Health authorities in New South Wales and Tasmania are investigating separate outbreaks of food poisoning which affected large numbers of people who ate foods containing raw eggs.

The New South Wales Food Authority (NSWFA) and NSW Health are investigating up to 49 cases of Salmonella poisoning while in Tasmania more than 150 people were affected in the Hobart area.

Tasmania’s Director of Public Health, Dr Roscoe Taylor, said 168 people have been interviewed in relation to the outbreak involving several catered functions and some restaurant patrons.  

Of these, 79 have been identified as suffering from gastroenteritis symptoms, and 41 cases have been laboratory confirmed as being caused by Salmonella .

“The Public and Environmental Health Service is aware of at least eight patients who have been admitted to hospital over the course of the outbreak, most of whom have since been discharged,” Dr Taylor said on 7 February.

While the numbers could still grow as results return from laboratory testing, the outbreak was contained promptly and all cases dated back to exposures between the 23rd and 25th of January, he added.

“Salmonella has now been isolated from a Tartare sauce sample containing raw egg.”

Dr Taylor said public health evidence indicates that many raw foods carry an increased level of risk of Salmonella and other food borne infections, but such foods are often consumed as part of our normal eating habits.

On 15 February he announced new food safety measures designed to prevent further outbreaks of Salmonella gastroenteritis associated with the consumption of raw egg products.

Under the new requirements all food businesses choosing to make raw egg products must document the method of manufacture and follow strict and auditable procedures governing egg receipt, product preparation, storage and handling.  

The shelf life of each batch of raw egg product will also be limited to no more than 24 hours under refrigeration, after which the product must be discarded.

Dr Taylor said the new egg safety measures will be legally enforceable by local government environmental health officers, as part food business licensing and inspection procedures.

In NSW the poisonings occurred in outbreaks in Wagga Wagga and the Sydney area in the six weeks leading up to Christmas. The NSWFA immediately issued a media release strongly advising against eating raw egg products.

Investigations revealed that all the cases involved reports of illness after people prepared and ate their foods at home, prompting the NSWFA to remind consumers about the safe preparation of raw egg products in the home.

NSWFA Director-General George Davey said eggs are a good, nutritious food and should be eaten as part of a balanced diet, but they do need to be handled properly.

“Eating foods containing raw egg products, like all raw foods from animals, presents a risk of food poisoning,” Mr Davey said.

The risk may be greater for those who are pregnant, older people or very young children and those with medical problems involving impaired immune systems, he added.

In the recent reported incidents, 11 people fell ill from eating Caesar salad containing a raw egg dressing or chocolate mousse also made with raw eggs, while three children were affected after drinking eggnog made with raw eggs.

The authorities suspect a further 35 people succumbed after eating homemade fried ice cream at a party in Wagga Wagga. The ice cream was prepared with a coating made from raw egg batter.

“Eggs can contain some bacteria on the outside of the shell that can easily transfer to the white and yolk when broken,” Mr Davey said.

“This is why we see foods like raw egg mayonnaise or mousse desserts implicated in Salmonella food poisoning. If these foods containing raw eggs are left out of the fridge for long periods, the Salmonella have a perfect environment to grow in.

'People should take care when preparing foods containing raw or undercooked eggs like homemade sauces or dressings such as mayonnaise, cake or biscuit batter, mousse, uncooked meringue, eggnog, eggflip or other drinks containing raw egg products.

“To enjoy eggs safely, make sure the shells are not cracked, broken or dirty and always store them in a refrigerator at 5 degrees C or below.

“If you choose to consume raw egg product make sure that you use it immediately after making, or refrigerate it.”

Also, use eggs within three to five weeks of buying them and always observe the ‘use by’ date on the container. Keep eggs away from other foods and always wash and dry your hands. After working with eggs, always clean surfaces, sinks, dishes and utensils thoroughly.

“Cooking eggs properly kills bacteria, but bacteria will survive in foods that are not cooked thoroughly. This is why you should be very careful if using raw eggs in food that will not be cooked,” Mr Davey said.

More information about buying, storing and using eggs is available in a fact sheet on the Authority’s website: www.foodauthority.nsw.gov.au/consumer/c-safe-use-of-eggs.asp

The NSWFA is the NSW government agency responsible for regulating food production and food safety throughout the state. The Authority is introducing a new Egg Food Safety Scheme which will ensure that eggs continue to be a safe food for NSW consumers.

Source: FSANZ Food Surveillance News - Autumn 2008