The father of a boy admitted to Sutherland Hospital after an outbreak of food poisoning linked to a bakery in Sydney's south said victims and their families were "very angry".
NSW Health said 40 people had presented at St George and Sutherland hospitals since Saturday with symptoms of food poisoning, while 13 of those people were admitted to hospital for treatment.
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Bakery linked to salmonella outbreak
NSW Food Authority is investigating a bakery in Sydney's south after about 40 people have been treated at hospital for suspected salmonella poisoning. (Vision: Today Show, Channel Nine and Audio: 2UE)
But Engadine building contractor Damian Sullivan disputed these figures, saying hospital staff had told him the number of people struck down was close to 100, rather than 40.
Mr Sullivan said his son Cooper, 11, ate a chicken and salad roll from Box Village Bakery and Cafe in Sylvania for lunch on Sunday.
"Cooper started feeling sick on Sunday night and when we took him to the GP on Monday he said, 'take him straight to hospital'," Mr Sullivan said.
"He is not well, and he will have to stay in hospital for at least another day. [We] are going to have some things to say [to the owners]."
Mr Sullivan said he and his daughter Tia, 5, had also eaten chicken and salad rolls from the bakery on Sunday, but had not yet become ill.
"We were told we could still get sick, because salmonella can hit you any time from 24-72 hours," he said.
Professor Mark Ferson, the director of the Public Health Unit at the South Eastern Sydney Local Health District, confirmed salmonella bacteria had been found in some of the patients.
"They've presented with diarrhoea, vomiting, stomach cramps, fever, aches and pains, and we have some positive salmonella results on early tests on some of those people," he said.
"Salmonella infection can be mild, but can be very nasty. People can get dehydrated and quite sick with salmonella."
Box Village Bakery and Cafe has been closed while the NSW Food Authority conducts and investigation.
Salmonella infection can be mild, but can be very nasty. People can get dehydrated and quite sick with salmonella.Professor Mark Ferson
One angry father, Ross Paull, placed a note on the door of the bakery on Tuesday, saying "you made my family very sick!!".
Patients reported eating a variety of food, including chicken and pork rolls, from the same bakery, Dr Ferson said.
Salmonella is mainly spread to humans when they eat under-cooked food made from infected animals. Symptoms often start 6-72 hours after infection and usually last for 4-7 days, although they sometimes last longer.
Those who presented at hospitals in the Sutherland Shire ranged from young children to the elderly, Dr Ferson said.
He also said the number of people who fell ill in the outbreak could be higher than 40, as some people would have gone to their GP rather than to hospital for treatment.
One woman, Katrina, said her two sons, aged 17 and 18, both fell extremely ill on Friday after eating chicken rolls from Box Village Bakery and Cafe, however she did not take them to hospital because of the severity of their symptoms.
"The only reason we didn't take ours [her sons] to hospital was because they couldn't get out of the bathroom long enough to travel anywhere," Katrina told radio station 2UE.
"We took them to the medical centre. I sent my husband up to see how long the line was so they didn't have to wait there. They were very, very sick."
Another man, Emmanuel, told the radio station that five of his son's friends who also ate at the bakery also fell ill. Three of those friends had to be put on drips at hospital, he said, but were now recovering at home.
Dr Ferson said some people could be hit worse by salmonella infection.
"People who are frail and elderly, people with other medical conditions where fluid balance is important, and people with other underlying conditions clearly are going to be more at risk of getting sick," he said.
The bakery will remain closed until the investigation is complete.