Causes and spread of infection
Outcome 1 - Understand the causes of infection
1 - Identify the differences between bacteria, viruses, fungi and parasites
Bacteria - Bacteria are organisms made up of just 1 cell. They are capable of multiplying by themselves, as they have the power to divide. Bacteria exist everywhere, inside and on our bodies. Most of them are completely harmless and some of them are very useful. But some bacteria can cause diseases, either because they end up in the wrong place in the body or simply because they are 'designed' to invade us.
Viruses - Viruses are too small to be seen by the naked eye. They can't multiply on their own, so they have to invade a 'host' cell and take over its machinery in order to be able to make more virus particles. They are capable of latching onto cells and getting inside them.
Fungi - Any of a group of unicellular, multicellular, or syncytial spore-producing organisms feeding on organic matter, including molds, yeast, mushrooms, and toadstools can be either moulds or yeasts. A common yeast infection is thrush, caused by Candida albicans.
Parasites - A parasite is an organism that lives in or on another organism (the host), which damages the host in some way, plus fails to compensate for this damaging by also failing to help the host to an appreciable extent. More narrowly, the term parasite is often used to describe parasitic protozoa, helminths (worms) and arthropods.
2 - Identify common illnesses and infections caused by bacteria, viruses, fungi and parasites.
- Common cold
- Influenza (flu)
- Measles or rubella
- E. Coli
- Athletes foot
3 - Describe what is meant by "infection" and "colonization".
Infections - An