Chapter F6 – Module 41: Food Poisoning (Foodborne Illness)

 

What it is

Food poisoning is an illness caused by eating contaminated food or drinking contaminated water.
It is usually caused by bacteria, viruses, or parasites.

Most cases are short-term, but some can become severe or life-threatening.

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Common Symptoms

Food poisoning mainly affects the stomach and digestive system:

Digestive symptoms

• Diarrhea (watery or sometimes bloody)
• Nausea
• Vomiting
• Stomach cramps
• Abdominal pain

Other symptoms

• Fever
• Headache
• Weakness and fatigue

Dehydration signs (important warning)

• Dry mouth
• Dizziness or lightheadedness
• Reduced or no urination

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Causes of Food Poisoning

Food becomes unsafe when contaminated with harmful organisms:

Main pathogens

• Salmonella
• E. coli
• Campylobacter
• Norovirus
• Listeria

Common sources

• Undercooked meat or poultry
• Raw eggs
• Unwashed fruit and vegetables
• Unpasteurised milk and dairy products
• Contaminated water

How contamination happens

• Poor hand hygiene
• Unsafe food storage
• Food left out too long
• Cross-contamination from surfaces or utensils

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Common Types

• Salmonella – often from poultry and eggs
• E. coli – raw vegetables and undercooked beef
• Norovirus – spreads quickly in groups (schools, cruise ships, care homes)
• Campylobacter – commonly from chicken
• Listeria – found in unpasteurised dairy and deli meats

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Duration

• Symptoms may start within 2–6 hours (some bacteria)
• Or take days to appear depending on infection
• Most cases last 1–2 days
• Some can last up to a week or longer

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Treatment

Most cases improve without hospital treatment.

At home care

• Drink plenty of fluids (hydration is most important)
• Rest
• Eat bland foods (e.g. bananas, rice, toast, applesauce)
• Avoid fatty, spicy, or heavy foods

Medication

• Anti-diarrhoea medicines (e.g. loperamide) only if advised
• Fever or pain relief if needed

Medical attention needed if:

• High fever
• Blood in stool
• Severe abdominal pain
• Signs of dehydration
• Symptoms last more than a few days

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Key Point

Food poisoning is usually short-lived but can become serious quickly if dehydration develops, especially in children, older adults, or people with weakened immune systems.