This vaccine could represent a big step forward, with some caveats. Interestingly, it seems to be more effective in those who have already contracted dengue. Here is the New England
Journal of Medicine's take on it:
It appears to be approved for ages 9 and above and, while I've not seen any age restrictions on administration, it is a live, attenuated vaccine, so those with weakened immune systems should avoid it.
Dengue is a viral illness caused by any one of 4 serotypes. The vector is the Aedes aegyptus mosquito which, unlike the Anopheles mosquito, bites during the day and has an affinity for humans and human habitation, so one must be very careful to avoid bites at any time of day, particularly in urban areas. Up to 80% of infections are non-symptomatic, meaning you have it but don't know it. The majority of the symptomatic infections are mild and referred to as “dengue fever” with the more serious and uncommon 'dengue hemorrhagic fever (DHF) causing most morbidity and mortality. DHF is most commonly caused by re-infection by a second serotype after an earlier infection, thus tends to occur among people spending a lot of time in a “hyperendemic” area where all 4 serotypes can be found.
The 'take home' is don't get bit by mosquitos, wherever you are and whatever time off day. Cover up and don't be shy with the DEET. Don't bother with Skin so Soft and the like because, despite what the sailing magazine says, they don't work. If you are in an endemic area and you experience severe abdominal pain or tenderness, persistent vomiting, lethargy or restlessness, abrupt change from fever to hypothermia, bleeding, pallor, cold/clammy extremities, liver enlargement on physical exam, or abnormal mental status, get yourself to a hospital.