Phuket tourists stung, but not by actual jellyfish

The first-aid providers said the stings were not dangerous this time, delivered most likely by Portuguese man-o-war (Physalia physalis), also known as bluebottles due to their bright-blue colour. 
Rather than a single jellyfish, a bluebottle is in fact a siphonophore – a colony of smaller organisms. 
The lifeguards also pointed out that jellyfish don’t “attack” people. They have little control over where they swim or float and navigate largely by light, tides and waves.
“People just swim into jellyfish, or in this case bluebottles that have been broken up by wave action but continue to float around with their stingers intact,” one lifeguard said.
The Portuguese man o’ war is a marine hydrozoan of the family Physaliidae and is found in the Atlantic, Indian and Pacific oceans. 
Its long tentacles deliver a painful sting that is venomous and powerful enough to kill fish, but rarely humans. 
The multi-cellular organism is made up of individual animals of the same species called zooidsor polyps. The polyps are attached to one another and physiologically integrated, to the extent that they cannot survive independently.
Thus a symbiotic relationship is created, requiring all of the polyps to work together and function like an single animal.
Treatment for bluebottle stings varies somewhat from that applied for actual jellyfish stings.