Disease control, antibiotics and resistance

Last time

Before we start: last time, in The gas exchange system and the alveoli, you learned these points. Here they are again on one card. Keep them in mind, because today builds on them.

Stopping a disease

Once you know how a disease spreads, you know where to cut the chain. Clean water stops cholera. A mosquito net stops malaria. And when someone is already ill with a bacterial disease, an antibiotic may cure them, but only for as long as the antibiotic still works. That last point is why resistance is such a big topic.

Factors that spread disease

Unclean drinking water and poor sewage treatment spread cholera. Poor food hygiene, and flies carrying bacteria from faeces onto food, add to it. Overcrowding, poor housing and malnutrition help T B to spread and to take hold. Warm, wet places with standing water help mosquitoes to breed. Travel and migration carry pathogens between regions, and a lack of vaccination or healthcare lets disease spread unchecked.

Control measures

Cholera is controlled by providing clean drinking water, treating sewage, and food hygiene. Oral rehydration therapy treats the dehydration. T B spreads from person to person, so contact tracing finds and treats people who may have been infected. Pasteurised milk and testing of cattle prevent bovine T B. Malaria is controlled by mosquito nets, insecticides, draining breeding sites and preventive drugs. H I V is controlled by safe sex, screening blood, and clean needles.