Seychelles, Vatican city, New Zealand, Fiji.
These are the country has been free from the wild disease covid19.
First of all, they put a lockdown in their countries and stopped people to meet them. As meeting from one another is the chain of spreading of this virus.
They furthermore guide and supported their infected people and recovered them as fast as they can.
Also, they used to sanitize the whole part of the country and they had been canceled all connection with the other countries such as trading, arrival, and departure from any other countries