THE NSW Food Authority has confirmed that at least three cases of hepatitis A have been traced back to contaminated semi-dried tomatoes from Victoria, which are being blamed for a large outbreak of the disease.
NSW Health has issued a warning not to eat loose semi-dried tomatoes unless they have been thoroughly cooked and has alerted medical staff to look out for patients with symptoms of the liver disease.
An investigation in Victoria has identified more than 80 people with hepatitis A, two-thirds of whom ate semi-dried tomatoes - bought from delicatessens or eaten at cafes and restaurants - before getting sick.
Half of them were taken to hospital for treatment.
In the past two months, five people in NSW who had not travelled overseas had contracted the disease and three of them had eaten semi-dried tomatoes in the weeks before getting sick.
By comparison, six locally acquired cases were reported in NSW for all of last year.
A spokeswoman for the NSW Food Authority confirmed yesterday that the three cases since August 15 had been traced back to Victoria, although she could not explain how.
"Essentially, there were three cases the Food Authority was asked to follow up on. Tracebacks were conducted and the product was traced back to Victoria," she said.
The authority has passed on the information to the Victorian Department of Human Services, which is leading the investigation, the spokeswoman said.
Symptoms of hepatitis A, which include fever, nausea, poor appetite, abdominal discomfort, dark urine and jaundice, develop between two and and seven weeks after exposure.
The disease is spread when traces of faecal matter containing the hepatitis A virus contaminate hands, objects, water or food and are then taken in by mouth.
The director of communicable diseases at NSW Health, Jeremy McAnulty, said a "painstaking" process was under way to determine the suppliers and retailers but it would not be made public.
"It's information that is confidential because it doesn't imply that the retailers or suppliers caused the contamination," Dr McAnulty said.
"It's a very complex web of how the product is distributed throughout the marketplace.
"Despite a comprehensive and complex investigation, no single supplier of semi-dried tomatoes has been proven to be the cause of the Victorian outbreak." He said the outbreak was not clustered in any one part of Victoria.
Cases of hepatitis A in NSW have dropped markedly since 1997 - when there was an outbreak on the North Coast due to contaminated oysters - falling from about 1000 a year to less than 100 as a result of improved food handling practices and sewage disposal.
Last year there were 69 cases and so far this year there have been 73 cases.
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