The Start of New Year, The Start of Novel 2019-novel Coronavirus (2019-nCoV)
On 30 Jan 2020, World Health Organization (WHO) had declared Public Health Emergency of International Concern over the global outbreak of coronavirus (CoV) named as 2019-nCoV infection with scaring the further spreading of this disease to other countries which have weaker health systems 1. Till now, the confirmed cases have been risen to about 17,000 cases and death tolls passed 360 2.
Biology of Coronavirus.
Belonging to the family of Coronaviridae, CoV consists of four genera which include Alphacoronavirus, Betacoronavirus, Gammacoronavirus and Deltacoronavirus. It possessed single-stranded, positive-sense RNA genome which is about 30 kb in length 3. Two-third of the CoV genome is responsible for encoding non-structural proteins. In the meanwhile, one-third of the genome encodes for the structural proteins such as spike (S), membrane (M), envelope (E) and nucleocapsid (N) proteins. Besides shaping the virus, these structural proteins are responsible for virion assembly and pathogenesis of CoV 4.
Previously, two betacoronavirus-related outbreaks happened in last two decades known as SARS and MERS which are affected by SARS-CoV and MERS-CoV, respectively. Sequence analysis revealed that the newly emerged 2019-nCoV shares the genome structure which is belonging to the cluster of betacoronavirus which is found in infected animals and humans 4. By de novo assembly and targeted PCR, Zhou et al. revealed that the 2019-nCoV genome shares the sequence similarity of 79.5% to SARS-CoV 5. Furthermore, Simplot analysis exhibited that 2019-nCoV had high genome sequence similarity of about 96% with bat CoV. Besides, the phylogenetic tree of CoV also showed that 2019-nCoV is more closely related to bat-SL-CoV ZX45 and bat-SL-CoV ZXC21 and more distantly related to SARS-CoV 6.
The spreading of 2019-nCoV
In December 2019, the outbreak of 201-nCoV happened at the Wuhan Huanan Seafood Wholesale Market. However, fish is not the source of contamination as CoV in fish belongs to different genera and different host ranges 4. Further investigation revealed that the other livestock such as wild animals sold at the market is the culprit of the spread on 2019-nCoV from animal to human. This livestock was suspected to be an intermediate host between bats and humans as bat CoV shares the highest genome sequence similarity with 2019-nCoV 6. Moreover, this zoonotic disease can be spread via the route of human-to-human transmission. Chan et al. showed that the six family members who are 2019-nCoV positive never visited Wuhan seafood market and one of them did not travel to Wuhan. Besides, the human-to-human transmission of 2019-nCoV to Europe happened in Germany in which a man was infected by a China colleague, signifying the potential threat of this deadly virus via human-to-human transmission internationally 7. Currently, this infection has been transmitted to South-East Asian countries, Australia, Japan, Finland, Italy, Canada, India and so on.
Common symptom of infection, treatment and prevention
The common symptoms of this deadly infection include fever, cough, sneezing, sore throat and difficulty in breathing. 8,9. Based on the Centers for Disease and Prevention Control (CDC), the symptoms of 2019-nCoV may appear ranges from two until 14 days after the exposure 9.
Currently, there is no specific antiviral therapy or any vaccines available for the treatment of 2019-nCoV. Scientists are racing to develop treatments against this deadly virus. A research team in Hong Kong led by Prof Yuen Kwok-Yung announced that they isolated the virus from the patient and developed the vaccine. They also reported that time is needed for testing on animals and running clinical trials before releasing into the market 10. Furthermore, Dr Julian Druce, Dr Mike Catton and their research team from The Peter Doherty Institute for Infection and Immunity, Australia successfully isolated and grew the CoV in cell culture. With the cultured virus, this allows the researchers to develop novel treatments against this deadly infection and the diagnostic methods by detecting specific antibodies specific to 2019-nCoV 11.
Good personal hygiene practices such as frequent hand wash with sanitizers and wear personal protective equipment such as surgical masks and N95 respirators are necessary to avoid contact with 2019-nCoV 8. Besides, residents are encouraged to avoid visiting crowded places to prevent contact with 2019-nCoV 4.
Conclusion
In short, the sudden emerging of 2019-nCoV has become a global health threat. Scientists are racing against time with the hope of understanding the biology of this novel virus and developing the vaccine. In the meanwhile, people should always be alert about this deadly infection and practising preventive measurements regularly.
Let’s hope that 2019-nCoV infection will be eradicated soon!
Reference
1. Lovelace Jr. B, Feuer W. WHO declares China coronavirus that’s killed more than 200 a global health emergency. CNBC Health And Science. https://www.cnbc.com/2020/01/30/who-declares-china-coronavirus-a-global-health-emergency.html. Published 2020. Accessed February 3, 2020.
2. Ramzy A, Buckley C, May T, et al. Coronavirus Live Updates: Stocks Sink as Markets Open in China. The New York Times. https://www.nytimes.com/2020/02/02/world/asia/china-coronavirus.html. Published 2020. Accessed February 3, 2020.
3. Chan JF-W, Yuan S, Kok K-H, 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. February 2020. doi:10.1016/S0140-6736(20)30154-9
4. Chen Y, Liu Q, Guo D. Emerging coronaviruses: genome structure, replication, and pathogenesis. J Med Virol. 2020;n/a(n/a). doi:10.1002/jmv.25681
5. Zhou P, Yang X-L, Wang X-G, et al. Discovery of a novel coronavirus associated with the recent pneumonia outbreak in humans and its potential bat origin. bioRxiv. January 2020:2020.01.22.914952. doi:10.1101/2020.01.22.914952
6. Lu R, Zhao X, Li J, et al. Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding. Lancet. February 2020. doi:10.1016/S0140-6736(20)30251-8
7. Boseley S. Germany confirms first human coronavirus transmission in Europe. The Guardian. https://www.theguardian.com/science/2020/jan/28/germany-confirms-first-human-coronavirus-transmission-in-europe. Published 2020. Accessed January 30, 2020.
8. Huang C, Wang Y, Li X, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet. February 2020. doi:10.1016/S0140-6736(20)30183-5
9. 2019 Novel Coronavirus Symptoms & Complications. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/about/symptoms.html. Published 2020. Accessed February 3, 2020.
10. Cheung E. China Coronavirus: Hong Kong Researchers Have Already Developed Vaccine But Need Time To Test It, Expert Reveals. South China Morning Post.
11. Akst J. Australian Lab Cultures New Coronavirus as Infections Climb. The Scientist. https://www.the-scientist.com/news-opinion/australian-lab-cultures-new-coronavirus-as-infections-climb-67031. Published 2020. Accessed January 31, 2020.