2. Overview Many countries have adopted the slogan of " health is wealth". A nation that invests in the health of its populace does so with the clear understanding that the rewards will enhance the progress of that nation. Simple every day diseases like malaria and measles which, affect people in many tropical countries have received special attention from governments. The now dreadful disease, AIDS, has become a global concern. The fight against AIDS takes place both in developed and developing countries.

3. Purpose The reality of the disease AIDS must be underscored in every country. The purpose of this lesson is to show what efforts are being undertaken to conquer the disease and how it can be prevented in many societies.

4. Objectives Students will be able to:

i. Identify the common diseases in a given community
ii. Discuss control measures in health care delivery
iii. Distinguish between HIV and AIDS
iv. Explain how AIDS is spread
v. Discuss how the spread of AIDS can be reduced.

5. Resources/materials

• Several illustrations/pictures of people, especially children, who are infected with various diseases.
• Charts showing how certain common diseases are transmitted.

6. Activities and Procedures The teacher should start this lesson by exploring with the children what is really meant by Health. The opposite of health is unhealthy. Diseases play an important role in making people unhealthy. Many diseases such as colds, measles, malaria and diarrhoea are caused by PATHOGENS. Pathogens are micro-organisms which make people ill. Any organism which causes a disease is called a pathogen.

Not all diseases are caused by pathogens. There are other causes of diseases. The teacher should discuss the following causes of disease:

• Chemicals and poisons
• Poor nutrition
• Genetic defects

The spread of disease is an important aspect to discuss. Diseases can be spread in many ways. The following ways by which diseases are spread should first be discussed:

i. Close contact
ii. Food
iii. Air
iv. Water
v. Vectors-animals such as mosquitoes and flies, which can carry pathogens.

At this stage, common diseases in the community should be discussed.

Attention in this lesson should now shift to Sexually Transmitted Diseases [STD]. Great care must be exercised in discussing this aspect of the lesson. Sexually Transmitted Diseases are a group of diseases which are spread by a special form of contact-sexual contact during sexual intercourse. The teacher should discuss a few:

• Gonorrhoea
• Syphilis
• Herpes.

It is usually a good practice for the teacher to arrange with a health specialist to come to the school to give the talks on STDs. The teacher should not lose sight of the moral aspects when discussing the above diseases.

As of today, the spread of the disease AIDS has been mentioned in many parts of the world. Students should be well informed about the myths and facts of the disease called AIDS. The clear distinction between HIV and AIDS should be explained to the students. The ways through which AIDS can be spread should be discussed. It is important that students should be told about the dangers of contracting AIDS not only to themselves but also to the nation. Finally, the teacher should reassure the students that AIDS is not spread by mosquitoes, as some people erroneously believe. The prevention of AIDS should be discussed.

7. Tying it all together The teacher should use this opportunity to make reference to previous lessons, which touch on health:

• Personal hygiene
• Care of the environment.

The slogan "Health is wealth" should re-echo in this lesson. A hospital visit should be arranged for the students if possible.

8. Assessment The teacher should work out a scheme whereby a Record of the Health of the class is kept.

9. Author(s) S. T. Bajah stan@alpha.linkserve.com

10. References Ministry of Education and Culture (2000). Step Ahead New Secondary Science Student's Book 2 Zimsci Harare: Longman Zimbabwe (Pvt) Ltd.

Bajah, S. T. et al.(2000) AIDS: the wicked disease Lagos: CSS Limited.