Food Borne Diseases in Australia: Causes, Risks & Prevention

Key Takeaways

• Widespread Impact: Food borne diseases affect about 4.1 million Australians each year, with cases ranging from mild gastroenteritis to severe infections like listeriosis.
  
• Main Causes: Contamination can occur through bacteria, viruses, parasites, natural toxins, and chemical residues.
  
• High-Risk Foods: Raw eggs, deli meats, soft cheeses, shellfish, and pre-packed salads are among the most common culprits.
  
• Prevention: Proper food handling, hygiene, cooking, and storage practices significantly reduce risk.
  
• Vulnerable Groups: Pregnant women, older adults, children, and immunocompromised individuals are most at risk.
  
• Legal Standards: Australia enforces strict food safety laws through FSANZ and local health authorities to protect consumers.
  
• Action Steps: Get accredited food safety training, follow temperature control guidelines, and seek medical attention for severe symptoms.
  

Introduction

Food borne diseases are a major public health concern in Australia, affecting millions each year. These illnesses range from mild digestive upset to life-threatening infections such as listeriosis and hepatitis A.

Whether you work in hospitality, handle food professionally, or prepare meals at home, understanding the causes of food borne diseases is essential to keeping food safe and preventing illness.

This guide explores what causes food borne diseases, their main contaminants, the types of high-risk foods and environments, and the most effective prevention methods to ensure food safety.

Understanding Food Borne Diseases

Definition and Overview

Food borne diseases—often referred to as foodborne illnesses—occur when contaminated food or drinks are consumed. The contamination may come from microorganisms, chemicals, or natural toxins that lead to symptoms such as nausea, diarrhoea, fever, and vomiting.

Common examples include:

• Gastroenteritis – Caused by norovirus or Salmonella, leading to stomach and intestinal inflammation.
  
• Listeriosis – Caused by Listeria monocytogenes; particularly dangerous for pregnant women, newborns, and older adults.
  

Food Borne Disease vs Food Poisoning

While “food poisoning” is the commonly used term, food borne disease is broader.

• Food borne disease: Covers all illnesses caused by contaminated food.
  
• Food poisoning: Usually refers to bacterial or viral infections specifically.
  

Prevalence in Australia

According to Food Standards Australia New Zealand (FSANZ), approximately 4.1 million cases of food borne illness occur annually. While most are mild, some lead to hospitalisation or death.
Outbreaks are more common in aged care facilities, childcare centres, and restaurants, where large-scale food preparation and vulnerable populations intersect.

Biological Causes of Food Borne Diseases

Bacteria

Bacteria are the most common cause of food borne illness. Major culprits include:

• Salmonella – Found in raw eggs, poultry, and unpasteurised milk.
  
• Escherichia coli (E. coli) – Especially E. coli O157:H7 in undercooked beef and contaminated produce.
  
• Campylobacter – Common in undercooked poultry and unpasteurised dairy.
  
• Listeria monocytogenes – Can grow even in refrigerated food such as deli meats and soft cheeses.
  

Viruses

Viruses don’t multiply in food but can be transmitted through contaminated water or surfaces:

• Norovirus – Extremely contagious, often spread through shellfish and salads handled by infected individuals.
  
• Hepatitis A – Spread via poor hygiene or contaminated water, particularly in ready-to-eat foods.
  

Parasites

Less common than bacteria or viruses but still significant:

• Giardia and Cryptosporidium – Found in untreated water and raw produce.
  
• Toxoplasma gondii – Found in undercooked meat, especially pork and lamb.
  

Fungi and Moulds

Some fungi produce mycotoxins, which are toxic even in small amounts:

• Aflatoxins – Produced by moulds on improperly stored grains, nuts, and legumes.
  

Chemical and Environmental Contaminants

Natural Toxins

Naturally occurring toxins can be found in:

• Ciguatera toxin – Found in reef fish such as barracuda and red snapper.
  
• Aflatoxins – Common in foods stored in warm, humid conditions.
  

Chemical Contaminants

Chemical contamination can happen during production or preparation:

• Pesticide residues – From agricultural spraying.
  
• Cleaning chemicals – Left on food contact surfaces due to improper rinsing.
  
• Heavy metals – Like mercury (in large fish) and lead (from old plumbing).
  

Allergens

Allergens can trigger severe reactions, including anaphylaxis. Common ones include:
Peanuts, eggs, milk, wheat, soy, and shellfish.
Australia’s Food Standards Code mandates clear allergen labelling to help consumers avoid unsafe products.

Food Handling and Storage Practices

Poor Personal Hygiene

Food handlers may spread pathogens through:

• Unwashed hands
  
• Preparing food while sick
  
• Lack of gloves or hair restraints
  

Cross-Contamination

Occurs when bacteria transfer from raw to cooked foods via:

• Shared cutting boards or utensils
  
• Unwashed hands or contaminated surfaces
  

Time-Temperature Abuse

Bacteria grow rapidly between 5°C and 60°C (the “danger zone”).
To prevent this:

• Keep cold foods below 5°C
  
• Keep hot foods above 60°C
  
• Reheat leftovers to at least 75°C
  

Inadequate Cooking or Reheating

Undercooked foods can retain harmful microorganisms:

• Poultry: 75°C
  
• Minced meat: 71°C
  
• Leftovers: 75°C
  

High-Risk Foods and Environments

High-Risk Foods

Foods more likely to harbour pathogens include:

• Raw eggs and homemade mayonnaise
  
• Deli meats and pâtés
  
• Soft cheeses like brie and camembert
  
• Raw shellfish
  
• Pre-packaged salads and cut fruits
  

High-Risk Environments

Outbreaks are more frequent in:

• Childcare centres
  
• Aged care facilities
  
• Cafés and restaurants
  
• Outdoor events and festivals
  

These environments often involve bulk food preparation and limited temperature control, increasing the risk of contamination.

How to Prevent Food Borne Diseases

Safe Food Handling Tips

• Wash hands thoroughly before and after handling food.
  
• Clean and sanitise all utensils and surfaces.
  
• Use separate chopping boards for raw and cooked items.
  
• Avoid preparing food if unwell.
  

Storage and Labelling Best Practices

• Store raw and cooked foods separately.
  
• Follow “use by” and “best before” dates.
  
• Use the FIFO (First In, First Out) method.
  
• Refrigerate leftovers within two hours.
  

Staff Training and Certification

Food handlers should complete accredited training such as SITXFSA005 – Use hygienic practices for food safety.
Training ensures compliance with legal standards and reduces the risk of outbreaks in food service settings.

Legal Standards and Public Health Initiatives

National Food Safety Standards

The Australia New Zealand Food Standards Code (administered by FSANZ) governs hygiene, labelling, and food safety protocols.

State-Level Regulations

Local enforcement is managed by:

• NSW Food Authority
  
• ACT Health Protection Service
  
• Victorian Department of Health
  

Notifiable Disease Reporting

Diseases like Salmonella, Listeria, and Hepatitis A are notifiable, meaning confirmed cases must be reported to health authorities to contain outbreaks.

When to See a Doctor

Mild vs Severe Symptoms

Mild symptoms:

• Nausea, vomiting, diarrhoea, mild cramps
  

Severe symptoms:

• Blood in stool
  
• High fever
  
• Persistent vomiting or diarrhoea
  
• Signs of dehydration
  

Seek medical care if symptoms persist, especially after consuming high-risk foods.

Vulnerable Populations

Those at higher risk include:

• Pregnant women
  
• Older adults
  
• Children under five
  
• People with weakened immune systems
  

Frequently Asked Questions (FAQ)

What are the main causes of food borne diseases?

Contaminants such as bacteria, viruses, parasites, natural toxins, and chemicals.

Can viruses or parasites cause food poisoning?

Yes—examples include Norovirus, Hepatitis A, and Toxoplasma gondii.

Which foods are most likely to cause illness?

Raw eggs, shellfish, soft cheeses, and pre-packaged salads.

How can I tell if food is contaminated?

Spoilage signs may include off smells, discolouration, or slime, but contamination isn’t always visible.

How soon do symptoms appear after eating contaminated food?

Usually within 1 hour to 3 days, depending on the contaminant.

What should I do if I suspect food poisoning?

Stay hydrated, rest, and seek medical help for severe symptoms. Report cases linked to public venues.

How can food businesses prevent outbreaks?

Train staff, maintain hygiene, enforce safe food handling procedures, and meet certification requirements.

Final Thoughts

Food borne diseases are largely preventable with the right knowledge and practices. By following hygiene standards, monitoring temperatures, and adhering to Australia’s strict food safety laws, individuals and businesses alike can play a key role in reducing the risk of illness.