Organisers of Portugal's Waking Life festival have been left bemused by a bug at the event, which has left people suffering symptoms of vomiting and diarrhoea.
"At the moment we are trying to figure out the exact source of the illness that has been going around," the festival said in a Facebook statement. "What we are sure of is that it is not the tap water which we are using since July 1st for all food preparations and drinking. Also the lake water has been tested and proven to be safe. We are aware that throughout the festival some of our medical staff have been spreading that the tap water was not drinkable. However, this was based on nothing but an assumption. Later the head of the medical team apologised for this misinformation."
Party-goers have been sharing their personal experiences in response to the post, with some complaining the illness cost them financially due to missed flights although overall attendees had a positive and understanding response.
Organisers advised those affected to "take something for the stomach, hydration sachets and eat healthy. It should fix you in about a day or two."