We are aware of a very small number of case reports in which it's suspected that asymptomatic transmission may have occurred, but these have not been verified. In fact, with regard to the New England Journal study, there's now been a publication to say that it was incorrect and that this person was, in fact, symptomatic and had been taking some medication that suppressed his fever, for example. That's a very important fact to verify and correct. I'm very happy that German scientists and WHO have verified that.
We have heard other potential reports, which have not been substantiated. What we know is that it could possibly happen, but we think it would be rare and very unlikely that asymptomatic persons would be the key driver of an actual outbreak or epidemic. Of course, the evolving description of the patients has shown that they can have quite mild to more severe symptoms, so some of the recommendations right now are for people to, for example, monitor their symptoms very carefully, potentially reduce contact with others and, at the earliest moment they feel any kind of symptom, seek medical care. I think that is very important. It's really a droplet-spread disease. It's when someone's coughing most vigorously and they're more symptomatic that, we believe, this virus is transmitted.