victims of a burn are advised by specialists to remain calm and remove themselves from the water before attempting to remove the tentacles from the wound - they also advise to only use fresh water from the sea to wash the affected area, and to apply vinegar to the wound, removing any remnants of the tentacles with tweezers.

the portuguese man-of-war mostly feeds on larvae, crustaceans and fish, and can often congregate in groups of 1,000 or more, residing in temperate waters like those enjoyed on rio's shores.