What are Bacterial Diseases in AQA GCSE Biology?
Learn the named bacterial diseases in AQA GCSE Biology: Salmonella food poisoning and gonorrhoea, including their spread, symptoms and control methods.
The two named bacterial diseases studied in AQA GCSE Biology are Salmonella food poisoning and gonorrhoea. You need to know how each disease spreads, its main symptoms and how its spread can be controlled.
This answer assumes AQA GCSE Biology 8461 separate science. This content applies to both Foundation and Higher tiers and is also shared with Combined Science.
Salmonella food poisoning
Salmonella food poisoning is caused by Salmonella bacteria. The bacteria may be ingested in contaminated food or in food prepared under unhygienic conditions.
The bacteria and the toxins they secrete can cause:
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fever
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abdominal cramps
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vomiting
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diarrhoea
Its spread can be reduced by maintaining good food hygiene and cooking food properly. In the UK, poultry are vaccinated against Salmonella to help control its spread.
Gonorrhoea
Gonorrhoea is a sexually transmitted disease caused by a bacterium. It spreads through sexual contact.
Its main symptoms include:
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a thick yellow or green discharge from the vagina or penis
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pain when urinating
The spread of gonorrhoea can be controlled by using barrier methods of contraception, such as condoms, and by treating infected people with antibiotics.
However, many antibiotic-resistant strains have appeared. This means that some antibiotics that previously killed the bacteria may no longer be effective.
Quick comparison
For example, if a question describes illness after eating contaminated poultry, identify Salmonella and link control to food hygiene, thorough cooking or poultry vaccination. If it describes discharge and pain when urinating after sexual contact, identify gonorrhoea and link control to condoms and appropriate antibiotic treatment.
Common exam mistake
Do not confuse bacterial diseases with viral diseases. Antibiotics can treat bacterial infections, but they cannot kill viruses. Also, vaccination is specifically used in poultry to control Salmonella; condoms help prevent the spread of gonorrhoea.
A useful revision check is to remember three points for each disease: cause, transmission and control.
