coronaviruses

Taxonomy

Coronaviruses and toroviruses are two virus genera within the virus family Coronaviridae, order Nidovirales. Coronaviruses are well-established pathogens of humans and animals while the toroviruses are recognized as causes of animal diarrhoea. Toroviruses have also been found in human faeces but their aetiological role remains unclear.
Coronaviruses are classified into three groups, initially based on antigenic relationships of the spike (S), membrane (M) and nucleocapsid (N) proteins and now re-enforced by viral genetic phylogeny (Box 57.1). The HCoVs 229E and NL63 are group 1 coronaviruses, while OC43, HKU-1 and SARS coronaviruses are classified in group 2. Group 3 coronaviruses are found in avian species. Genetic recombination readily occurs between members of the same and of different coronavirus groups providing opportunity for increased genetic diversity.
Efforts to identify the animal reservoir of SARS coronavirus led to the discovery of diverse bat coronaviruses in both group 1 and 2 that are closely related phylogenetically to different mammalian coronaviruses. It has been proposed that bat coronaviruses may indeed have been the ancestors of many mammalian coronaviruses. It is noteworthy that recent studies on the comparative evolution of animal and human coronaviruses have led to the conclusion that HCoV 229E and OC43, the causes of the common cold which are now globally endemic in humans, crossed species from their animal reservoirs (bats and cattle, respectively) to humans within the last 200 years, illustrating the fact that coronaviruses continue to cross species barriers and cause novel diseases.

Coronaviruses

Christopher J. Burrell, ... Frederick A. Murphy, in Fenner and White's Medical Virology (Fifth Edition), 2017

Abstract

Coronaviruses possess a distinctive morphology, the name being derived from the outer fringe, or “corona” of embedded envelope protein. Members of the family Coronaviridae cause a broad spectrum of animal and human diseases. Uniquely, replication of the RNA genome proceeds through the generation of a nested set of viral mRNA molecules. Until 2003, coronaviruses attracted little interest beyond causing mild upper respiratory tract infections. This changed dramatically in 2003 with the zoonotic SARS-CoV and the more recent emergence of MERS-CoV has confirmed the coronaviruses as significant causes of severe respiratory disease.

Human coronaviruses

Stephen N.J. Korsman MMed FCPath, ... Wolfgang Preiser MRCPath, in Virology, 2012

History

Coronavirus disease was first described in 1931, with the first coronavirus (HCoV-229E) isolated from humans in 1965. Until the outbreak of severe acute respiratory syndrome in late 2002, only two human coronaviruses (HCoV) were known – HCoV-229E and HCoV-OC43. Once the SARS coronavirus (SARS-CoV) had been identified, two further human coronaviruses were identified. Three groups of coronaviruses exist: group 1 (HCoV-229E and HCoV-NL63), group 2 (HCoVOC43 and HCoV-HKU1), group 3 (no human CoVs as yet). SARS-CoV is an outlier to all three groups, although some place it in group 2.
Fig. 1. Coronavirus.
Fig. 2. Replication cycle of coronaviruses.
Table 1. Classification
Order: Nidovirales
Family: Coronaviridae
GenusSpecies
CoronavirusHuman coronavirus 229E
Human coronavirus OC43
Human coronavirus NL63
Human coronavirus HKU1
Severe acute respiratory syndrome coronavirus
Human enteric coronavirus
TorovirusHuman torovirus
Table 2. Structure and replication
Structure
Positive sense single stranded RNA
Genome ∼30 000 nucleotides long
Pleomorphic viruses
80 × 160 nm diameter, with 12–24 nm surface projections (spikes) that cause the corona (Latin: crown) appearance
Major proteins:
S – spike
E – envelope
M – membrane
N – nucleocapsid
Table 3. Structure and replication
Replication

Coronaviridae

In Virus Taxonomy, 2012

List of other related viruses which may be members of the genus Alphacoronavirus but have not been approved as species

Carollia bat coronavirus 1FY2BA/Trinidad/2007(Ca-BatCoV 1FY2BA/Trinidad/2007)
Chaerophon bat coronavirus 40/Kenya/2006(Ch-BatCoV 40/Kenya/2006)
Chaerophon bat coronavirus 22/Kenya/2006(Ch-BatCoV 22/Kenya/2006)
Chinese ferret badger coronavirus DM95/03[EU769560](CFBCoV DM95/03)
Eptesicus bat coronavirus 65/RM/2006[EF544566](Ep-BatCoV 65/RM/2006)
Ferret coronavirus[GU338456; GU338457](FerCoV)
Glossophaga bat coronavirus 1CO7BA/Trinidad/2007(Gl-BatCoV 1CO7BA/Trinidad/2007)
Kenya bat coronavirus BtKY12[GQ920811](BatCoV BtKY12)
Kenya bat coronavirus BtKY21[GQ920819](BatCoV BtKY21)
Myotis bat coronavirus HKU6/HK/21/2005[DQ249224; DQ249247](My-BatCoV HKU6/HK/21/2005)
Myotis bat coronavirus D2.2/Germany/2007(My-BatCoV D2.2/Germany/2007)
Myotis bat coronavirus D8.38/Germany/2007(My-BatCoV D8.38/Germany/2007)
Myotis bat coronavirus 3/RM/2006[EF544567](My-BatCoV 3/RM/2006)
Myotis bat coronavirus 48/RM/2006[EF544565](My-BatCoV 48/RM/2006)
Myotis Bat coronavirus M.mac/Australia/CoV034/2008[EU834951](My-BatCoV M.mac/Aus/CoV034/2008)
Miniopterus bat coronavirus 088/Australia/2007[EU834952](Mi-BatCoV 088/Australia/2007)
Miniopterus bat coronavirus HKU7/HK/13/2005[DQ249226; DQ249249](Mi-BatCoV HKU7/HK/13/2005)
Nyctalus bat coronavirus VM366/NLD/2008(Ny-BatCoV VM366/NLD/2008)
Pipistrellus bat coronavirus D5.16/Germany/2007(Pi-BatCoV D5.16/Germany/2007)
Pipistrellus bat coronavirus D5.71/Germany/2007(Pi-BatCoV D5.71/Germany/2007)
Pipistrellus bat coronavirus VM312/NLD/2008(Pi-BatCoV VM312/NLD/2008)
Raccoon dog coronavirus GZ43/03[EU769559; EF192159](RDCoV GZ43/03)
Rhinolophus bat coronavirus A970/SD/2005Rh-BatCoV A970/SD/2005
Rousettus bat coronavirus HKU10/GD/183/2005(Ro-BatCoV HKU10/GD/183/2005)
Yellow-bellied weasel coronavirus GX/D726/2005[ABQ39953.1|](YWCoV GX/D726/05)

Coronaviridae

TURKEY CORONAVIRUS

Coronaviruses were first recognized in turkeys in the United States in 1951 and were associated with various enteric disease syndromes, variously termed “blue comb disease,” “mud fever,” “transmissible enteritis,” and “coronaviral enteritis.” The disease is present throughout the world, essentially wherever turkeys are raised. The virus can infect turkeys of all ages, but the most severe enteric disease is evident within the first few weeks of life. The onset is characterized by loss of appetite, watery diarrhea, dehydration, hypothermiaweight loss, and depression. Younger poults may die. The duodenum and jejunum are pale and flaccid, and the ceca filled with frothy, watery contents. The feces may be green to brown, watery, and may contain mucus and urates. The cloacal bursa is small (atrophic). Some turkeys may shed virus in their feces for up to 7 weeks, with virus transmission by the fecal–oral route. Turkey coronavirus infections also result in reduced egg production in breeder hens, and eggs may lack normal pigment and have a chalky shell surface. Interaction between turkey coronavirus and other agents (E. coliastrovirus, etc.) accentuate the disease.
Only one serotype of turkey coronavirus is recognized. Turkey coronavirus is classified, along with other avian coronaviruses, as a gammacoronavirus. Although there is high sequence identity (85–90%) in the three major viral proteins (polymerase, M, and N) of turkey coronavirus and avian infectious bronchitis virus, their S proteins are quite different, and turkey coronavirus likely represents a recombinant coronavirus containing a spike gene of unknown origin. Whether the origin of turkey coronavirus reflects altered enteric tropism or adaptation of an infectious bronchitis-like virus to the turkey, or whether infectious bronchitis virus is in itself a variant of an ancestral enteric avian coronavirus, is also unclear. Recently, bovine coronavirus was shown experimentally to infect turkey poults, but natural cases have not been described.
Turkey coronavirus can also be isolated in embryonated eggs of turkeys and chickens using the amniotic route of inoculation. No licensed vaccines for turkey coronavirus are available. Treatment involves supportive care, and is not specific.

Coronavirus Pathogenesis

Susan R. Weiss, Julian L. Leibowitz, in Advances in Virus Research, 2011

I Introduction

Coronaviruses, a family of viruses within the Nidovirus superfamily, were divided into three groups (1, 2, 3), originally based on antigenic reactivity, later confirmed by genome sequencing. Recently, a new taxonomic nomenclature was adapted by the International Committee on Taxonomy of Viruses (2009) (http://talk.ictvonline.org/media/g/vertebrate-2008/default.aspx). As such, coronaviruses are divided into three genera (alpha, beta and gammacoronaviruses), corresponding to groups 1, 2, 3, within the subfamily coronavirinae, within the family of coronaviridae, and within the order or superfamily of nidovirales. Coronaviruses cause diseases in a variety of domestic and wild animals as well as in humans. Probably the most well-studied coronavirus is the betacoronavirusmurine coronavirus (MuCoV), mouse hepatitis virus (commonly referred to as MHV) that has long provided model systems for the study of central nervous system (CNS) diseases such as encephalitis and multiple sclerosis (MS) and acute hepatitis. While most coronavirus infections cause the common cold in humans, the emergence of the agent for severe acute respiratory syndrome (SARS), the SARS-associated coronavirus (SARS-CoV), also a betacoronavirus, demonstrated the potential for further significant human diseases to result from coronavirus infections. Indeed, shortly after the identification of the SARS-associated human coronavirus (HCoV), new coronavirus were identified in association with more severe infections in humans, NL63 an alphacoronavirus, believed to cause bronchiolitis in children, and HKU1, a betacoronavirus, associated with chronic respiratory disease in the elderly (Pyrc et al., 2007). This review will concentrate on the model MuCoV and the human SARS-CoV.

Viral Diseases Transmissible by Kissing

Jacobo Limeres Posse, ... Crispian Scully, in Saliva Protection and Transmissible Diseases, 2017

4.1.3 Coronaviruses (CoV)

Coronaviruses are common viruses that can infect humans, and animals as diverse as bats and alpacas. There are a number of Human coronaviruses and they usually cause respiratory infections—mostly mild illnesses such as the common cold. However, several coronaviruses including the Middle East Respiratory Syndrome (MERS), especially seen in Saudi Arabia or visitors to that area, and Severe Acute Respiratory Syndrome (SARS), seen mainly in China and travelers from there, can cause more severe and sometimes life-threatening human infections.52,57 Coronaviruses that cause severe acute respiratory infections have >50% mortality rates in older and immunosuppressed people.58 WIV1-CoV, a virus similar to SARS, could also be poised to cause epidemics.59
People living with or caring for someone with a coronavirus infection are most at risk of developing the infection themselves. Coronavirus transmission is mainly oral–fecal and respiratory from small droplets of saliva or on fomites. Oral–urine and saliva transmission of MERS-CoV and SARS-CoV are also highly likely.11,12 Salivary cystatin D, a cysteine protease inhibitor, can inhibit replication of some coronaviruses.60 Although evidence is sparse, SARS-CoV appears to be transmitted primarily through saliva droplets. Kissing could constitute a route for transmission.

Respiratory Virus Vaccines

Andrew J. Broadbent, ... Kanta Subbarao, in Mucosal Immunology (Fourth Edition), 2015

Coronaviruses

Coronaviruses are frequent causes of the common cold, causing URTIs throughout the world, in all age groups, leading to millions of days of work and school absence, physician visits, and frequent inappropriate antibiotic use (Greenberg, 2011). Coronaviruses are transmitted by respiratory droplets and are reported to cause 7–30% of common colds, with a peak prevalence in late fall, winter, and early spring.
The first human coronaviruses (HCoV) to be recognized as significant respiratory pathogens, HCoV-229E and OC43, were identified in the 1960s (Greenberg, 2011). Whereas infection with the majority of coronaviruses is associated with self-limiting URT symptoms in otherwise healthy individuals, a coronavirus was identified as the agent responsible for SARS in 2003 (Drosten et al., 2003; Ksiazek et al., 2003). The SARS coronavirus (SARS-CoV) emerged in the Guangdong province of China in November 2002 and spread to 32 countries, leading to 8096 cases and 774 deaths worldwide by the time the outbreak was brought under control in June 2003 (WHO, 2004). Subsequently, heightened international surveillance for coronaviruses led to the identification of the strains HCoV-NL63, NH, and HKU1 in 2004–2005 (Greenberg, 2011) and the MERS coronavirus (MERS-CoV) in 2012 (Zaki et al., 2012). MERS-CoV was identified in 699 individuals between September 2012 and June 2014 with 209 fatalities (WHO, 2014).

Coronaviruses

E.J. Snijder, ... J. Ziebuhr, in Advances in Virus Research, 2016

Abstract

Coronaviruses are animal and human pathogens that can cause lethal zoonotic infections like SARS and MERS. They have polycistronic plus-stranded RNA genomes and belong to the order Nidovirales, a diverse group of viruses for which common ancestry was inferred from the common principles underlying their genome organization and expression, and from the conservation of an array of core replicase domains, including key RNA-synthesizing enzymes. Coronavirus genomes (~ 26–32 kilobases) are the largest RNA genomes known to date and their expansion was likely enabled by acquiring enzyme functions that counter the commonly high error frequency of viral RNA polymerases. The primary functions that direct coronavirus RNA synthesis and processing reside in nonstructural protein (nsp) 7 to nsp16, which are cleavage products of two large replicase polyproteins translated from the coronavirus genome. Significant progress has now been made regarding their structural and functional characterization, stimulated by technical advances like improved methods for bioinformatics and structural biology, in vitro enzyme characterization, and site-directed mutagenesis of coronavirus genomes. Coronavirus replicase functions include more or less universal activities of plus-stranded RNA viruses, like an RNA polymerase (nsp12) and helicase (nsp13), but also a number of rare or even unique domains involved in mRNA capping (nsp14, nsp16) and fidelity control (nsp14). Several smaller subunits (nsp7–nsp10) act as crucial cofactors of these enzymes and contribute to the emerging “nsp interactome.” Understanding the structure, function, and interactions of the RNA-synthesizing machinery of coronaviruses will be key to rationalizing their evolutionary success and the development of improved control strategies.

Noninfluenza Respiratory Viruses

Michael G. Ison, Nelson Lee, in Infectious Diseases (Fourth Edition), 2017

Nature

Coronaviruses are large, lipid-enveloped, positive-sense, single-stranded RNA virusesHuman coronaviruses (e.g. hCoV 229E, OC43, NL63) commonly cause mild upper respiratory tract infections, although occasionally result in more severe disease in immunocompromised individuals.77 However, two novel human coronaviruses, the severe acute respiratory syndrome-associated coronavirus (SARS-CoV), and a recently identified Middle East respiratory syndrome-associated coronavirus (MERS-CoV) may cause serious viral pneumonitis, leading to hospitalizations and deaths.78,79,289 Viral genome analyses revealed that SARS-CoV belongs to Group B and MERS-CoV belongs to Group C betacoronavirus, respectively, and both are closely related to coronavirus strains found in bats.78–80 Intermediate mammalian hosts, such as civet cats, have been implicated for SARS-CoV before its adaptation for human transmission, and emerging evidence (through virus or antibody detection) suggest that the dromedary camels are likely the host for MERS-CoV.78,79,81,290 The surface spike glycoprotein (S-protein) of coronaviruses is a key virulence factor which attaches the virus to host cells, determining its host range and tissue tropism, and it is a target of the neutralizing antibodies. SARS-CoV uses human angiotensin-converting enzyme 2 (ACE-II) as the primary cellular receptor; the human cellular C-type lectin (DC/L-SIGN) may be the alternative.82 MERS-CoV has been shown to bind to dipeptidyl peptidase 4, (DPP4; also called CD26), an interspecies-conserved protein found on the surface of several cell types, including the non-ciliated cells in human airways, which can explain its broadened host range and its ability to cause cross-species, zoonotic transmission.83