Lesson 1

Lesson 2

Lesson 3 & 4

Lesson 5

Lesson 6

Lesson 7

Lesson 8

Lesson 9

• All – Recall keywords

• Most – Describe the different types of pathogen with examples

• Some – Explain how different factors can affect the epidemiology of certain diseases.

2.2.2 Health and Disease

• All – Recall keywords

• Most – Describe the different types of pathogen with examples

• Some – Explain how different factors can affect the epidemiology of certain diseases.

2.2.2 Health and Disease

What is HEALTH?Health is more than simply the absence of disease. It can be defined as your physical, mental and social wellbeing. If you are in good health you are…

•Free from disease

•Able to carry out normal physical and mental tasks

•Well fed, with a balanced diet

•Usually happy, with a positive outlook

•Suitably housed with proper sanitation

•Well integrated into society

Tuberculosis

CholeraChicken Pox

Influenza

MumpsdysenteryAthlete’s

foot

Draw a table with 4 columns showing what type of microbe causes these infectious diseases…

Typhoid

Malaria

HIV

Ring worm

Type of microbe

Bacteria Virus Protozoa Fungus

Infectious disease

Cholera

Tuberculosis

Typhoid

HIV

Mumps

Influenza

Chicken pox

Dysentery

Malaria

Ring worm

Athlete’s foot

Match the key word to the definition1. The rate of occurrence of new cases of a particular

disease in a population being studied2. A branch of medical science that deals with the

incidence, distribution, and control of disease in a population

3. A micro-organism which causes disease4. The total number of cases of a disease in a given

population at a specific time. 5. Anything which impairs the normal functioning of the

body.6. ‘A state of complete physical, mental and social well-

being and not merely the absence of disease of infirmity’ (World Health Organisation)

7. An organism that grows, feeds, and is sheltered on or in a different organism while contributing nothing to the survival of its host, even causing it damage

Incidence, Pathogen, Epidemiology, Parasite, Health, Disease, Prevalence,

Match the key word to the definition

Health: ‘A state of complete physical, mental and social well-being and not merely the absence of disease of infirmity’ (World Health Organisation)

Disease: Anything which impairs the normal functioning of the body.

Pathogen: A micro-organism which causes disease

Parasite: An organism that grows, feeds, and is sheltered on or in a different organism while contributing nothing to the survival of its host, even causing it damage

Epidemiology: a branch of medical science that deals with the incidence, distribution, and control of disease in a population

Prevalence: The total number of cases of a disease in a given population at a specific time.

Incidence: The rate of occurrence of new cases of a particular disease in a population being studied

Tuberculosis

Mycobacterium tuberculosis

DOTs: Directly observed therapy

HIV virus

RNA molecule

Reverse transcriptase

(makes DNA from RNA)

Core

Phospholipid

GlycoproteinEnvelope

5nm

Capsid, made of protein

Malaria

Plasmodium lifecycle

• Zygotes of the parasite undergo a stage of asexual reproduction in the

mosquito’s gut wall

• The parasite returns to the blood and invades the red blood cells

• Here the parasite produces gametes (sexual stage)

• More reproduction within RBCs causes these cells to swell and burst (lysis)

• The mosquito feeds on the blood of a non-infected human

• Anopheles mosquito ingests a blood meal from an infected human

• Plasmodium is transferred from the human to the stomach of the mosquito

• Plasmodium transferred from mosquito to human

• Plasmodium migrate to the human’s liver to undergo asexual reproduction

• Fertilisation occurs

Plasmodium lifecycle

• Anopheles mosquito ingests a blood meal from an infected human

• Plasmodium is transferred from the human to the stomach of the mosquito

• Here the parasite produces gametes (sexual stage)

• Fertilisation occurs

• Zygotes of the parasite undergo a stage of asexual reproduction in the

mosquito’s gut wall

• The mosquito feeds on the blood of a non-infected human

• Plasmodium transferred from mosquito to human

• Plasmodium migrate to the human’s liver to undergo asexual reproduction

• The parasite returns to the blood and invades the red blood cells

• More reproduction within RBCs causes these cells to swell and burst (lysis)

Prophylactics

Prevention is better than a cure!!

Disease Pathogen Method of transmission

Effects on body

Treatment

TB

Malaria

HIV/AIDS

Human immunodefic-

iency virus (retrovirus)

Plasmodium falciparum or

P.virax (protozoa)

Mycobacterium tuberculosis or

M.bovis

Unsafe sex, shared

needles, needle stick

injuries

Airborne droplets,

unpasteurized milk

Anopheles mosquito

vector

Infect lung cells – night sweats, cough, bloody

mucus

Affects immune system (T

lymphocytes) so oppurtunistic

infections take over

Infects red blood cells, results in

fever

Combination therapy to slow viral

replication eg AZT

Antibiotic courses eg.

Streptomycin and rifampin

Prophylactics and

antimalarials eg quinine

Disease Pathogen Method of transmission

Effects on body

Treatment

TB

Malaria

HIV/AIDS

Mycobacterium tuberculosis or

M.bovis

Plasmodium falciparum or

P.virax (protozoa)

Human immunodefic-

iency virus (retrovirus)

Airborne droplets,

unpasteurized milk

Anopheles mosquito

vector

Unsafe sex, shared

needles, needle stick

injuries

Infect lung cells – night sweats, cough, bloody

mucus

Infects red blood cells, results in

fever

Affects immune system (T

lymphocytes) so oppurtunistic

infections take over

Antibiotic courses eg.

Streptomycin and rifampin

Prophylactics and

antimalarials eg quinine

Combination therapy to slow viral

replication eg AZT

Can you explain each of the following trends in epidemiology of disease? (use pg 167 to help if unsure)

1. People who live in crowded conditions are at most risk of contracting TB

2. From the middle of the 19th century the incidence of TB has decreased

3. In the late 1980s there was a dramatic increase of TB in the UK

4. There are certain strains of antibiotic resistant TB emerging