key: cord-325452-2sywbgje
authors: Sun, Pengfei; Lu, Xiaosheng; Xu, Chao; Sun, Wenjuan; Pan, Bo
title: Understanding of COVID‐19 based on current evidence
date: 2020-03-05
journal: J Med Virol
DOI: 10.1002/jmv.25722
sha: 
doc_id: 325452
cord_uid: 2sywbgje

Since December 2019, a series of unexplained pneumonia cases have been reported in Wuhan, China. On 12 January 2020, the World Health Organization (WHO) temporarily named this new virus as the 2019 novel coronavirus (2019‐nCoV). On 11 February 2020, the WHO officially named the disease caused by the 2019‐nCoV as coronavirus disease (COVID‐19). The COVID‐19 epidemic is spreading all over the world, especially in China. Based on the published evidence, we systematically discuss the characteristics of COVID‐19 in the hope of providing a reference for future studies and help for the prevention and control of the COVID‐19 epidemic.

SARS-CoV-2 is a coronavirus and belongs to the β-coronavirus cluster.

COVID-19 is the third known zoonotic coronavirus disease after SARS and the Middle East respiratory syndrome (MERS). SARS-CoV and MERS-CoV also belong to the β-coronavirus cluster. 3 Zhu et al 4 confirmed that SARS-CoV-2 was a new β-coronavirus belonging to the subgenus botulinum of Coronaviridae. According to the current data, 5 the early COVID-19 cases were related to the Huanan seafood market, and the possibility of human-to-human transmissions could not be ruled out. The WHO report claimed that the SARS-CoV-2 could be detected in the environmental samples collected from the seafood market, but it

has not yet been determined if a specific animal species carries the SARS-CoV-2. A study by Ji et al 6 showed that the SARS-CoV-2 was a chimeric virus between a bat coronavirus and a coronavirus of unknown origin. By comparing with other animals, they found that snakes are the most likely wildlife repository for the SARS-CoV-2. 6 The research by and SARS-CoV was 79.5%. They also found that the SARS-CoV-2 had high homology with bat coronaviruses. Therefore, the current evidence strongly supports that the SARS-CoV-2 was derived from bats, although the intermediate hosts of SARS-CoV-2 remain to be determined.

A study by Wang et al 12 In the absence of effective treatments, the best way to deal with the SARS-CoV-2 epidemic is to control the sources of infection. 9 According to the official Chinese data, the case fatality rate among the SARS-CoV-2-infected patients was much lower than that of SARS and MERS. 2 In response to the COVID-19 epidemic, we believe that the focus of future studies will still be on the development of COVID-19 vaccines and effective drugs to treat COVID-19. These studies will help further reduce the case fatality and transmission rates among SARS-CoV-2-infected patients. Moreover, super-spreaders were reported during the SARS and MERS epidemics. 21 Although the transmission rate for SARS-CoV-2 patents is about 2.2 at present, the number of cases inside and outside Wuhan is increasing rapidly. With the progress of diagnostic technology, potential super-spreaders may be discovered in the future. In the prevention of the spread of SARS-CoV-2, asymptomatic spreaders also need to be focused. 22 In addition, Sheng et al 23 found that viral infections can increase the risk of pulmonary fibrosis. Therefore, pulmonary fibrosis may be one of the severe complications after patients recover from 2019-nCoV infections. The prevention of pulmonary fibrosis in patients recovered from 2019-nCoV infections is an issue that urgently needs to be addressed.

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Understanding of COVID-19 based on current evidence

The authors acknowledge TopEdit LLC for linguistic editing and proofreading during the preparation of this manuscript.

The authors declare that there are no conflict of interests.

BP and PS had the idea for and designed the study and take responsibility for the integrity of the data and the accuracy of the data analysis. PS and XL contributed to the writing of the report. BP contributed to the critical revision of the report. CX and WS contributed to the statistical analysis. All authors contributed to data acquisition, data analysis, or data interpretation, and reviewed and approved the final version.

http://orcid.org/0000-0001-8900-8479