This lesson is only available to users who have subscribed to the Biology course. Please log in, or click here if you would like to gain access to the full course.
Introduction to the lesson
In the previous lessons we have studied infectious diseases which are ravaging the world's population and claim thousands of lives every year. In this lesson we turn our focus to infectious diseases which have been brought under control or are beginning to be brought under control. The eradication of smallpox is a wonderful example of the success of a vaccination campaign. Measles has not been eradicated and is still one the leading causes of childhood deaths. However, because an effective vaccine for measles has been created, its prevalence is decreasing in developed countries. These two diseases, especially smallpox, begin to point to the disease trend of modern society. In developed countries, due to vaccination, superior health care and good living conditions, infectious diseases are no longer the main health concern and have been taken over by chronic/non-communicable diseases (e.g. stroke, cardiac diseases, diabetes, etc.). This trend is not followed through completely in developing countries, as infectious diseases are still a major cause of concern, but, even in developing countries, chronic diseases are becoming more and more common.
Measles
Read the section "Measles" on p.212 of your text book. Also read the WHO Measles fact sheet.
Learning Activity 1
Answer the following questions in your exercise book.
- What pathogen causes measles?
- What type of pathogen is this?
- Describe the method of transmission
- What is the incubation period?
- Describe the clinical features (symptoms) of measles
- What are some of the complications that may occur?
- Describe the incidence of measles and global distribution of measles
- Why do babies under the age of eight months rarely have measles?
- Why is measles no longer a common childhood disease in developed countries?
- Answer Question 10.15 on p.212.
Smallpox
Smallpox is an example of a devastating disease that has been eradicated worldwide. The text book does not cover smallpox but the syllabus does require you to know something about smallpox.
Learning Activity 2
Answer the following questions in your exercise book. Use the internet or any other resource to help you. You may be interested in this article from the BBC.
- What pathogen(s) caused smallpox?
- What type of pathogen was it?
- What was the method of transmission?
- What was the incubation period?
- What was the site of action of the pathogen?
- What were the clinical features (symptoms)?
- When was smallpox eradicated?
- How was smallpox eradicated?
Summary of infectious diseases
Learning Activity 3
Answer the following questions in your exercise book.
- List some non-infectious diseases you have studied in the course so far
- List the infectious diseases you have studied in this chapter
- Discuss the biological, social and economic factors that need to be considered in the prevention and control of cholera, measles, malaria, TB and HIV /AIDS
- Discuss the factors that influence the global patterns of malaria, TB, and HIV/Aids and assess the importance of these diseases worldwide
- Using your notes and the Coursebook copy and complete the following table:
| Chlora | Malaria | HIV/AIDS | Measles | Smallpox | |
|---|---|---|---|---|---|
| pathogen | |||||
| type of pathogen | |||||
| method of transmission | |||||
| vector | |||||
| incubation period | |||||
| site of action of pathogen | |||||
| clinical features | |||||
| method of diagnosis | |||||
| treatment | |||||
| preventative measures | |||||
| global distribution |
Definitions and review
Mindmap
Add this section to your chapter ten mindmap