What Is Salmonella?
Salmonella is a type of bacteria responsible for foodborne illness in both humans and animals. It is one of the leading causes of food poisoning in Australia, frequently linked to raw eggs, poultry, and fresh produce.
There are two main types:
- Typhoidal – causes typhoid fever.
- Non-typhoidal – causes food-related illness and is the most common in Australia.
Symptoms usually develop 6 to 72 hours after ingestion and may include:
- Diarrhoea
- Abdominal cramps
- Fever
- Vomiting
Due to its health impact and high outbreak frequency, salmonella remains a major public health concern in Australia.
How Salmonella Causes Foodborne Illness
After ingesting contaminated food or water, salmonella bacteria travel to the intestines and invade the intestinal lining. The immune system responds with inflammation, resulting in gastrointestinal symptoms. In severe cases, the bacteria may enter the bloodstream, leading to more serious infections, especially in high-risk individuals.
Salmonella Cases in Australia
Salmonella is one of the most reported notifiable gastrointestinal infections in Australia.
- Around 17,000 cases reported annually.
- Queensland and New South Wales report the highest numbers.
- Incidence increases during warmer months due to higher food spoilage risk.
Common Foods Linked to Salmonella in Australia
Raw or Undercooked Eggs
- Contamination can occur inside or on the shell.
- Backyard eggs pose a higher risk due to inconsistent hygiene.
- Dishes like aioli, mayonnaise, and tiramisu should only be made with pasteurised eggs.
Poultry (Chicken, Turkey, Duck)
- Salmonella is naturally present in the intestines of birds.
- Can spread during processing.
- Cook poultry to at least 75°C as recommended by Safe Food Australia.
Raw or Undercooked Red Meats
- Includes beef, lamb, and pork.
- Ground meats are particularly risky.
- Proper storage, cooking, and avoiding cross-contamination are essential.
Unpasteurised Dairy Products
- Includes raw milk and soft cheeses like brie, camembert, and feta.
- Always choose pasteurised dairy to minimise risk.
Seafood and Shellfish
- Contamination can occur via polluted waters or improper handling.
- Raw oysters and undercooked shellfish are particularly hazardous.
Fresh Fruits and Vegetables
- Contamination often occurs during harvesting or packaging.
- Wash all produce thoroughly under running water.
Processed and Packaged Foods
- Occasional outbreaks linked to peanut butter, cereals, and frozen meals.
- Manufacturing faults and hygiene lapses are usually responsible.
How Salmonella Contaminates the Food Chain
From Farm to Fork
Contamination can happen at any point:
- Use of contaminated water or fertiliser.
- Poor hygiene during processing or slaughter.
- Unclean equipment and shared handling surfaces.
Cross-Contamination in Kitchens
One of the biggest risks in households and commercial kitchens:
- Using the same cutting boards or utensils for raw and cooked foods.
- Poor hand hygiene.
- Reusing cloths or gloves.
Who Is Most at Risk?
Certain groups are more susceptible to severe symptoms:
- Children under 5.
- Adults over 65.
- Pregnant women.
- People with weakened immune systems.
These individuals are more prone to hospitalisation and complications.
How to Prevent Salmonella Infections
Safe Food Handling
- Wash hands for at least 20 seconds before and after handling food.
- Use separate chopping boards for raw meats and vegetables.
- Clean all kitchen surfaces and tools with hot, soapy water.
Cooking and Storage Guidelines
- Poultry: 75°C.
- Ground meat: 70°C.
- Whole cuts: 63°C.
- Refrigerate leftovers within 2 hours.
- Keep fridge below 5°C.
Wash Produce Properly
- Use running water, even for produce with rinds like rockmelon.
- Scrub firm fruits and vegetables with a brush.
- Dry with clean cloths or paper towels.
Handle Eggs Safely
- Buy clean, refrigerated eggs.
- Avoid cracked shells.
- Store pointed-end down.
- Skip raw egg dishes unless using pasteurised eggs.
Recent Salmonella Outbreaks in Australia
2018: Egg-Linked Outbreak (NSW)
- Over 200 cases.
- Linked to contaminated eggs from a single farm.
- Triggered a nationwide recall.
2020: Salad Greens Outbreak (QLD)
- Dozens of people fell ill.
- Traced back to inadequate washing and cross-contamination during processing.
What to Do If You Suspect Salmonella
Common Symptoms
- Diarrhoea.
- Abdominal cramps.
- Fever.
- Vomiting.
- Headache.
Symptoms typically last 4 to 7 days.
When to See a Doctor
Seek medical attention if:
- Symptoms last more than a week.
- You notice blood in stools.
- The affected person is a child, elderly, or has a chronic illness.
Food Safety Tips for Workers and First-Time Employees
Hygiene Best Practices
- Stay home if experiencing gastro symptoms.
- Wash hands regularly and wear gloves correctly.
- Report unsafe practices or breaches in hygiene.
Get Trained in Food Safety
Completing a nationally recognised food safety course, such as SITXFSA005 – Use hygienic practices for food safety, is essential for anyone in:
- Hospitality.
- Food preparation.
- Retail.
- Aged care or childcare.
Frequently Asked Questions (FAQ)
What foods are most commonly contaminated with salmonella?
Eggs, poultry, undercooked meat, dairy, fresh produce, and occasionally processed foods.
Can vegetables or fruits carry salmonella?
Yes, especially leafy greens, sprouts, and melons.
How does salmonella enter meat or eggs?
From the animal’s intestines or contaminated handling environments.
Can salmonella spread from person to person?
Rarely, but possible through poor hygiene and faecal-oral contact.
What is the best way to prevent infection?
Thorough cooking, proper storage, and hand hygiene.
How long does salmonella infection last?
Typically 4 to 7 days, longer for high-risk individuals.
Who is most at risk?
Children, older adults, pregnant women, and those with weakened immune systems.
Does cooking kill salmonella?
Yes, heat above 70–75°C effectively kills the bacteria.
Should high-risk individuals avoid certain foods?
Yes, raw eggs, undercooked meat, unwashed produce, and unpasteurised dairy.
How often do outbreaks happen in Australia?
Thousands of cases are reported annually, often tied to handling or hygiene errors.
Final Thoughts
Salmonella remains a significant yet preventable health threat in Australia. Understanding how it spreads and knowing which foods are high-risk empowers individuals to make safer choices.
For food workers and first-time employees, proper hygiene and completing a recognised food safety course are essential steps towards protecting both customers and themselves.
