The Food Authority's Chief Scientist Dr Lisa Szabo said the best way to prevent the spread of infection is to avoid food preparation when you are unwell.
"Don't cook when you're crook is a good basic rule to apply whether you are cooking commercially or preparing food at home," Dr Szabo said.
"However, this warning applies particularly to food industry professionals who come into contact with the preparation and service of food for hundreds, if not thousands, of people.
"Under the Food Standards Code it is illegal for food handlers to handle food when they have a gastric illness. It is also illegal for food businesses to allow staff to work if they are aware they have a gastric illness.
"To put people to work when you know they're unwell, or to not declare an illness, could potentially put the health of many people at risk.
"Viral gastroenteritis is highly infectious and can be very easily passed from person to person through poor hygiene and food handling practices."
Dr Szabo said the first rule of food safety is to thoroughly wash and dry your hands before beginning to prepare or eat any meal, and to wash your hands after touching raw meat or poultry.
"Good and thorough hand washing removes dirt, leftover food, grease and harmful bacteria and viruses from your hands preventing them from spreading to food, work surfaces and equipment," she said.
Winter blues
"Outbreaks of viral gastroenteritis tend to increase during winter and I urge everyone to practice good food safety in the kitchen at all times but especially during the peak viral gastro season."
Symptoms of viral gastroenteritis can commonly include vomiting and diarrhoea and sometimes headaches and muscle aches.
Symptoms may take one to three days to develop and can last for one to two days, sometimes longer.
As a precaution it is recommended that people with gastro do not prepare food for 48 hours after their symptoms finish.
"The NSW Food Authority has introduced a variety of measures to help reduce the risk associated with foodborne illnesses," Dr Szabo said.
"This includes the introduction of the Food Safety Supervisor program which is designed to reduce foodborne illness in the hospitality and retail food service sectors in NSW by improving food handler skills and knowledge.
"The Food Safety Supervisor, or FSS, is a nationally recognised qualification that provides food businesses in NSW with high quality and consistent training in food safety procedures."
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