Update on the SARS-CoV-2 (COVID-19) Outbreak: A Global Pandemic Challenge

The 2019 novel coronavirus (previously 2019-nCoV) or coronavirus infectious disease 2019 (COVID-19) outbreak has been summarized as on March 29, 2020. COVID-19 is a highly transmittable and pathogenic viral infection caused by severe acute respiratory syndrome coronavirus 2 (SERS-CoV-2). The disease was first seen during an outbreak in Wuhan, China and continuous spreading from human to human around the sphere. The disease is uncontrolled and increasing the death toll through. The world is facing a global challenge to protect human lives caused by coronavirus outbreak. The number of infected patients is increasing day by day due to COVID-19 as a pandemic. The world health organization (WHO) has declared global public health emergency on January 30, 2020. The disease has been spread around 201 countries with total confirmed cases 634835 and death cases 29891 as on March 29, 2020. The goal of this review to summaries and update the clinical/medical features and suggestions for diagnosis of the COVID-19 as a pandemic. The discussion of the various therapeutic algorithms, risk, prevention and control based on the latest reports has been provided.

with an ID NC_045512 [3]. The rapid transfer of disease from human to human has been confirmed. No availability of clinically approved vaccine for COVID-19 is found till the date. However, the clinical trials are sustained to few antiviral drugs development. CoVs is divided into four classes: alpha-coronavirus, beta-coronavirus, gamma-coronavirus and delta-coronavirus [4]. Six human coronaviruses (HCoVs) have been noted, including the alpha-CoVs HCoVs-NL63 (Alphacoronavirus lineage 1b member) and HCoVs-229E coronavirus (HCoVs) and transmission is increasing periodically in humans. It may also affect the gastrointestinal system including heart, liver, kidney, and central nervous system prominent to multiple organ failure [5,6]. Baig et al. have revealed tissue distribution, hostvirus interaction and neurotropic mechanism for COVID-19 [7]. They have shown that similar to SARS-CoV, COVID-19 virus exploits the angiotensin-converting enzyme 2 (ACE2) receptor to gain entry inside the cells. The spike protein of COVID-19 comprises a 3D structure in the receptor-binding domain (RBD) region to maintain the van der Waals forces [8]. The life cycle of COVID-19 in host cells can be realized when S protein binds to the cellular receptor ACE2 and initiates life cycle [9].

(a). Objective of the review
Due to declaration of public health emergency of international concern (PHEIC) by WHO as on January 30, 2020 for 2019-nCoV or COVID-19 officially named severe acute respiratory syndrome coronavirus 2 (SARC-CoV-2), the present review summarizes, recent update and discuss the clinical aspects, current condition, risk, challenges and preventions. An urgent update is required on the effect of COVID-19 as a global pandemic on human health system. Detailed emphasize has been considered for outbreak of COVID-19 in India.

(b). Method
Most recent literatures were reviewed for COVID-19 a global pandemic at the time of writing (March 29, 2020). A literature search was carried out via web of science, PubMed and other sources available from the internet. Search word comprises "COVID-19" or Coronavirus or "2019-nCoV" or "Severe Acute Respiratory Syndrome (SARS-CoV)" or "Middle East Respiratory Syndrome (MERS-CoV)". The nature of this review is based on literature search and hence no ethical approval was required. circling back around the globe [11]. The WHO risk assessment on the global level is very high.

Global response caused by COVID-19
The spread of COVID-19 as a global pandemic has been seen over the many countries (201). Graphic of the topographical spread of confirmed COVID-19 disease has been given in the Figure 2. In order to help countries to stop the spread, interruption of transmission, detection, and manage the COVID-19 disease, the United Nations Foundation (NRF) and the Swiss Philanthropy Foundation (SPF) have generated the solidarity fund to sustenance WHO and partners in a substantial asset [12]. The fund will be used by the WHO and partners to support countries rendering to the COVID-19 strategic awareness and response plan. A large number of studies as a solidarity trail in many countries has been started to compare different treatments. this epidemic, health workers, scientist, governments and the public need to unite altogether [14]. Spread of disease can be divided into various stages of pandemic COVID-19 transmission (Table 1). Stage 1 is slow imported cases, stage 2 is local transmission and the stage 3 is critical due to the community transmission. Also, the other stages (4-6) are worst and required proper attention from government. China (82356), Italy (92472), Spain (72248), Germany (52547) and United States of America (103321) has already crossed the stage 3 (all have crossed the confirmed cases above than 50000) and the condition was very critical due to disease with no clear end point. The infected human can possibly spread the COVID-19 even before they become symptomatic [15].

Stage 1
These are the imported cases, patient has travelled to pandemic COVID-19 affected foreign continent to other continent in the world.

Stage 2
These are the local transmission. The cases has come to contact with the patients through local transmission, who have a travel history. The person most probable got infected and passed to others. Contact tracing can be used to stop the spread of disease via breaking of chain of transmission.

Stage 3
These are the community transmission. In this stage, a large areas get affected and hence uncontrolled mass level transmission is possible. There may be starting of a chain reaction and huge number of patients infected with COVID-19 is started.

Stage 4
These are the epidemic. This stage of the disease is worst. Rapid burst of the disease with no clear end point.

Stage 5
The entire area is under quarantine. An urgent need to stop the spread of pandemic as much as possible is required.

Stage 6
Most of the businesses viz. restaurants, shopping centers and all kind of shops are closed. The instructions of the government strictly used to follow by the persons till the situation is under control.

COVID-19 pandemic effect in India
The population of India is around 1.3 billion. India is the second largest populated country in the world after China. The discussion about India is very important due to the high population and supposed to be substantially affected by the COVID-19 pandemic.
The current situation of India is 'total lockdown' in an attempt to slow the spread of the  On the basis of the Indian national data the mortality rate for outbreak of COVID-19 is 3.0% as on March 29, 2020. The consecutive incidence of COVID-19 pandemic (a) infections and (b) death cases in India appears in January 30, 2020 to March 29, 2020 has been shown in the

Transmission and mortality
In   [18]. Recent information specifies that COVID-19 is more transmissible than SARS-CoV [19]. A report shows the stability of COVID-19 in the aerosols, plastic, stainless steel, copper, and cardboard are 3, 72, 48, 4 and 24 hours, respectively at 40% relative humidity and 21-23°C temperature [20]. A detailed study personto-person transmission of COVID-19 occurred between two people with prolonged, unprotected exposure was reported in USA [21]. Human to human transmission is possible through droplets or direct contact. Mortality rate depends on study and population and hence altered in various reports. COVID-19 can extant asymptomatic carrier state, acute respiratory disease (ARD) and pneumonia [22].  China is trying first vaccine trial after sharing of genetic sequence of the virus. Recently, the first human trial of a vaccine to defend against COVID-19 pandemic has underway in the US [25]. Many clinical trials have been led in China to examine, the ability and safety of Chloroquine and hydroxychloroquine to treat the infected patients from the COVID-19 [26].
A worldwide arms race for the development of vaccine is going on. The treatment of COVID-19 infection is symptomatic and inhaled interferon-alpha (antiviral drug) and oral lopinavir or ritonavir has been suggested as antiviral treatment by the National Health Committee of the People's Republic of China [24]. It was observed that Chloroquine itself and combination with antiretroviral agents can be effective for human immunodeficiency virus (HIV). Recent report based on in-vitro study shows, that remdesivir and chloroquine were very effective in the control of COVID-19 [27,28]. Moreover, there are some other potential drug such as nucleoside analogues remdesivir, umifenovir (Arbidol Ⓡ ), chloroquine, neuraminidase inhibitors, DNA synthesis inhibitors (tenofovir disoproxil and lamivudine), and Chinese traditional medicines (ShuFeng JieDu or Lianhua Qingwen capsules), have been proposed by the researchers [27,29]. The COVID-19 can be detected in the gastrointestinal tract, urine and saliva [30]. Therefore, the mode of transmission should be reset to prevent the spread of disease.
In Covid-19, the absence of fever is more recurrent than in SARS (about 1%) and MERS infection (about 2%) [31]. There may be possible of the patients to be lost if the investigation case definition concentrated on fever exposure. Bioinformatics studies has been carried to design of a synthetic vaccine and a preventative peptidomimetic antagonist against COVID-19 [32]. CoVs-related biologics includes therapeutic antibodies, cytokines, and nucleic acid-based therapies targeting virus gene expression as well as various types of vaccines has been discussed by Liu et al. [33]. Teicoplanin as a potential treatment for patients with this virus has been suggested [34]. A recent report tells that inflammatory cytokine storm was very common in patients with severe COVID-19 in China [35]. Travel history rather than chest radiography is of vital importance for initial detection, quarantine and isolation of COVID-19 infected patients is important [36]. The CoVs can live for three days on the plastic and steel enabling increment in the infection through surface contacts. The viability of virus in the air is an additional threat [20]. People should avoid close contact with people suffering from acute respiratory infections, cover coughs and sneezes, wash hand frequently, follow healthcare facilities, virus infection prevention strategy as per the government rules and control practices are recommended in hospital [37].

(b) Challenge and safety as global health management
The COVID-19 outbreak has not been well controlled and needs close care.  peoples are in quarantine, which may raise an issue of strong human health concern.

Acknowledgments
The Author is thankful to CBCS, University of Allahabad.

Data statement
The data in this review is not sensitive in nature and is available in the public domain. The data is therefore accessible and not of a confidential nature.

Competing interests:
The author declares no conflict of interests.