New Australian National University research has found the incidence of foodborne illness has declined slightly and that one quarter of the 16 million cases of gastroenteritis each year are caused by food contamination.
The research tracked the changes in foodborne illness in Australia between 2000 and 2010.
It found the number of cases of foodborne illness fell by 17 per cent, but the number of cases of the two leading causes of hospitalisation, Salmonella and Campylobacter, increased by 24 per cent and 13 per cent respectively.
"On average, each Australian has an episode of foodborne gastroenteritis once every five years," said Associate Professor Martyn Kirk from the National Centre for Epidemiology and Population Health.
"Australian authorities have worked hard in the last decade to ensure a safe food supply, so it is disappointing not to see a decline in Salmonella and Campylobacter infections," he said.
Salmonella bacteria can be carried in undercooked chicken or eggs, while Campylobacter is commonly found in raw or undercooked poultry meat and raw milk.
While the number of Salmonella and Campylobacter cases increased, they accounted for only around five per cent of cases of foodborne illness.
Associate Professor Kirk said the microbiological cause of 80 percent of foodborne illnesses remained unknown.
"People often don't find out the cause of their illness, either because they don't visit a doctor, or they don't have a test," said Associate Professor Kirk.
The research also found an 85 per cent decline in cases of Hepatitis A virus infection as a result of vaccination campaigns.
In a second paper the researchers looked at four illnesses that can result from gastro; Guillain-Barré syndrome (GBS), haemolytic uremic syndrome (HUS), irritable bowel syndrome (IBS), and reactive arthritis (ReA).
They found nearly one per cent of gastro cases, around 35,840 people, subsequently developed one of these illness, with 1,080 people hospitalised and 10 deaths.
Co-researcher Dr Kathryn Glass said people can avoid foodborne illness by keeping their hands clean when preparing food, keeping food refrigerated, keeping cooked and raw meat separate, and by ensuring meats are properly cooked.
"The key thing is that people who are infected should maintain good hygiene, including washing their hands and not preparing food while they are ill," she said.
The findings have been published in two papers in the US Centers for Disease Control and Prevention journal Emerging Infectious Diseases.
The research was funded by the Commonwealth Department of Health, Food Standards Australia New Zealand and the New South Wales Food Authority.