5.6 - Preventing the Spread of Disease

Reducing disease spread through hygiene, food and water

• Communicable (infectious) diseases are caused by pathogens that pass from one person to another.
• They can be reduced - and sometimes stopped altogether - by breaking the routes along which they spread.
• One group of measures works by keeping people, their food, and their water free of pathogens.

Key measures

• Good hygiene - Simple measures stop pathogens passing between people, e.g. washing hands thoroughly before preparing food and after sneezing or using the toilet. Cleaning a wound kills microorganisms near it and stops them entering the blood.
• Hygienic food preparation - Preparing food in clean conditions stops pathogens spreading from work surfaces, chopping boards, and hands onto food. Cooking food thoroughly kills bacteria such as those that cause food poisoning.
• A clean water supply - Access to clean, fresh water for drinking and cooking reduces the spread of water-borne pathogens, otherwise picked up by drinking or bathing in dirty water.
• Safe waste disposal and sewage treatment - Not letting rubbish build up, safely disposing of items such as soiled bandages and used needles, and treating sewage so it can't contaminate drinking water all cut the spread of pathogens carried in human waste.

Reduce disease spread - Vectors, isolation, vaccination

These measures reduce the spread of disease by attacking what carries a pathogen and by keeping infected individuals apart from others.

Destroying vectors

• Getting rid of the organisms that carry a pathogen prevents it being passed on.
• Insect vectors can be killed with insecticides, or their breeding habitats removed so they can no longer multiply.
• For a disease spread by mosquitoes, nets and insect repellent also stop people being bitten.

Isolating infected individuals

• Keeping a person (or, on a farm, an infected animal) away from others prevents them passing the disease on.
• In some cases, restricting travel stops it spreading further afield.
• Detecting and treating a disease early also limits how far it spreads.

Vaccination

• Vaccinating people and animals against a communicable disease means they are less likely to develop the infection and then pass it on.
• This reduces how far the disease spreads through a population, as shown below.