@Anonymous Coward re quarantine, research motivation
My mother picked up dengue in Singapore, it took her a year to get over it; longer if you count the reminiscing. The isolation idea should polish off air travel then. No big loss, IMHO.
The second point, about motivation, is complex. The company I work at provides WHO with the current combination malaria therapy at cost, a major logistics project. It has also a research centre into dengue and other tropical diseases in Singapore. Research pride, hoped-for spill-overs, loss-leaders and good citizenship all contribute, as well as profits, I suggest.
Those fighting epidemic diseases have a depressingly counter-intuitive set of priorities - they live in a strange world, poor chaps. CDC, one of the citations in a good wiki article, blames poor infrastructure from uncontrolled urban growth, deteriorating public health infrastructure, passive health surveillance systems, panic mentality, unwitting GPs, increased travel, ineffective mosquito control - but not global warming or lack of research.
There are increased rates of fatal complications if you catch a second strain of dengue, and, if I recall correctly, the strains are getting nastier too.