Sahara dust comes and goes. That's what happens this time of year.
If you don't want Sahara dust, don't vacation in the Caribbean between May and November. While we don't especially like it, it does keep hurricanes from developing.

Stinging plankton?

The last stretch of Sahara dust is all done. There have reportedly been some stinging jellyfish lurking around St John particularly but they too are apparently on the way out after leaving some swimmers with minor rashes but nothing serious. Following a particularly large annual influx of Sargassum weed, more seaweed (not Sargassum) showed up a week or so ago around STT and STJ but this too has passed.