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Staying Clean

Endemic: Malaria

An endemic disease is only found in a particular area.

Malaria is an example of an endemic disease (see map) as it can only be caught by a person who has been in the affected area shown in green. So global travel can spread disease by people moving into and out of an endemic area.

the distribution of malaria

Malaria is caused by a single celled micro-organism (protozoan) that enters the body when the female anopheles mosquito bites a human; injecting thousands of pathogens into the blood stream.

The malarial parasite first multiplies rapidly in the liver, they then enter the red blood cells and multiply further.

The symptoms begin with a high fever and enlargement of the liver. Several hours later, this subsides and the infectee gets chills. Every few days this cycle continues. The destruction of red blood cells causes severe anaemia.

Malaria can be controlled by:

  • Destroying the mosquito habitat (bushes)
  • Insecticides in the water where the lavae live
  • Oil on the water creates a small film that suffocates the eggs and prevents future growth.
  • Epidemic: Influenza

    An epidemic is a disease that occurs in a number of cases across an area. Influenza (flu) is an example of this.

    Every few years, there is a nationwide outbreak of influenza, as one of the strains mutates and therefore infects people more severly. Flu is not generally a deadly disease and just causes a week and more of misery. But vulnerable people like the elderly and those with long term illnesses (asmatha, kidney disease) need to be vaccinated every winter as they are more badly affected.


    Personal hygiene is vital in the prevention of community illness. Especially in hospitals where there are a variety of diseases and people who are very vulnerable. And in catering where pathogens such as E-coli can cause food poisoning. There are a variety of methods to reduce infection and improve hygiene.

    Sterilisation is a way of eliminating all micro-organisms, including cells and spores. Heating for 2 minutes at 132oC or using gamma radiation are two ways of doing this.

    Disinfectants kill bacteria, fungi or viruses and are used on inaniamte (not living) surfaces. They may contain oxidants like chlorate (I) and are commercially varied depending on situation.

    Antiseptics rfer to chemicals suitable for use on the skin and wounds. They may contain similar substances to disinfectant but are usually diluted and are often effective against a narrower spectrum of micro-organisms.