There is always the question of whether to study things bottom-up or top-down. These are bottom-up studies of what to do if you have a single infected patient. If you had an individual infected with a novel cold, that would be important, but we are generally interested in epidemics. In particular, why do colds go epidemic in the winter? We know there must be some environmental change. Maybe it’s a small change, since it only takes a small change in reproduction number to cause an epidemic. Then these controlled experiments might identify the main method of transmission. But maybe the change from summer to winter is a big change that swamps the effects we can measure in these bottom-up experiments.
There is always the question of whether to study things bottom-up or top-down. These are bottom-up studies of what to do if you have a single infected patient. If you had an individual infected with a novel cold, that would be important, but we are generally interested in epidemics. In particular, why do colds go epidemic in the winter? We know there must be some environmental change. Maybe it’s a small change, since it only takes a small change in reproduction number to cause an epidemic. Then these controlled experiments might identify the main method of transmission. But maybe the change from summer to winter is a big change that swamps the effects we can measure in these bottom-up experiments.