DYNAMICS, ROUTES AND MECHANISMS OF TRANSMISSION IN COVID-19: A REVIEW

Xingxuan Cai^{1, 2}, JunqingJia¹, Changfei Wang³, Xiaofei Zhang¹, Jiaojiao Lin⁴, Yaoyong Wang^{1, *}

¹Department of Respiratory and Critical Care Medicine, Fenyang Hospital of Shanxi Province, Fenyang, China - ²Department of Graduate School, Shanxi Medical University, TaiYuan, China - ³Department of Information, Fenyang Hospital of Shanxi Province, Fenyang, China - ⁴Department of Internal medicine, the SecondAffiliated Hospital of FujianMedical University, Quanzhou, China

Introduction: The ongoing pandemic of novel coronavirus disease 2019(COVID-19) has affected many people from all over the world, and has seriously threaten public health and econonmy, since December 2019. Unfortunately, to date, no registered specific antiviral agents and vaccines make difficult to treat contagious patients and protect susceptible people, resulting in cutting off transmission routes is indispensable prevention and control measure. Consequently, understanding the underlying exposure routes is incredibly important for containing the pandemic.

Material and methods: The review of the literature was performed by search engines, such as PubMed, Scopus, WanFang Data, CNKI, Google and Web of Science.

Results: Patients with COVID-19 are contagious started from 2.3 days before symptoms onset, and who could still to transmit SARS-CoV-2 after symptoms onset or discharge. Airborne coronavirus and contact coronavirus are main patterns in the spread of SARS-CoV-2. Fecal-oral transmission, blood transmission, sexual transmission, extracellular fluid(e.g., urine) transmission and mother-to-child transmission are all contributing to exposure to SARS-CoV-2. In addition, SARS-CoV-2 also spread from animals to animals, animals to humans and humans to animals.

Conclusion: SARS-CoV-2 could not only spread between animals and humans, and circulating in animals. We should be aware of transmission dynamics and methods of transmission are conducive to prevent further spreading.