Exactly thats what i said , The Dangerous part for the govt are Asymptotic people aka those who dont show symptoms . No one can test entire population not even China .
They do tracing matrix like history of air travel , people 's contact , aka lot of factors like his health history .
Best solution is self isolation because Corona is fatal for people with weak immunity . If South korea could stop it what stops other countries .
There was no quarantine in Korea (or any marts being emptied) tho..... I am French living in Seoul for 9 years now, and imo what Korea did wont be easily reproduced elsewhere in a couple of weeks unfortunately.
For starters, Korea has painfully experienced few years ago with MERS what every other countries is living now : how bad their healthcare system was prepared to tackle it and how overwhelmed they became back then (as far as i know Korea is one of the countries which had the most death during MERS)...
So as soon as corona in China started to be covered in the news, while most countries thought it's just a flu and didnt do shit, Korea took some preventive measures and asked domestic bio companies to develop diagnostic kits : eventually at least 2 companies successfully commercialized some which were mass-produced in a short time...
When a patient is identified here, in a few hours the govt publicly disclose their route for previous days by tracking their gps signal and credit card usage (while keeping their personal information anonymous). So by testing early many people especially the ones that had been in contact with the patients, regardless they have symptoms or not, it was possible to proactively treat them and only ask a limited number of people to stay at home. On a voluntary basis some companies asked their employees to work from home when one case was discovered inside their office but that's pretty much it.
Also you need to understand people in Korea are used to wear anti-pollution masks coz of fine dust coming from China. While a part is imported, there are several masks manufacturers in Korea so they rapidly increased the production to avoid any shortage.... for few days when the demand surged the price got a bit crazy and it was hard to find them in stores or even online, but the govt rapidly decided to control the entire supply distribution and fixed the prices. Now every week you can buy 2 masks per person in pharmacies for abt $3, people are just calmly queuing and no one is panicking.
I could talk much more abt how things are handled here but i think it's long enough already haha