The guy in the first video asked why they would look for place to quarantine people if it was a virus, like if quarantining was for anything else than for a disease. The word literally comes from the practice of isolating ships that came from infected ports for 40 days.
History of Quarantine | Quarantine | CDC.
The practice of quarantine, as we know it, began during the 14th century in an effort to protect coastal cities from plague epidemics. Ships arriving in Venice from infected ports were required to sit at anchor for 40 days before landing. This practice, called quarantine, was derived from the Italian words quaranta giorni which mean 40 days.