NCOVDATA.IO

We assume that there is a fixed pool of people travelling by air from China to other countries, and within this pool the passengers have different probabilities of being infected depending on which city they are flying from (this probability is defined as the outbreak size divided by the population size for that city). We use the FLIRT tool from EcoHealth Alliance to simulate passenger flows from four Chinese cities - Wuhan, Beijing, Shanghai and Guangzhou - and then use that to estimate how the above passenger pool is divided up between the destination countries. The resulting proportions become relative risk values... Because these results are based on a simulation rather than actual passenger data, we do not get individual passenger numbers and thus do not estimate absolute risk values. The advantage of it being a simulation is that it takes into account passengers who transfer between flights, in addition to the passengers who take direct flights... We then use these relative..