THIRTEEN hours in the air, eight toilets, and 26 passengers violently ill with gastroenteritis.

That was the scene when an international flight became the trip from hell after 26 passengers fell sick during a Qantas flight.



The group, believed to be a tour group travelling together, were sick before they embarked on the 13 hour and 51 minute flight from Santiago, Chile yesterday.

"The people were sick prior to the flight," a Qantas spokesman said. "It was a tour group that had food poisoning so it was contained to them."



A statement from the NSW Ministry of Health said the group had developed "vomiting and diarrhoea on the plane" consistent with norovirus infection, which is a common cause of outbreaks of gastroenteritis in Australia and elsewhere.



The flight was aboard a Boeing 747-400 which has a total of seven toilets located on the main deck and one on the upper deck.



A statement from the NSW Ambulance service said the 26 passengers were assessed at the scene.



"Of those, 16 patients required transport to hospital, three of whom were stretcher patients," the statement reads.



A total of 10 patients were transported to the Prince of Wales Hospital, the remaining six were transported to St George Hospital.



"Ambulance will assess the sick passengers, and if well enough to leave they can be cohorted through the airport with minimal exposure to other passengers," a Spokesperson from the Ministry of Health said.



"NSW Health has provided Qantas with a letter and factsheet about viral gastro to distribute to all departing passengers, as well as advice for cleaning and cabin staff."



As a precaution, other passengers have been advised to keep a close eye on their health over the next 24 to 48 hours and seek medical advice if they become unwell.



Scores of family members were left high and dry in the arrivals hall with no official word from Qantas over the incident.



David Sanhueza and his family from Mount Druitt were left waiting two hours for his mother-in-law, Carmen Caro, visiting from Chile.



"They don't give you any information, there's nothing out of the speaker. I went and saw customer service but they wouldn't give me anything," he said.



Her granddaughter Jennifer Sanhueza said the family only found out what was going on from the news.



"We weren't told much, we only heard from a phone call that it was all over the news," she said.



Mrs Caro said the the group that got on in Brazil had been vomiting the whole flight.



"A whole lot of kids got on the plane at Brazil and they were all vomiting and sick," she said in Spanish translated by her granddaughter.



Bernie Herrenberg was left waiting balloons in hand for the return of his 23-year-old daughter Stefanie.



"I've been waiting and all I know is what my daughter SMSd me," he said.



The SMS shown to The Daily Telegraph read: "Woo just landed! So our plane is being quarantine because there were heaps of people with a bad virus on it. I have no idea how long it will take but it will definitely delay us."