COVID-19 or SARS-CoV-2 Pandemic and its management: A Review
Anushree Singha Ray1 and Kuntal Bhattacharya2*
1Dr. Anushree Singha Ray, PhD, Former Research Scholar of Department of Zoology, The University of Burdwan, Golapbag, Burdwan- 713104, Purba Bardhaman, West Bengal, India, ORCID ID: 0000-0002-4379-
8142
2Dr. Kuntal Bhattacharya, PhD., Assistant Professor, Department of Zoology, Durgapur Government College, Jawaharlal Nehru Avenue, Durgapur- 713214, Paschim Bardhaman, West Bengal, India, ORCID ID: 0000-
0002-3921-7595
*Corresponding author: Dr. Kuntal Bhattacharya, Email: [email protected]
ABSTRACT
COVID-19 pandemic, a respiratory disease of unknown etiology, emerged as the critical global health havoc after the Second World War originating in Wuhan, Hubei Province, China. The SARS-CoV-2 or novel corona virus belongs to beta coronavirus (β-CoV) group. Till now, it has infected 4.3 million of people throughout the globe and took away the lives of 0.28 million. WHO puts COVID-19 as a Public Health Emergency of International Concerns (PHEIC). As of May 12, 2020, COVID-19 has infected 70,400 total cases and 1,693 deaths in India. SARS-CoV-2 is supposed to be a zoonotic virus having no vaccine or effective antiviral drugs till date. Thus, to put a stop to spreading of this contagious virus everyone should take intense precautionary measures included social distancing, isolation or quarantining of suspected COVID-19 positive individuals, maintaining proper respiratory hygiene etc. Though, asymptomatic carrier individuals can keep on the human to human transmission resulting in exponential rate of infection and several deaths. SARS-CoV-2 is more contagious than SARS-CoV-1 and MERS-CoV, but infections are mild and self treating, death rate is high in patients of COVID-19 with co-morbidities. The global economy is on the way of destruction due to COVID-19 pandemic as well as it has many social impacts also. In this review article we have summarizes the developing phenomenon of SARS-CoV-2 pandemic with regards to its epidemiology, possible origins, genomic structure, transmission, symptoms, pathogenesis, social impact and prevention and control measures based on acquainted literature.
Keywords: Coronavirus, Covid-19, epidemiology, pandemic, pathogenesis, respiratory syndrome, socio-economic.
Introduction
In the late December 2019, a global awakening happened into a reality of a pandemic of the Coronavirus Disease (Covid-19) caused by a highly transmissible Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) originated from the Wuhan City of Hubei Province, People’s Republic of China with an unknown etiology (Riou and Althaus, 2020). Virus diseases are itself a gripe threat to human population. Before Coronavirus the world has faced several viral pandemics and epidemics. In a span of a decade, severe acute respiratory syndrome Coronavirus (SARS-CoV-1), H1N1 influenza and the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) emerged as public health crisis in 2003, 2009 and 2012
respectively. Now, this coronavirus outbreak may be associated with the revelation of the first person in the seafood market of Wuhan City as notified by the National Health Commission of China (Li et al., 2020).
World Health Organization has affirmed that the large evidence of pneumonia cases were reported early and after that it was inveterate as the 2019 novel Coronavirus (2019-nCoV) by the province on 7th of January, 2020 (WHO, 2020a). Genetic sequence of SARS-CoV-2 was analyzed and shared to other countries on January 12, 2020 to build up unambiguous diagnostic kits. WHO has declared a name for the coronavirus disease, Covid-19 on 11th February, 2020. On 11th March, based on the alarming levels of spreading, inaction and severity WHO has declared that Covid-19 is a pandemic and be a Public Health Emergency of International Concern (PHEIC). As of April 26, 2020, 3,175,207 confirmed cases and 224,172 deaths were reported globally by the situation report 102 of WHO (WHO, 2020b). In India, till now 26,917 confirmed cases and 826 deaths were reported by WHO in situation report 13 which is hiked by 10,801 cases and 307 deaths by one week only (WHO, 2020c).
Till now Coronavirus is affecting 212 countries and territories throughout the globe and two international conveyances also.
After being engulfment of the world by the pandemic, researchers are heavily trying to make a vaccine or to control it. There is extensive research on the way that leads to development of disease diagnostic kit, virus genome sequencing, categorization of the disease and its transmission, development of feasible efficient vaccine in close prospect to eliminate the continued infection of Coronavirus.
Here, through the present study, we methodically review the budding phenomenon of Covid- 19 pandemic with respects to its epidemiology, possible origins, distinctive genomic organization, transmission, pathogenesis, symptoms and socio-economic aspects from the evidence of literature review. Key preventive measures and management implied throughout the globe will also be enlightened in this review article to portray the real time information on the pandemic and act as valuable literature source for the subsequent research endeavours.
Epidemiology
In Wuhan City, China on 29 December 2019, first four cases of respiratory syndrome with unknown etiology were identified among the people who were related to Huanan seafood market (Li et al., 2020). Thereafter, researchers observed that 49% -66% patients had some kind of contact history with the seafood market. At first it was speculated that the first case of infection came from some wild animals, especially bats, according to WHO, after the
sample taken from Huanan seafood market were tested positive for novel coronavirus. In that seafood market various living wild animals were on sale, including bats. From the previous research it is known that the bats are the host of more than 30 coronaviruses (Phan, 2020), so it can be a possible origin of COVID-19.
Rate of transmission of disease from one person to another is an imperative aspect of an epidemic. A sudden rise of the frequency of infected persons with no contact history with wildlife or no visiting history to Wuhan proved that it has a high transmissibility from person to person (Gralinski and Menachery, 2020), so, sooner or later man to man transmission by close contact was identified as the secondary grounds of SARS-CoV-2 infection.
In case of infectious disease, the basic reproduction number R0 is the important property of disease transmission. In an entirely vulnerable populace, R0 is generally used throughout the early hours of an epidemic to quantify the mean rate of secondary infection. Due to its higher rates of transmissibility than SARS-CoV, the novel coronavirus’s effective reproductive number (R0) is 2.9 which is much higher than recorded effective reproductive number (R0) of SARS i.e. 1.77. Human to human transmission can occur when the reproductive number (R0) is more than one. Thus, a sustainable and powerful secondary transmission route was established (Riou and Althaus, 2020; Liu et al., 2020). Beside this there are many different factors shaping the value of R0, viz. particular models used for estimation, period of estimation and datasets (Tang et al., 2020). In this case it is also a noteworthy finding that asymptomatic patients can also be able to spread the infection (Rothe et al., 2020) along with the worth mentioning super communicator who can transmit the disease to more than 100 persons (Wang and Jin, 2020).
Many researchers have reported that the average incubation period of novel coronavirus is ranging from 2-11 days with a maximum incubation period of 24 days (Guan et al., 2020).
There were so many reported cases in China, where the patients have no contact record with the Huanan seafood market as well as the cases of infection of the medical staff specified that human to human transmission occurs generally through close contact or air droplets comes out from coughing or sneezing (Gralinski and Menachery, 2020; Chan et al., 20020, Rothe et al., 2020).
Both normal and immunosuppressed populations are at risk of the exposure to this novel coronavirus. Report suggests that the median age of most of the patients was 59 years ranging from 51-89 years (Xu et al., 2020), where the majority of the patients were male (50-75%).
Age of the infected patients ranging from 25-89 years with most patients aged between 35-55 years, whereas there are very fewer cases among the children and infants (Huang et al., 2020,
Chen et al., 2020). Reported median age of the patients who died due to Covid-19 is 75 years (ranging between 48 – 89 years). People having low immunity, mainly old aged persons and those with cardiac problem, renal or hepatic dysfunction or have chronic co-morbidities and patients having any surgery history were observed to be the highest susceptible group (Li et al., 2020). Through meticulous literature review it came to know that roughly 25.2–50.5%
Covid-19 patients had one or more underlying diseases including diabetes, hypertension, cardiovascular disease, malignancy and or chronic obstructive pulmonary disease (Guan et al., 2020).
Origin of the virus
To take up some preventive strategies at first it is important to be aware about the origin and transmission of the novel virus. This SARS-CoV-2 or the novel coronavirus belongs to the Orthocoronavirinae subfamily, Coronaviridae family and Nidovirales order. Within the subfamily Orthocoronavirinae, four genera was present namely Alpha- coronavirus (α-CoV), Beta coronavirus (β-CoV), Gamma coronavirus (γ-CoV) and Delta coronavirus (δ-CoV) according to the classification based on International Committee on Taxonomy of Viruses (ICTV). It has crown-like spikes on the outer surface, represents corona, thus, it was named as a Coronavirus (65-125 nm in diameter). Of the four genera, both α-CoVs and β-CoVs are primarily known to transmit a disease to mammals, whilst δ-CoVs and γ-CoVs can infect birds (Banerjee et al., 2019). Previously thrived SARS-CoV-1 and MERS-CoV are of β-CoV.
Among these, 6/7 types of corona viruses can create respiratory complications in humans (HCoVs). Among them the HCoV-229E and HCoV-NL63 strains of α-CoV and HCoV- HKU1 and HCoVOC43 strains of β-CoV has low infectivity, which can produce common cold like placid respiratory infection. On the other hand, SARS-CoV and MERS-CoV belong to the β-CoV genera can cause life threatening severe respiratory infectivity (Yin and Wunderink, 2018).
During the late December in 2019, the novel coronavirus puts its claw into the human populations. It was suspected that the virus first get transmitted from a 50,000 square meters of animal and seafood market of Huanan in Wuhan city of China. In this market various living and non living animals along with the seafood were sold for human consumption. It was speculated that the first 27 coronavirus cases instigated from the Southern China Seafood Market, so there is a high chance of infection from the live wild animals which are placed in a close proximity with the human (Zhu et al., 2020; Tan et al., 2020). There is 96.2%
similarity of the genomic sequence of SARS-CoV-2 with the genomic sequence of bat CoV
RaTG13. In bat CoV RaTG13 a short RNA-dependent RNA polymerase (RdRp) region was analogous to SARS-CoV-2 (Guo et al., 2020; Wu et al., 2020). Even the previous report says that there is approximately 88% nucleotide similarity with two virus of Bat (Rhinolophus affinis) namely SLCoVZC21 and SL-CoVZC45 (Guo et al., 2020; 17, 18). It clearly indicates that the SARS-CoV-2 have common ancestry with bat and may be originated from Chinese chrysanthemum bat. The bats are the natural reservoir of previously existed SARS-CoV and MERS-CoV.
Previously researchers focused on some raccoon dogs (Nyctereutes procyonoides) and palm civets (Paguma larvata) as a key reservoir of SARS-CoV-1, among these the sample isolated from the civets presents on that food market showed positive signifying that the civet palm cat might be intermediate hosts of it (Kan et al., 2005).
Based on the evidence of evolutionary analysis and reports of genome sequencing and as a natural reservoir of coronaviruses, it can suggest that bat may be the probable origin of the SARS-CoV-2. But they can transmit the virus to humans via some unspecified intermediate hosts like pangolins, palm civets, snakes, dromedary camels etc. (Guo et al., 2020). After sequencing of metagenomic data of pangolin, 99% of sequence similarity was found with SARS-Co V-2 (>1000 samples metagenomic data) (Guo et al., 2020). So, it also been proposed that the pangolin may play a role in the viral infection as an intermediate host. In an experiment, this novel coronavirus was derived from the restructuring of pangolin- coronavirus like virus and a Bat-CoVRaTG13 (Xiao et al., 2020). But it is clear from the molecular and phylogenetic analyses that SARS-Co V-2 was not derived directly from the pangolin-coronavirus like virus, so, it is not the only intermediate host of SARS-Co V-2 (Liu et al., 2020).
From the genetic sequences of all the known coronaviruses it can proposed that SARS-CoV-2 has most similar codon usage with snakes (Ji et al., 2020). Snakes often hunt bats in the forest and also sold on that seafood market in Wuhan. There is a possibility that the SARS-CoV-2 infected human from bats with the involvement of other intermediate hosts.
From the present evidence it can be said that the bats are the most probable original reservoir of the virus. But, the mechanism of adaptation of virus in both cold-blooded and warm- blooded hosts remains unknown to scientists (Ji et al., 2020).
Structure and genomic organization of virus
Genome of identified novel corona virus has been sequenced and found that there is 86.9%
similarity of its genome with the previously existed SARS-CoV genome (Chang et al., 2020).
Some phenotypic methods like electron microscopy, virus culture and serological studies are employed to identify the novel virus. Coronaviruses were pleiomorphic, enveloped viruses having positive-sense genome with single-stranded RNA which is 26 to 32 kbs in length.
Various researchers have reported that there are four structural proteins like spike (S), envelope (E), membrane (M) and nucleocapsid (N).
Its genome contains highly variable open reading frames (ORFs). One-third of the genome encodes these proteins and some other helper proteins. Two-third of the genome is responsible to code for the viral polymerase which is RNA-dependent RNA polymerase (RdRp) and two types of non-structural proteins namely ORF1a-ORF1b (Sahin et al., 2020).
Among the different genes of SARS-CoV-2, orf1ab is the largest gene. The orf1a and orf1ab gene encodes for two polyprotein, pp1a and pp1ab protein which translate 10 and 15 non structural proteins (nsps) respectively (Wu et al., 2020 and Lu et al., 2020). The spike glycoprotein of novel coronavirus is a mixture of bat SARS-CoV and an unknown Beta-CoV (Li et al., 2020). Researchers were reported that during entry into the host cell SARS-CoV-2 uses the same mechanism and ACE2 (angiotensin-converting enzyme 2) cell receptor like SARS-CoV (Xu et al., 2020). The binding affinity for ACE2 was enhanced due to a single mutation (N501T) in spike proteins of SARS-CoV-2 (Wan et al., 2020). While there is an evolutionary close relation between the SARS-CoV-2 and SARS-corona viruses, it is a worth mentioning that the 8a protein is absent in SARS-CoV-2 and there is a fluctuation in the number of amino acids in 8b and 3c protein also (Hui et al., 2020).
The surface S protein is responsible for its crown like appearance. During the entry point of the virus into the human cell, viral genome can enter the cell when the S protein interacts with the sensitized cell of the body. Various structural and non-structural polypeptide genes were encoded in the cytoplasm upon the entry of the viral genome. Then, the virus structure is reformed by the alterations of S protein coding genes. The E and M types of proteins play the role of small transmembrane proteins and cloning and recombinant proteins production was done by N protein.
Transmission of Covid-19
The novel coronavirus isolated from the affected patients in China was suggested to be originated from the seafood market of Wuhan possesses zoonotic transmission procedure, i.e.
from animal to human. Due to enormous similarity with the SARS-CoV-2 with bat CoV- RaTG13 it supposed that bat is the primary host and may be pangolin is the intermediate host.
It can easily move across species (Guo et al., 2020). During last few decades it came to
known to us that coronaviruses can infect mice, rats, dogs, cats, horses, pigs and cattle, and occasionally these animals can transmit the virus to human. In spite of the closing of the seafood market, there is a spike of highly increasing cases of Covid-19 proved that there is human to human transmission or communal spreading (Chan et al., 2020; Huang et al., 2020a; Nishiura et al., 2020).
BAT
Figure 1. A conceptual diagram on the possible route of transmissions
Zoonotic transmission is the primary source as per the reported data. However, human to human secondary transmission is the major route of transmission that involves both direct contact and contact through respiratory droplets. Transmission through fomites is also seen.
Respiratory virus can be transmitted via droplets of varying sizes, i.e. the droplets of >5-10 um in diameter are called as respiratory droplets and the droplets of <5 um in diameter are referred as droplet nuclei. Among the human populations the SARS-CoV-2 is primarily dispersed through respiratory droplets (Figure 1), which can be generated through coughing, sneezing or talking. Disease transmission can occur via those droplets when a person is in close contact, approximately within 1 meter to an infected person with the symptoms of coughing or sneezing. Disbursed droplets containing SARS-CoV-2 can travel upto 3 feet (Guo et al., 2020). But researchers have reported that the virus can infect a healthy person in a radius of 6 feet. SARS-CoV-2 containing droplets can be attached at the mucous membranes of the eyes (conjunctiva), nose or mouth of another person. A current report showed that ocular surface can also carry the virus and can transmit the infection to others (Lu et al., 2020a). Beside this coronavirus can spread by handshaking with infected person and touching the face including eyes, nose or mouth repeatedly. In coughing and sneezing droplets the virus can endure for 2 hours to few days on any surface or floor.
BAT INTERMEDIATE
HOST
HUMAN
INVISIBLE ROUTE FOMITES
HUMANS
VISIBLE ROUTES Respiratory Droplets
Hand shaking and other touches
Some researchers stated that there was gastrointestinal infection by SARS-CoV-2 which may be present in faeces, so a fecal-oral pathway may also be a possible way for the transmission of Covid-19, but till date there is no report of the fecal-oral transmission (Wang and Jin, 2020). There is another way of transmission of this disease via fomite transmission i.e.
transmission of virus by contacting some virus containing object including stethoscope, paper, mobile, hair etc. Asymptomatic carrier persons can also transfer the virus to healthy person via unintentional spreading called ‘‘hidden transmission” (Chan et al., 2020).
Till now there is no study reports the food borne transmission of SARS-CoV-2 as well as no proof of survival of the virus in food.
Symptoms
All the existing corona viruses can infect the respiratory and upper gastrointestinal tract of the mammals and birds. Here we are going to discuss about the symptoms of the Covid-19 caused by the SARS-CoV-2. Complete clinical features of COVID-19 are unknown to the researchers till now. The symptoms of the Covid-1 may be from mild to moderate. The RNA virus can mutate slowly by replication using RNA-dependent RNA polymerase, posturing a challenge to the society for its treatment and management. In general, after 2 to 14 days of infection the symptoms of COVID-19 may be developed. But, in some cases, the symptoms may be witnessed after 27 days. Researchers have reported that on average it takes 5-6 days to develop the symptoms (Li et al., 2020). The incubation period of virus may be different from severe to mild case and it depends on the age and immunity of the patient. The incubation period is shorter as 11.5 days among the patients who are older than 70 years than 20 days in case of patients younger than 70 years (Wang et al., 2020a). The disease symptoms of COVID-19 are typically similar to a common cold and influenza and usually do not turn to severe. Though, the people suffering from underlying diseases like diabetes, cardiac problem, lung, kidney, cancer and other diseases may develop different mild to severe forms leading to death. Some people have no to mild pneumonia like symptom. The common symptoms of COVID-19 infection are dry cough, high fever and fatigue. Some other less common symptoms are muscle aches, headache, sneezing, nasal congestion, sore throat, conjunctivitis, respiratory problems, diarrhoea, rash on skin, loss of taste and smell, discolouration of fingers or toes etc. (Huang et al., 2020; Hui et al., 2020). According to WHO, among the 70,000 cases in China there was 88%, 68%, 38% and 4% cases had fever, dry cough, sore throat and diarrhoea as symptoms which are much more similar to the symptoms of SARS-CoV and MERS-CoV. In addition severe shortness of breath develops among 20% cases. (Yang et al., 2020a). Diarrhoea is a new symptom of COVID-19 reported
by the researchers recently. Symptoms related to the digestive system like diarrhoea, loss of appetite, vomiting and other major ailments of the digestive system have been reported in case of many patients. These symptoms may appear due to abolition of the normal gastrointestinal bacteria by SAR-CoV-2 (Zhang and Xu, 2020).
In COVID-19 patients higher counts of cytokines, chemokines, leukocytes and high levels of plasma pro-inflammatory cytokines and C-reactive protein have found. Some patients make progress easily while others may take time to recover depending upon the age and health conditions of the patients. About 80% people don’t need the hospital treatment to recover.
About 1 out of 5 COVID-19 patients may develop severe respiratory infection and difficulty breathing needing the ventilator (WHO, 2020).
Depending upon the symptoms, travel history to an affected country or place and the exposure to an infected person the medical diagnosis of COVID-19 were done. Among several published testing procedures for COVID-19 by WHO, most common testing procedure is employment of real-time reverse transcription polymerase chain reaction (RT- PCR) (Huang et al., 2020). For the test, respiratory samples may be collected by several ways like nasopharyngeal swab or sputum collection. Usually, within a few hours to two days results may be available after testing.
To detecting SAR-Cov-2 in a symptomless person, two blood samples have to take two weeks apart and identify the antibodies in the blood. These antibodies are released shortly after infection, and may be identified by the blood test.
Pathogenesis
Among the reported case, the percentage of death of COVID-19 was approximately 10.69%
on May 5, 2020 and the median age of the deaths was above 60 years. Corona viruses can effortlessly move among the species. During transmission it first attacks the lining cells of the throat, trachea and lung. The lining cells then transforms into virus producing site and generate enormous viruses that infect other cells. During this time high temperature and feeling of dissatisfaction may be occur due to the immune response of the body to the virus.
Immune systems send the signal to the body to discharge cytokines. However, disruption of the immune system by the virus results inflammation of the body (Lei et al., 2020). If severe pneumonia occur, lung alveoli begin to fill with water, travelling of oxygen to the blood may hamper which causes shortness of breath. SAR-CoV-2 don’t attack the lungs only, it may infect other important organs in the body to including kidneys, which results to organ failure (Li et al., 2020b). An enzyme Angiotensin Converting Enzyme 2 (ACE2) found in the membranes of the cells of lungs, kidneys and seminiferous ducts of the testis, may highly
express in the renal tubular cells and testicular cells. A current report has published that the virus might affect those cells by directly binding to such ACE2 bearing cells due to elevated expression of ACE2 in the cells and can damage the kidney and testicular tissue of patients (Fan et al., 2020).
To enter into the host cell the S1 spike glycoprotein of SARS-CoV-2 tightly attaches to ACE2 receptor of the cell (Lu et al., 2015). Mainly upon cleavages of ACE2 and transmembrane protease/serine subfamily member 2 (TMPRSS2) specifically in airway and alveolar areas, virus entry can possible.
These proteins have mutant nature, specially spike glycoprotein (S), as well as they are evolutionary changed after the previous outbreak of coronavirus (Li, 2016) but showed high positive selection in case of both intraspecies and interspecies transmissions (Song et al., 2005; Woo et al., 2009). Though, the genomic sequence of SARS-CoV-2 possesses little difference with SARS-CoV, the ORFs and major structural proteins, the spike (S) protein, has 76% similarity (Malik et al., 2020). The S protein has two domains, S2 and S1, of which the receptor binding domain (RBD) of S1 region has stronger affinity with the ACE2 (Chu et al., 2020). The spike protein has high variability (Salata et al., 2020), can easily recognize the ACE2 receptors present in mouse, bat, civet and raccoon dog including human, so, this virus can easily move across the species, enhances the risk of interspecies transmission (Hou et al., 2010; Sheahan et al., 2008; Xu et al., 2009).
It was reported that the infected patients showed higher count of leukocyte, and amplified amount of plasma pro-inflammatory cytokines. The respiratory system targeting virus SARS- CoV-2 causes COVID-19 infection develops pneumonia, RNAaemia (viral load in serum), acute cardiac injury and ground-glass opacities of lungs in severe cases (Huang et. al., 2020).
Considerably elevated levels of cytokines and chemokines were noticed in affected patients included IFNγ, IL1RA, IL1-β, IL7, IL8, IL9, IL10, FGF2, GCSF, GMCSF, IP10, MCP1, MIP1α, MIP1β, PDGFB and TNFα etc (Huang et. al., 2020).
Preventive measures and management of disease
Far-reaching health and infectivity control measures against COVID-19 i.e. disease prevention and management are immediately required to limit the man-to-man transmission or to control the global outbreak of the virus (song et al., 2020), it is an utmost important concerns to researchers nowadays. To control this pandemic, the cooperative efforts of the public and the government are equally needed with the health care worker and researchers.
Care of susceptible population
In this context, susceptible populations like children, old age people and health workers need exceptional attention to protect them or to diminish the COVID-19 transmission. Old people have weak immune system that triggered the viral infection to promptly develop that leads to death other than younger people (Wang et al., 2020; Li et al., 2020). There must be some way to provide the sanitizing agents to people to sanitize hands and other objects routinely.
Travellers screening
From the earlier cases it is reported that infected travellers can spread the disease to healthy people by knowingly or unknowingly. So, traveller screening is robustly highlighted to give a paramount importance to isolate the SARS-CoV-2 infection from travellers (Kim et al., 2002). It’s a way to restrain the spreading of COVID-19 in other geographical regions. Many countries including China, US, India have put into practice the traveller screenings as the major prevention and control method to curtail the spreading of the virus (Carlos et al., 2020).
Conversely, traveller screening has its limitation also. As the SARS-CoV-2 has longer incubation period, the travellers doesn’t show any symptom and they feel enough healthy to travel from one country to another. They even don’t know that they are infected with this novel coronavirus; so, concurrently it becomes so difficult to isolate the infected persons (Lauer et al., 2020).
Personal care
To control this situation and to stop the spreading of the virus everyone should take proper measures and personal hygiene throughout the time. Cleaning of your hands often with soap or alcohol based hand-rub is much important. To prevent the spread of COVID-19 one should maintain a safe distance to person who have symptoms like sneezing and coughing.
Maintaining a proper respiratory etiquette means to cover your nose and mouth with your elbow or with tissue or cloth during coughing or sneezing, covering of mouth and nose with masks when needed. Restrain yourself to touch your face especially eyes, nose and mouth without washing your hands. One should take regular care to sanitize home or hospitals or any high touch object sincerely to combat with this catastrophe. Interactions with COVID-19 suspecting patients or persons with symptoms like coughing, sneezing or breathing problem should be avoided. If feeling unwell must stay at home, and it is advisable that not to use any means of public transport like train, bus, metro, taxi, airbus etc.
Simple house cleaning disinfectants may kill the virus, regular cleaning of the surface or floor with the disinfectants may control the viral epidemic. Besides some chemicals like Alcohols, Aldehydes, Phenolics can act as microbicides and may effective against coronaviruses
(Sattar, 2020). The washable foodstuffs should wash thoroughly before cocking and drinking of plenty of lukewarm water may help in this regard.
There are guidelines for healthcare providers, medical staff, researchers and public health individuals in the website of WHO or local government official website (Jin et al., 2020).
Those persons, who were not following the directions or not taking the advice from local government or WHO seriously, got sick. Hence, everyone should strictly maintain the preventive measures, managements and isolation or quarantine devoid of any religious inconsistency; or else the circumstances will get worse.
Social impact
In the recent circumstances of COVID-19 whole world has faced a socio economic crisis; it has affected approximately all sectors of the society. The global loss is cannot be estimated.
Coronavirus cases have brutally demobilized the worldwide economy. Airlines and tourism industry face a millions of dollars loss due to suspension of travel due to COVID-19. Besides airline, railway, bus, metro, vehicle transport is totally suspended with some exemption to special fields. Industries of non essential commodities are suffered more. In the era of globalization there are many countries that produce various items including medicines, machines, motor vehicles, computers, mobiles, etc. the component of those items may produce in one country and they get assembled in another country. So, if one chain breaks it can affect the whole world. Due to nationwide lockdown in different countries, whole world is socio-economically affected. Another difficulty have hit many countries i.e. unemployment in different sectors and as a result of it loss of productivity. Many countries have suspended the classes of schools, colleges, and Universities; this is a big disadvantage for students.
Some social functions like marriage parties, business meetings, scientific conferences and sports events are suggested to avoid put a big impact on society. In case of India, its total growth is approximated to have dipped beneath 5% for the financial year 2019-20 amidst nationwide lockdown. This lockdown have a direct effect on GDP of each country.
Conclusion
The COVID-19 originated from the seafood market of Wuhan in China during late December and became a pandemic, an international crisis. Due to nationwide lockdown in different countries, the worldwide economy is at a stake. The virus SARS-CoV-2 rapidly spread among the 212 countries. Millions of people get infected by the novel coronavirus of which US is the most affected country in the world with thousands of deaths. While the country of origin of the virus, China have managed successfully to maintain the plateau stage owing to new incidence of COVID-19, rest of the world are growing affected cases daily. Mainly it is
respiratory disease, showed flu like symptoms, patients develop pneumonia and in worst case it leads to death. Till date research is going on to find its exact zoonotic origin, develop its vaccine or to implement any medicine of it. Hydroxylchloroquine and azithromycin with a combination of antiviral drugs may be prescribed to treat people depending on the patient's symptoms and conditions. There are very few examples of alleviations of patients with the antiviral treatment using Ritonavir, Remdesivir, Oseltamivir and Lopinavir etc. So, it is better to follow the prevention and control measures to avoid being affected or to spreading. In this regards our new generations has to be enough educated in science and technology to combat with any such calamity in future; if any. And at last, using wild animals as a food should be banned for always and over.
Right now, strenuous efforts of all people with the health care provider and government as well are needed to limit the spreading of infection. Citizens of different countries are advisable to comply with the nationwide lockdown and maintain the social distancing procedure during this crisis period, to defeat this highly contagious virus.
Acknowledgment
Scientific publications of all the authors related to COVID-19 are thankfully acknowledged.
Conflict of interests
We have no conflict of interest.
References:
1. Riou J, Althaus CL, 2020. Pattern of early human-to-human transmission of Wuhan 2019 novel coronavirus (2019-nCoV), December 2019 to January 2020.
https://doi.org/10.2807/1560-7917.ES.2020.25.4.2000058.
2. Li Q, Guan X, Wu P, Wang X, Zhou L, et al. Early transmission dynamics in Wuhan, China, of novel coronavirus-infected pneumonia. N Engl J Med 2020;
https://doi.org/10.1056/NEJMoa2001316.
3. WHO, Coronavirus disease 2019 (COVID-19) Situation Report – 52. 2020a.
4. WHO, Coronavirus disease 2019 (COVID-19) Situation Report – 102. 2020b.
5. WHO, Coronavirus disease 2019 (COVID-19) Situation Report – 13. 2020c.
6. Phan T. Novel coronavirus from discovery to clinical diagnostics. Infect Genet Evol 2020; 79:104211.
7. Gralinski LE, Menachery VD. Return of the coronavirus: 2019-nCoV. Viruses 2020;
12: 135. https://doi.org/10.3390/v12020135.
8. Liu Y, Gayle AA, Wilder-Smith A, Rocklov J. The reproductive number of COVID- 19 is higher compared to SARS coronavirus. J Travel Med 2020;
https://doi.org/10.1093/jtm/taaa021.
9. Tang B, Bragazzi NL, Li Q, Tang S, Xiao Y, Wu J. An updated estimation of the risk of transmission of the novel coronavirus (2019-nCov). Infect Dis Model 2020; 5:
248–255.
10. Rothe C, SchunkM, Sothmann P, Bretzel G, Froeschl G,Wallrauch C, et al.
Transmission of 2019-nCoV infection from an asymptomatic contact in Germany.
New Engl J Med 2020; https://doi. org/10.1056/NEJMc2001468.
11. Wang G, Jin X. The progress of 2019 novel coronavirus event in China. J Med Virol 2020; https://doi.org/10.1002/jmv.25705.
12. Guan Wj, Ni ZY, Hu Y, Liang WH, Ou CQ, He JX, et al. Clinical characteristics of 2019 novel coronavirus infection in China. medRxiv 2020;
https://doi.org/10.1101/2020.02.06.20020974: 2020.02.06.20020974.
13. Chan JF, Yuan S, Kok KH, To KK, Chu H, Yang J. et al. A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster. Lancet 2020; 395: 514–523.
14. Xu XW, Wu XX, Jiang XG, Xu KJ, Ying LJ, Ma CL, et al. Clinical findings in a group of patients infected with the 2019 novel coronavirus (SARS-Cov-2) outside of Wuhan, China: retrospective case series. BMJ (Clin Res Ed) 2020; 368: m792.
15. Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet (London, England) 2020; 395: 497–506.
16. Chen N, Zhou M, Dong X, Qu J, Gong F, Han Y, et al. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. Lancet 2020; 395: 507–513.
17. Banerjee A, Kulcsar K, Misra V, Frieman M, Mossman K. Bats and coronaviruses.
Viruses 2019; 11 pii: E41. doi: 10.3390/v11010041.
18. Yin Y, Wunderink RG. MERS, SARS and other coronaviruses as causes of pneumonia. Respirology 2018; 23: 130–137.
19. Zhu N, Zhang D, Wang W, Li X, Yang B, Song J, et al. A novel coronavirus from patients with pneumonia in China, 2019. N Engl J Med 2020; 382: 727–733.
20. Tan W, Zhaob X, Ma X, Wang W, Niu P, Xu W, et al. A novel coronavirus genome identified in a cluster of pneumonia cases—Wuhan. China 2019–2020. 2020; (2): 61–
62.
21. Guo YR, Cao QD, Hong ZS, Tan YY, Chen SD, Jin HJ, et al. The origin, transmission and clinical therapies on coronavirus disease 2019 (COVID-19) outbreak – an update on the status. Mil Med Res 2020; 7: 11.
22. Wu A, Peng Y, Huang B, Ding X, Wang X, Niu P, et al. Genome composition and divergence of the novel coronavirus (2019-nCoV) originating in China. Cell Host Microbe 2020;
23. Kan B, Wang M, Jing H, Xu H, Jiang X, Yan M, et al. Molecular evolution analysis and geographic investigation of severe acute respiratory syndrome coronavirus-like virus in palm civets at an animal market and on farms. J Virol 2005; 79(18): 11892–
900.
24. Xiao K, Z.J., Feng Y, Zhou N, Zhang X, Zou JJ, et al. , Isolation and characterization of 2019-nCoV-like coronavirus from malayan pangolins. bioRxiv 2020;
25. Ji W, et al. Cross-species transmission of the newly identified coronavirus 2019- nCoV. J Med Virol 2020; 92 (4), 433–440.
26. Chang L, Yan Y, Wang L. Coronavirus disease 2019: coronaviruses and blood safety.
Transfus Med Rev 2020;
27. Sahin AR, Erdogan A, Agaoglu PM, Dineri Y, Cakirci AY, Senel ME, et al. Novel coronavirus (COVID-19) outbreak: a review of the current literature. EJMO 2019;
28. Lu R, Zhao X, Li J, Niu P, Yang B, Wu H, et al. Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding. Lancet 2020; 395(10224): 565–74.
29. Xu X, Chen P, Wang J, Feng J, Zhou H, Li X, et al. Evolution of the novel coronavirus from the ongoing Wuhan outbreak and modeling of its spike protein for risk of human transmission. Sci China Life Sci 2020; 1–4.
30. Wan Y, Shang J, Graham R, Baric RS, Li F. Receptor recognition by novel coronavirus from Wuhan: an analysis based on decade-long structural studies of SARS. J Virol 2020;
31. Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, et al. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus infected pneumonia in Wuhan, China. Jama 2020;
32. Hui DS, I Azhar E, Madani TA, Ntoumi F, Kock R, Dar O, et al. The continuing 2019-nCoV epidemic threat of novel coronaviruses to global health—The latest 2019 novel coronavirus outbreak in Wuhan, China. Int J Infect Dis 2020; 91: 264–6.
33. Nishiura H, Linton NM, Akhmetzhanov AR. Initial cluster of novel coronavirus (2019-nCoV) infections in Wuhan, China is consistent with substantial human-to- human transmission. Multidisciplinary Digital Publishing Institute 2020;
34. Yang Y. et al. Epidemiological and clinical features of the 2019 novel coronavirus outbreak in China. medRxiv 2020a;
35. Zhang Y, Xu JM. Medical diagnosis and treatment strategies for malignant tumors of the digestive system during the outbreak of novel coronavirus pneumonia. Zhonghua Zhong Liu Za Zhi 2020; 42 (0), E005.
36. Lei J, et al. CT imaging of the 2019 novel coronavirus (2019-nCoV) pneumonia.
Radiol 2020a; 295 (1), 18.
37. Fan C, et al. ACE2 Expression in Kidney and Testis May Cause Kidney and Testis Damage After 2019-nCoV Infection. medRxiv 2020.02.12.20022418.
38. Lu G, Wang Q, Gao GF. Bat-to-human: spike features determining ‘host jump’ of coronaviruses SARS-CoV, MERS-CoV, and beyond. Trends Microbiol 2015; 23;
468–478.
39. Li F. Structure, function, and evolution of coronavirus spike proteins. Annu Rev Virol 2016; 3: 237–261.
40. Song HD, Tu CC, Zhang GW, Wang SY, Zheng K, Lei LC, et al. Cross-host evolution of severe acute respiratory syndrome coronavirus in palm civet and human.
Proc Natl Acad Sci 2005; 102: 2430–2435.
41. Woo PC, Lau SK, Huang Y, Yuen KY. Coronavirus diversity, phylogeny and interspecies jumping. Exp Biol Med 2009; 234: 1117–1127.
42. Malik YS, Sircar S, Bhat S, Sharun K, Dhama K, Dadar M, et al. Emerging novel coronavirus (2019-nCoV)—current scenario, evolutionary perspective based on genome analysis and recent developments. Vet Q 2020; 40: 68–76. doi: 10.1080/
01652176.2020.1727993.
43. Chu DKW, Pan Y, Cheng SMS, Hui KPY, Krishnan P, Liu Y, et al. Molecular diagnosis of a novel coronavirus (2019-nCoV) causing an outbreak of pneumonia.
Clin Chem 2020 Jan 31 [Epub ahead of print]. doi: 10.1093/clinchem/hvaa029 . 44. Salata C, Calistri A, Parolin C, Palù G. Coronaviruses: a paradigm of new emerging
zoonotic diseases. Pathogens and Disease 2020; 77.
45. Sheahan T, Rockx B, Donaldson E, Corti D, Baric R. Pathways of crossspecies transmission of synthetically reconstructed zoonotic severe acute respiratory syndrome coronavirus. J Virol 2008; 82: 8721–8732.
46. Xu L, Zhang Y, Liu Y, Chen Z, Deng H, Ma Z, et al. Angiotensin-converting enzyme 2 (ACE2) from raccoon dog can serve as an efficient receptor for the spike protein of severe acute respiratory syndrome coronavirus. J Gen Virol 2009; 90: 2695–2703.
47. Song F, Shi N, Shan F, Zhang Z, Shen J, Lu H, et al. Emerging coronavirus 2019- nCoV pneumonia. Radiology 2020 Feb 6 [Epub ahead of print]. doi: 10.1148/
radiol.2020200274.
48. Kim JY, Choe PG, Oh Y, Oh KJ, Kim J, Park SJ, et al. The first case of 2019 novel coronavirus pneumonia imported into Korea from Wuhan, China: implication for infection prevention and control measures. J Korean Med Sci 2020; 35: e61. doi:
10.3346/jkms.2020.35.e61 .
49. Carlos WG, Cruz CSD, Cao B, Pasnick S, Jamil S. Novel Wuhan (2019-nCoV) coronavirus. Am J Respir Crit Care Med 2020; 201: 7–8.
50. Lauer SA, Grantz KH, Bi Q, Jones FK, Zheng Q, Meredith H, et al. The incubation period of coronavirus disease 2019 (COVID-19) from publicly reported confirmed cases: estimation and application. Ann Intern Med 2020 Mar 10 [Epub ahead of print]. doi: 10.7326/m20-0504.
51. Sattar DS. Human pathogenic coronaviruses: understanding their environmental survival for better infection prevention and control. 2020.
52. Jin YH, Cai L, Cheng ZS, Cheng H, Deng T, Fan YP. A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version). Mil Med Res 2020; 7: 4.
53. WHO. https://www.who.int/emergencies/diseases/novel-coronavirus-2019.2020.
