I haven't seen the movie. Going by the discussion so far it looks like a technothriller.
We have some guidelines about technothrillers. If we classify Contagion as a technothriller, then questions such as this one, which are about a mundane element, are off-topic.
However, I'm not sure about the classification as a technothriller. Going by Wikipedia's plot summary, it looks like not only the disease is fictional, but the disease's properties are somewhat romanticized. When you start romanticizing scientific elements, that's science fiction.
In any case, for a borderline topic like this, I'm inclined to leave the question around. Since we cannot migrate the question because it is too oldcannot migrate the question because it is too old (a stupid restriction, but not one that moderators can do anything about), migrating to Movies.SE isn't an option. I prefer leaving the question open to closing it which would make it deletable.