ISSN 2500-2236
DOI-prefix: 10.18527/2500-2236

What do we know today about the new coronavirus isolated in China?

Publish date: 30.01.2020

In December 2019, several patients associated with the wholesale seafood market in Wuhan, China, were hospitalized with severe pneumonia of unknown etiology. On December 31, 2019, the World Health Organization (WHO) was notified of several cases of pneumonia in Wuhan, Hubei Province (China) (https://www.who.int/emergencies/diseases/novel-coronavirus-2019).

On December 27, 2019, three adult patients with severe pneumonia (one woman 49 years old and two men aged 61 and 32 years) were taken to a hospital in Wuhan. The diagnosis of pneumonia was made on the basis of computer tomography (CT) data. On December 30, 2019, samples of bronchoalveolar lavage were taken from these patients in the Wuhan Jinting Hospital. Previously unknown virus of Betacoronavirus genus belonging to the Coronaviridae family [1] was discovered in all three samples. Therefore, the new coronavirus infection was confirmed in these patients.

Coronaviruses (CoVs) are widespread among mammals and birds and cause respiratory, intestinal, and neurological diseases, as well as liver diseases [2]. Six types of Coronaviridae family cause disease in humans [3]. Two CoVs - Severe Acute Respiratory Syndrome (SARS-CoV) and Middle Eastern Respiratory Syndrome (MERS-CoV) are known to cause fatal illnesses. These viruses have a zoonotic nature and caused acute respiratory distress syndrome in patients in 2002 and 2003 in Guangdong China [4] and in 2012 in the Middle East [4].

The new virus was named 2019-nCoV, and the disease caused by this CoV - new coronavirus pneumonia (NCIP). The 2019-nCoV is different from MERS-CoV and SARS-CoV and represents the seventh member of the Coronaviridae family that infects humans.

Viral particles were isolated from the clinical samples of patients on the primary epithelial cells of human respiratory tract. On the electron micrograph, the 2019- nCoVs are depictured mainly as spherical particles with a diameter of 60 to 140 nm. Particles of the virus have characteristic 9 to 12 nm spikes, which give the virions the appearance of a solar corona that consequently determines their name.

The complete genome sequences of the three new coronaviruses have been identified and deposited to the international GASAID database (BetaCoV / Wuhan / IVDC-HB-01/2019). Although 2019-nCoV is similar to some viruses of Betacoronavirus genus (86.9% identity with bat-SL-CoVZC45, MG772933.1) found in bats, it differs from SARS-CoV and MERS-CoV. Phylogenetic analysis showed that three 2019-nCoVs from Wuhan, together with two similar to SARS strains (ZC45 and ZXC21) isolated from bats, form a separate clade within the genus Betacoronavirus of the Coronaviridae family.

As of January 24, 2020, at least 830 cases of 2019-nCoV diseases were diagnosed in nine countries: China, Thailand, Japan, South Korea, Singapore, Vietnam, Taiwan, Nepal, and the United States. Twenty-six deaths occurred, mainly in patients who had serious basic diseases [5].

Currently, epidemiological studies with the goal to determine how quickly and easily the virus can be transmitted from person to person are critical. These studies are necessary in order to develop a strategy to stop the spread of infection caused by 2019-nCoV.

The New England Journal of Medicine announced that all articles about the outbreak of the new coronavirus published in this journal are available on the journal's website (https://www.nejm.org/coronavirus) in the public domain from the day of publication, where a special webpage has been created for all articles about nCoV - www.NEJM.org/coronavirus

The Boston Children's Hospital's HealthMap team keeps track of public reports of confirmed and suspicious 2019-nCoV cases worldwide. The map is permanently updated: http://www.healthmap.org/ncov2019/

REFERENCES

1. 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. Epub 2020/01/25. doi: 10.1056/NEJMoa2001017. PubMed PMID: 31978945.

2. Weiss SR, Leibowitz JL. Coronavirus pathogenesis. Adv Virus Res. 2011;81, 85-164. Epub 2011/11/19. doi: 10.1016/B978-0-12-385885-6.00009-2. PubMed PMID: 22094080.

3. Cui J, Li F, Shi ZL. Origin and evolution of pathogenic coronaviruses. Nat Rev Microbiol. 2019;17(3), 181-92. Epub 2018/12/12. doi: 10.1038/s41579-018-0118-9. PubMed PMID: 30531947.

4. Zhong NS, Zheng BJ, Li YM, Poon, Xie ZH, Chan KH, et al. Epidemiology and cause of severe acute respiratory syndrome (SARS) in Guangdong, People's Republic of China, in February, 2003. Lancet. 2003;362(9393), 1353-8. Epub 2003/10/31. doi: 10.1016/s0140-6736(03)14630-2. PubMed PMID: 14585636.

5. Munster VJ, Koopmans M, van Doremalen N, van Riel D, de Wit E. A Novel Coronavirus Emerging in China - Key Questions for Impact Assessment. N Engl J Med. 2020. Epub 2020/01/25. doi: 10.1056/NEJMp2000929. PubMed PMID: 31978293.