Salmonella infection

Salmonella bacteria can infect both people and animals, and can also grow in food and the environment.

You become infected with Salmonella by ingesting the bacteria through your mouth. This can be by:

• eating contaminated, undercooked meat (most commonly chicken)
• eating contaminated raw or undercooked eggs
• eating food that contains raw egg butter
• eating food that has been cross-contaminated with Salmonella from raw foods (especially meats, poultry and eggs)
• handling pets, other animals, raw meat and pet meat
• drinking water that has been contaminated, usually by animals or sewage.

Person-to-person spread can happen if you come into contact with microscopic amounts of faeces (poo) from an ill person. Such spread may occur directly by close personal contact, or indirectly by touching contaminated surfaces such as taps, toilet flush buttons, toys and nappies.

Symptoms usually start between 6 hours to 7 days (usually 1 to 3 days) after you have ingested the bacteria and typically last for between 2 to 7 days.

Symptoms can include:

• diarrhoea
• stomach cramps
• nausea and vomiting
• fever
• headache.

Salmonella typhi and Salmonella paratyphi are certain types of Salmonella bacteria that cause typhoid and paratyphoid fever, which affect the whole body, not just the digestive tract.

There are many causes of gastroenteritis, and laboratory testing of a faecal specimen is necessary to confirm that symptoms are due to Salmonella infection.

People with confirmed or suspected Salmonella infection should:

• Drink plenty of fluids such as water or oral rehydration drinks (available from pharmacies) to avoid dehydration. Dehydration is especially dangerous for babies and the elderly.
• Avoid anti-vomiting or anti-diarrhoeal medications unless prescribed or recommended by a doctor.

People with typhoid or paratyphoid fever will require antibiotic treatment.

If you experience severe or prolonged symptoms you should visit a doctor.

• Do not go to work or school for at least 24 hours after symptoms have finished, or 48 hours if you work in or attend a high risk setting, such as health care, residential care or child care, or handle food as part of your job.
• People with typhoid or paratyphoid fever who work in a high risk setting as described above will be contacted by their local public health unit to discuss extra precautions.
• Wash and dry your hands thoroughly after going to the toilet.
• Avoid preparing or handling food and drinks for other people in your household until at least 24 hours after your symptoms have finished. If you must prepare or handle food, thoroughly wash your hands beforehand to reduce the risk of spreading the infection to others.
• Immediately remove and wash using detergent and hot water any clothes or bedding contaminated with vomit or diarrhoea.
• After an episode of diarrhoea or vomiting, clean contaminated surfaces (for example benches, floors and toilets) immediately using detergent and hot water. Then disinfectant surfaces using a bleach-based product diluted according to manufacturer’s instructions. 
• Clean carpet or soft furnishings contaminated with diarrhoea or vomit immediately using detergent and hot water and then steam clean.

• Avoid contact with people who have gastroenteritis symptoms.
• Wash and dry your hands thoroughly after going to the toilet, handling animals, changing nappies or cleaning up vomit or diarrhoea, and before eating or drinking. If hand-washing facilities are not available use an alcohol-based gel.
• Raw meats, especially poultry, can contain Salmonella bacteria. Keep raw foods separate from cooked and ready-to-eat foods (for example salads) to prevent cross-contamination. Store raw meat below ready-to-eat food in the refrigerator and use separate chopping boards and knives for raw and ready-to-eat foods.
• Keep cold food below 5 °C and hot food above 60 °C.
• Cook meat and poultry thoroughly to a temperature of 75 °C or until meat juices run clear and are not pink.
• Do not use dirty or cracked eggs.

When travelling

When travelling to developing countries, especially in Asia, the Pacific islands, Africa, the Middle East and Central and South America, you should avoid:

• salads and fresh fruit salads
• raw or cold seafood, including shellfish
• raw or runny eggs
• cold meat
• unpasteurised milk and dairy products (including ice-cream)
• ice in drinks and flavoured ice blocks.

Fruit that you peel yourself is usually safe. Remember – ‘cook it, boil it, peel it, or leave it’.

Use bottled water or disinfect water (by boiling, chemical treatment or purifiers) for drinking and brushing teeth.

Read more about healthy international travel.

Is there a vaccine for Salmonella?

There are no vaccines that protect against most types of Salmonella. However, a typhoid vaccine is available for overseas travellers and can provide some protection. See your doctor or travel medicine specialist at least 2 months prior to departure to see if any vaccinations or medications are recommended.