Review of the risk factors for SARS-CoV-2 transmission

Table 4 Unanswered questions about severe acute respiratory syndrome coronavirus 2

Unanswered questions about SARS-CoV-2
Where does SARS-CoV-2 really originated from and how does it affect humans?
Will the spread of SARS-CoV-2 be a seasonal outbreak?
Why is the prevalence of SARS-CoV-2 infection lower in children than in adults?
Is the infectivity of a patient positively related to the severity of the disease?
What is the proportion of asymptomatic carriers worldwide and what role do they play in transmission?
What is the probability that a cured patient is re-infected with SARS-CoV-2?
How does SARS-CoV-2 invade other organs than the lung?
Can animal experiments find out the specific pathogenesis of SARS-CoV-2 infection?
How long will it take to develop effective vaccine or medicine against SARS-CoV-2?

SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2.