Most of the stories I have found are people that contracted it overseas (or now domestically) and then brought it back.
Here in Vietnam we have had 2 instances of Vietnamese citizens contracting it abroad. 1 in Italy, and the other in South Korea, these 2 returning individuals managed to infect around 10 people each on their flights back - most of these infected were foreigners. They (the 2 Vietnamese ladies) then went on to infect multiple locals closely connected to them.