SARS-CoV-2 can spread easily and sustainably between people. It can be spread to those who are pre-symptomatic and asymptomatic.
Many people who become infected with SARS-CoV-2 only experience very mild symptoms. This is especially characteristic for those in the beginning stages of the disease.
A pre-symptomatic case of COVID-19 occurs when an individual is infected with SARS-CoV-2 but does not exhibit symptoms during testing. However, that individual may develop symptoms during the infection.
An asymptomatic case of COVID-19 occurs when an individual is infected with SARS-CoV-2 and does not show any symptoms during the entire course of infection.
8. Imada, E. (2016). "Centers for Disease Control and Prevention (CDC) quarantine stations, respond to sick travelers at 18-U.S. international airports, and land border ports of entry, where most international travelers arrive." CDC.gov.https://phil.cdc.gov/Details.aspx?pid=22425
