The one error is the spark that starts the forest fire. Yes, the forest needs to be dry. But we don't want to carry all the water every day to keep it wet. The

The one error is the spark that starts the forest fire. Yes, the forest needs to be dry. But we don't want to carry all the water every day to keep it wet. The case here https://ncov.moh.gov.vn/ https://ncov.moh.gov.vn/ on "11:00 25/07/2020" seems to be a local transmission if the google translation is correct. The infection must have happened two weeks ago and they are currently contact tracing. Taking an average of 4 days, we are now on generation 2-3 of follow-up cases (or even more if the infection source/chain is older and has been spreading for a longer time). Let's hope that nobody else got infected and there are no asymptomatic patients running around by now, unaware that they are spreading it all over the country. Taking an R0 of 3 (since they don't have any hard measures right now), we are currently expect 3 * 3 * 3 cases if this person somehow got it from out of country. Finding those cases could take a bit of time and then we would look at 3 times more cases to find every 4 days. Assuming that some youngster got it and this older person is the first one to go to the doctor we could easily have 3 * 3 * 3 * 3 * 3 * 3 = 729 cases by now and that would probably already be out of control without instating a hard lockdown on all possibly affected regions and testing the whole population like China did.