SARS-CoV-2Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)is the virus strain that causes coronavirus disease 2019 (COVID-19), a respiratory illness. Colloquially known as the coronavirus, it was previously referred to by its provisional name 2019 novel coronavirus (2019-nCoV).as described by the National Institutes of Health, it is the successor to SARS-CoV-1.sARS-CoV-2 is a positive-sense single-stranded RNA virus.It is contagious in humans, and the World Health Organization (WHO) has designated the ongoing pandemic of COVID-19 a Public Health Emergency of International Concern.
Taxonomically, SARS-CoV-2 is a strain of severe acute respiratory syndrome-related coronavirus (SARSr-CoV).it is believed to have zoonotic origins and has close genetic similarity to bat coronaviruses, suggesting it emerged from a bat-borne virus. There is no evidence yet to link an intermediate animal reservoir, such as a pangolin, to its introduction to humans. The virus shows little genetic diversity, indicating that the spillover event introducing SARS-CoV-2 to humans is likely to have occurred in late 2019.
Epidemiological studies estimate each infection results in 1.4 to 3.9 new ones when no members of the community are immune and no preventive measures taken. The virus primarily spreads between people through close contact and via respiratory droplets produced from coughs or sneezes. It mainly enters human cells by binding to the receptor angiotensin converting enzyme 2 (ACE2).
Human-to-human transmission of SARS-CoV-2 was confirmed on 20 January 2020, during the COVID-19 pandemic. Transmission occurs primarily via respiratory droplets from coughs and sneezes within a range of about 1.8 metres (6 ft). Indirect contact via contaminated surfaces is another possible cause of infection. Preliminary research indicates that the virus may remain viable on plastic and steel for up to three days, but does not survive on cardboard for more than one day or on copper for more than four hours; the virus is inactivated by soap, which destabilises its lipid bilayer. Viral RNA has also been found in stool samples from infected individuals.
The degree to which the virus is infectious during the incubation period is uncertain, but research has indicated that the pharynx reaches peak viral load approximately four days after infection or the first week of symptoms, and declines after. On 1 February 2020, the World Health Organization (WHO) indicated that "transmission from asymptomatic cases is likely not a major driver of transmission".However, an epidemiological model of the beginning of the outbreak in China suggested that "pre-symptomatic shedding may be typical among documented infections" and that subclinical infections may have been the source of a majority of infections. Similarly, a study of ninety-four patients hospitalized in January and February 2020 estimated patients shed the greatest amount of virus two to three days before symptoms appear and that "a substantial proportion of transmission probably occurred before first symptoms in the index case".
There is some evidence of human-to-animal transmission of SARS-CoV-2, including examples in felids. Some institutions have advised those infected with SARS-CoV-2 to restrict contact with animals.
Coronaviruses (CoVs), a large family of single-stranded RNA viruses, can infect animals and also humans, causing respiratory, gastrointestinal, hepatic, and neurologic diseases (Weiss and Leibowitz, 2013). As the largest known RNA viruses, CoVs are further divided into four genera: alpha-coronavirus, beta- coronavirus, gamma-coronavirus and delta-coronavirus (Yang and Leibowitz, 2015). To date, there have been six human coronaviruses (HCoVs) identified, including the alpha-CoVs HCoVs-NL63 and HCoVs-229E and the beta-CoVs HCoVs-OC43, HCoVs-HKU1, severe acute respiratory syndrome-CoV (SARS-CoV) (Drosten et al., 2020), and Middle East respiratory syndrome-CoV (MERS-CoV) (Zaki et al., 2012). New coronaviruses appear to emerge periodically in humans, mainly due to the high prevalence and wide distribution of coronaviruses, the large genetic diversity and frequent recombination of their genomes, and the increase of human-animal interface activities (Cui et al., 2019, Zhu et al., 2019).
In late December 2019, a number of local health authorities reported clusters of patients with pneumonia of unknown cause, which were epidemiologically linked to a seafood market in Wuhan, Hubei Province, China (Zhu et al., 2019) The pathogen, a novel coronavirus (SARS-CoV-2), was identified by local hospitals using a surveillance mechanism for “pneumonia of unknown etiology” that was established in the wake of the 2003 SARS outbreak with the aim of allowing timely identification of novel pathogens (Li et al., 2020a, Zhu et al., 2019). On 30 January 2020, the World Health Organization (WHO) declared that CoVID-19 is a “public-health emergency of international concern” (Li et al., 2020b). The pandemic is escalating rapidly. We searched the associated literature on CoVID-19 to summarize the epidemiology, clinical characteristics, diagnosis and treatments, and preventions of the infection of SARS-CoV-
Scope of the CoVID-19 infection outbreak
Since December 2019, multiple cases with unexplainable pneumonia were successively reported in some hospitals in Wuhan city. The cases had a history of exposure to a large seafood market in Wuhan city, Hubei province, China. It has been confirmed to be an acute respiratory infection caused by a novel coronavirus. So far, this disease has rapidly spread from Wuhan to China’s other areas, and 66 countries. And then, clustered cases and confirmed cases without a history of travel to Wuhan emerged as the advancement of this disease (Jin et al., 2020). In addition, confirmed cases without clear exposure to the seafood market of Wuhan have been spread in many foreign countries (Stoecklin et al., 2020).
According to National Health Commission of the People`s Republic of China, as of 24:00 on March 2, 2020, a total of 80, 302 CoVID-19 cases in China have been confirmed in 31 provinces (autonomous regions and municipalities), and Xinjiang Production and Construction Crops, including Hong Kong, Macao, and Taiwan, including 2947 (3.66%) deaths. At present, there are 30,095 confirmed cases (6806 severe cases), 47,260 (58.85%) discharged cases, and 587 suspected cases recorded. It is worth mentioning that up to now, Tibet and Qinghai provinces have no new coronavirus infected patients (National-Health-Commission-of-the-People’s-Republic-of-China, 2020). As of 11 February, a total of 1715 medical workers had been infected, of which 5 had died, with a crude case fatality rate of 0.3%. The number of confirmed cases has surpassed those of SARS in 2003.
Internationally, confirmed cases have been reported in 66 countries and 6 continents and aboard the Diamond Princess. Outside of China, a total of 10,415 cases of CoVID-19 have been reported from 66 countries, with 168 deaths. The epidemics in the Republic of Korea, Italy, Iran and Japan have been became the greatest concern of WHO (WHO and WHO, 2020). According to the European Centre for Disease Prevention and Control (ECDC) (European-Centre-for-Disease-Prevention-and-Control, 2020), regarding the latest daily risk assessment on COVID-19, March 2, the ECDC has now considered the risk moderate to high level. The case fatality rate of the currently reported cases in China is less than 4%, which implies that so far, this novel coronavirus does not seem to cause the high fatality rates previously observed for SARS-CoV and MERS-CoV, 10% and 37%, respectively (Chaolin et al., 2020). According to the latest data, a total of 36167 cases were reported in Hubei, China, which gives a cumulative attack rate (CAA) of 0.11% (the permanent resident population of Hubei is about 59, 170,000). However, when compared to the influenza virus of pH1N1, which shared the same transmission route but had a 50 times higher CAA, these data showed the importance of the intense quarantine and social distancing measures the Hubei government has taken.
the Editor — Since the first reports of novel pneumonia (COVID-19) in Wuhan, Hubei province, China1,2, there has been considerable discussion on the origin of the causative virus, SARS-CoV-23 (also referred to as HCoV-19)4. Infections with SARS-CoV-2 are now widespread, and as of 11 March 2020, 121,564 cases have been confirmed in more than 110 countries, with 4,373 deaths5.
SARS-CoV-2 is the seventh coronavirus known to infect humans; SARS-CoV, MERS-CoV and SARS-CoV-2 can cause severe disease, whereas HKU1, NL63, OC43 and 229E are associated with mild symptoms6. Here we review what can be deduced about the origin of SARS-CoV-2 from comparative analysis of genomic data. We offer a perspective on the notable features of the SARS-CoV-2 genome and discuss scenarios by which they could have arisen. Our analyses clearly show that SARS-CoV-2 is not a laboratory construct or a purposefully manipulated virus.
According to my dataset observed, I was able to understand the impact of the virus on Africa Economy and masses were suffering from hunger, lack of money to meet their daily needs. I would recommend the government to provide palliatives to the vulnerable and affected masses to stay at home because the disease is deadly and present n vaccine to cure it for now.