That's really terrible...seriously. But what do you want everyone to do? Siga does not have a Dengue vaccine.
They are at least 5 to 10 years away from having an approved one, if ever. You do understand you have to have clinical trials and FDA approval before you can sell a vaccine to treat Dengue in human beings?
Saying you are working on something is not the same as actually having something that works in human beings and is safe. Siga is working on many cures or preventatives for many diseases and/or biological threats.
Thus far the only one they have is for smallpox and that one is not FDA approved either.