Transcript Eradication of diseases

Eradication of Diseases
Valeria Wrigglesworth
Chesterfield College
Topic
Eradication of Diseases
Aims
 To teach the topic of eradication of diseases
Level
Level 3
Method
Slide 2 to 6 for teacher only. Slide 16 – 18 Tasks, Slide 21 –
Task, Slide 22 – Task, Slide 25 -27 blank worksheets for
students
Equipment
 Hand-outs
 Pens/pencils
 Plain paper either A3 or A4
Duration
>30 Minutes
Lesson Plan
(for Teacher’s eyes only)
• Aim
– Evaluate the effects of mass immunisation programmes using examples
of smallpox, measles, tuberculosis, cholera and malaria
• Learning Outcomes:
– Students will be able to:
• Describe some basic facts associated with smallpox, measles, tuberculosis,
cholera and malaria
• Analyse the reasons for the differences in the success of eradicating these
diseases through vaccination.
Lesson Plan
(for Teacher’s eyes only)
• Individual Learner Needs and Use of Differentiated
Activities
– Small group task 1:
• The students can opt out of looking at the images associated with
the diseases if they feel uneasy about this part of the task. This
activity will particularly benefit the students with visual and
kinaesthetic learning styles
Lesson Plan
Time
LO: 1
0-7
min
(for Teacher’s eyes only)
Method / Activity
Resources
Learning Checks
Introduction of the LOs
PPT slide
Small group work 1
The students match the name of each disease
(measles; smallpox; TB; cholera; malaria) to a card
containing general information about a diseases and
an image associated with each disease.
Per group:
A table containing the names of the
diseases; a set of laminated
information cards; a set of image
cards
Students’ progress is monitored;
Answer check;
Q&A
PPT ‘Eradication of diseases’
Q&A
E&D:
The students can opt out of looking at the images
associated with the diseases if they feel uneasy
about this part of the task.
LO: 2
7-10
min
The students asked to suggest which of the five
diseases:

Has already been eradicated.

Has the highest number of infected people
worldwide (per year).

Has the highest mortality rate worldwide (per
year).
Maths: Students need to be able to rank the
diseases in terms of the numbers of people affected
Answer check using PPT slide
Lesson Plan
(for Teacher’s eyes only)
Time
Method / Activity
LO: 2
The students are given the reasons of the
successful eradication of smallpox on the
PPT slide.
10-25
min
Resources
Learning Checks
Small group work 2
Students analyse an information sheet about Information handouts;
one of the four diseases (measles; TB;
PPT slide ‘reasons for
cholera; malaria). Students are asked to list 2 eradication of smallpox’
or more reasons why this disease has not
been eradicated yet. Students exchange
information in a Q&A session.
Literacy: the students need to be able to
analyse information and summarise the
relevant facts; be able to understand and use LOs PPT slide
appropriate terminology.
LOs check – Q&A
Handout with the summary of information on
the five diseases is distributed for the
students to use at home.
Handout with the summary
table.
Students’ progress is monitored;
Q&A
Q&A
Cholera
Cholera is an acute diarrhoeal infection caused by ingestion of food or water contaminated with the
bacterium Vibrio cholerae.
Cholera is a highly infectious disease. It affects both children and adults and can potentially kill within
hours.
About 75% of people infected with V. cholerae do not develop any symptoms, although the bacteria
are present in their faeces for 7–14 days after infection and are shed back into the environment,
potentially infecting other people.
Cholera transmission is closely linked to inadequate environmental management. Typical at-risk areas
include urban slums, where basic infrastructure is not available, as well as camps for displaced people
or refugees, where minimum requirements of clean water and sanitation are not met.
The bacterium causing cholera which can live in the intestines where antibodies - produced by
vaccines that are injected - cannot get to it. A type of oral cholera vaccine has recently been developed
that can provide short-term protection for up to 6 months following immunization.
Malaria
Malaria is caused by a parasite called Plasmodium, which is transmitted via the bites of infected
mosquitoes. In the human body, the parasites multiply in the liver, and then infect red blood cells.
Malaria is transmitted by mosquitoes that respect no borders. The parasite carried by mosquitoes is
continually evolving resistance to the latest pharmaceuticals. For example, antimalarial medicines
such as chloroquine and sulfadoxine-pyrimethamine, which were successfully used in 1970s and
1980s, stopped being effective in killing Plasmodium.
Human immunity is another important factor. Partial immunity developed over years of exposure does
reduce the risk of contracting malaria however it never provides complete protection.
Malaria is preventable and curable. In theory, all you need to stop mosquitoes from transmitting the
malaria parasite are insecticide-treated bed-nets, and all you need to reduce the reservoir of infectious
human carriers is a course of pills costing less than £5.
There are currently no licensed vaccines against malaria or any other human parasite.
Measles
Measles is a highly contagious, serious disease caused by a virus. The virus is spread by coughing
and sneezing, close personal contact or direct contact with infected nasal or throat secretions. The
disease is characterised by a high fever, a rash and generally feeling unwell. Measles is one of the
leading causes of death among young children even though a safe and cost-effective vaccine is
available.
Measles is the single most infectious disease known. To eliminate it, you need >95% of the population
vaccinated. A poor response to the vaccine has been shown by some children, who need boosters. In
2011, about 84% of the world's children received one dose of measles vaccine by their first birthday
through routine health services.
No specific antiviral treatment exists for measles virus.
In 1998, a study published in the respected journal The Lancet raised the possibility that the MMR jab
that provides immunity form measles may be linked to autism and bowel disease. This prompted
many parents in the UK to decide against having their children vaccinated with the MMR jab. This
resulted in the recent outbreak in Wales, with 800 cases and one death recorded.
Smallpox
Smallpox was caused by a virola virus and was transmitted between people through the air. It was
usually spread by face-to face contact with an infected person and to a lesser extent through
contaminated clothes and bedding.
Once a person contracted the disease, he or she remained apparently healthy and non-infectious for
up to 17 days. But the onset of flulike symptoms heralded the infectious stage, leading after two or
three days to a reduction in fever but to the appearance of the characteristic rash 0 first on the face,
then on the hand, forearms and trunk. Ulcerating lesion formed in the nose, releasing large of
amounts of the virus into the throat.
Nearly one third of those who contacted the major died from it, and most of those who survived – up to
80 percent, were left with deeply potted marks, especially on the face. Many were left blind. In 1700s
Europe, once third of all cases of blindness where attributed to smallpox
Tuberculosis (TB)
This disease was once thought to have been eradicated, but is actually showing a resurgence. Tuberculosis
(TB) is second only to HIV/AIDS as the greatest killer worldwide due to a single infectious agent.
Tuberculosis is an infectious bacterial disease caused by Mycobacterium tuberculosis, which most
commonly affects the lungs. It is transmitted from person to person via droplets from the throat and lungs of
people with the active TB. In healthy people, infection with Mycobacterium tuberculosis often causes no
symptoms, since the person's immune system acts to “wall off” the bacteria. Poor housing and homelessness
lowers peoples' natural resistance. Symptoms of active TB of the lung are coughing, sometimes with sputum
or blood, chest pains, weakness, weight loss, fever and night sweats.
It can be carried in cattle.
Diagnosing TB can be difficult, particularly in children. A new two-hour test that has proven to be effective in
diagnosing TB and the presence of drug resistance is now being rolled-out in many countries.
Tuberculosis is treatable with a six-month course of antibiotics. However, some TB bacteria are resistant to
drugs used to treat them because they can mutate.
Disease Table
Information card
Measles
Most likely among poorly nourished young
children.
A runny nose, a cough, red and watery eyes,
and small white spots inside the cheeks can
develop in the initial stage. After several days,
a rash erupts, usually on the face and upper
neck.
The most serious complications include
blindness, encephalitis (an infection that
causes the brain swelling), severe diarrhoea
and dehydration.
Information card
Cholera
Picture card
Acute intestinal infection caused by ingestion of
the bacterium.
Bacterium produces a toxin that causes watery
diarrhoea that can quickly lead to severe
dehydration and death if treatment is not promptly
given. Vomiting also occurs in most patients .
Picture card
Disease Table
continued
Information card
Malaria
Caused by a type of microscopic parasite
called Plasmodium.
The first symptoms – fever, headache, chills
and vomiting – may be mild and difficult to
diagnose.
However, if not treated within 24 hours, can
progress to severe illness often leading to
death.
Symptoms can include severe anaemia,
respiratory distress. Multi-organ
problems/failures can occur in severe cases.
Information card
Tuberculosis
Picture card
About one-third of the world’s population has
latent form of the disease, which means people
have been infected by the bacteria but are not ill
with disease and cannot transmit it.
Common symptoms of active form of the disease
are: cough with blood at times, chest pains,
weakness, weight loss, fever and night sweats.
Mild/less infections forms of the disease are often
difficult to diagnose.
Picture card
Disease Table
continued
Information card
Smallpox
Caused by a virus. Early symptoms include
high fever and fatigue.
The virus produces a characteristic rash,
particularly on the face, arms and legs. The
resulting spots become filled with clear fluid
and later, pus, and then form a crust, which
eventually dries up and falls off.
Fatal in up to 30% of cases.
Picture card
By the end of this session the
students should be able to:
• Describe some basic facts associated with some common infectious
diseases:
–
–
–
–
–
Smallpox
Measles
Tuberculosis
Cholera
Malaria
• Analyse the reasons for the differences in the success of eradicating
these diseases through immunisation.
Task 1
Name of the disease
Work in
small
groups (2-3)
Information card
containing facts about the
disease
Image associated the
disease
(optional)
Task 1
continued
Name of the disease
Information card
containing facts about the
disease
Image associated the
disease
(optional)
Task 1
continued
Name of the disease
Information card
containing facts about the
disease
Image associated the
disease
(optional)
Numbers of People Affected
Disease
Cases worldwide in 2011
Deaths worldwide in
2011
Smallpox
None
Last case reported in 1978
None
Cholera
200 000
5000
Measles
20 million
160 000
Malaria
300-500 million
700 000
Tuberculosis
9 million
1.6 million
Source: World Health Organization (WHO)
Reasons for successful
eradication of smallpox
• The disease was passed directly between people (no animal / insect
carriers)
• Easy to diagnose due to distinctive rash
• Long time between contracting it and becoming infectious
• Survivors gained lifetime immunity
• To eliminate smallpox >66% of the population needed to be
vaccinated.
Task 2
Suggest which of these diseases:
•
Has already been eradicated via immunisation?
•
Has the highest number of infected people worldwide (per year)?
•
Has the highest mortality rate worldwide (per year)?
Task 3
–
work in small groups (2-3)
• Read about a particular disease.
• Suggest some key reasons why this disease has not been eradicated
yet.
By the end of this session you
should be able to
• Describe some basic facts associated with smallpox, measles,
tuberculosis, cholera and malaria.
• Analyse the reasons for the differences in the success of eradicating
these diseases through vaccination.
Extensions
• List the methods by which the diseases they just learned about
spread;
• Suggest other methods by which diseases could be spread;
• Suggest which method of spreading would make the disease more
difficult to eradicate; quicker to infect large numbers of people.
• Choose a current UK immunisation programme and evaluate its
effects on individuals and the wider community.
Student Work Sheets
Notes
Student Work Sheets
Notes
Student Work Sheets
Notes
For further information please contact The STEM Alliance
[email protected] or visit www.STEMalliance.uk