Chemistry

Vaccination: Science versus superstition

This topic presents activities based on vaccinations, ranging from reviewing the vaccination debate to how vaccinations work in our body.

In this topic you will investigate the following:

• How do vaccines work?

• Do all people elect to vaccinate?

• Globally, what effect does this have on communities?

So, let’s inject you with the knowledge you need to make your own decisions!

This is a print version of an interactive online lesson. To sign up for the real thing or for curriculum details about the lesson go to www.cosmosforschools.com

Introduction: Vaccination (P1)

Scientists in the United States have recently completed a study that set out to understand why some people think thatvaccination is dangerous. Their results show that many refuse to believe scientific facts even when they are explained to them.

Vaccines save millions of lives every year. They generally work by introducing a weak or dead pathogen – a virus or germ thatcauses a disease – to a healthy person so that their body can learn what the pathogen looks like and how best to fight it. Beforevaccines were invented, many people died because their bodies didn’t know how to fight some diseases.

Vaccinations can make diseases so rare that they disappear. One of these was smallpox. Doctors think that it killed more than 300million people in the 20 century before finally being eradicated.

So science has proved that vaccines work. But some people refuse to believe that and think vaccines are dangerous. Doctors andscientists worry that if some people won’t use vaccines, not only could they get sick and die, but it will make it hard to makediseases disappear the way smallpox did.

But the study on why some people won’t give their children vaccines shows it is harder to convince people than we thought. Theresearchers found that telling people the scientific evidence about how vaccines work doesn't help if they just don’t believe it.

The report has left scientists scratching their heads wondering how to convince people not just about vaccines but to persuadedoubters about the science on climate change or evolution. Some psychologists say doctors need to talk to individual people andlisten to what’s worrying them. Just telling them the scientific evidence is at best likely to fail, and at worst likely to reinforce theirconcerns.

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Read the full Cosmos Magazine article here

Left: Disease versus vaccine - which is more dangerous? Source: World Health Organization. Right: Anti-vaccinepropaganda. Source: naturalnews.com

Question 1

Propose: Imagine you have been asked to speak with a concerned parent about vaccinating their child. Using the informationabove, suggest what sorts of questions the parent might ask. What advice would you give in return?

Gather: Vaccination (P1)

Video credit: Yootubealator / YouTube.

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Question 1

Define: Explain what is meant by the term pathogen.

Question 2

Vaccines enable the production of memory cells that can helpfight off future attacks from a specific pathogen.

True

False

Question 3

Outline: Describe the body's typical immune response to a pathogen without the use of a vaccine.

Question 4

Research: Recent reports on whooping cough suggest that toddlers need to receive a "booster shot" to prevent possibledevelopment of the infection. Use the internet to find out why some vaccinations require booster shots.

Question 5

Research: Use the Venn diagram below to describe the similarities and differences between a virus and a bacteria.

Question 6

Complete: Choose one of the following vaccines and complete the table below for your chosen vaccine.

Polio vaccine

MMR (measles, mumps, rubella)

DTP (diphtheria, tetanus, pertussis)

Hepatitis B vaccine

Varicella vaccine (chicken pox)

Vaccine chosen Who developed the vaccine? When was the vaccinedeveloped?

Which disease does thisvaccine protect against?

Disease symptoms Who is most susceptible? Is the disease caused by avirus or bacteria?

When and how frequentlyshould a person be

vaccinated?

Question 7

Explain: If a disease has been eradicated why do people still need to be vaccinated against it?

Process: Vaccination (P1)

The message from the World Health Organization for World Immunization Week (24-30 April 2014) is "Immunise for ahealthy future: Know, Check, Protect".

From what we have learned so far, promoting vaccination is a difficult process and there are many organisations and agenciesaround the world working on this. Unfortunately, the decision to vaccinate is not always in the hands of individual citizens.

Not all governments around the world are willing or able to provide the same vaccination opportunities as their rich westerncountries. Deaths from viruses such as HPV (Human Papilloma Virus - the cause of cervical cancer) are occurring at an enormousrate in countries that do not vaccinate against them. Other viruses such as those that cause smallpox, polio or measles have beentargeted in some countries such as India.

Left: A worldwide comparison of cervical cancer deaths. Source: www.womendeliver.org. Right: A "before and after"vaccination snapshot from India. Source: www.jhsph.edu

Question 1

Think: What reasons can you imagine affect whether or not a country develops a vaccination program?

Question 2

Calculate: Use the information about smallpox, polio and measles in India (above) to calculate the percentage decrease in thenumber of reported cases of each disease from before to after the use of vaccines.

Question 3

Research: What is herd immunity and how does it relate to the graphical information above and the vaccination debate?

Question 4

Research: Use the internet to find out what is meant by innate immunity.

Video credit: ABC2 News / YouTube.

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Question 5

Think: How do you think developments such as these will affect vaccination rates around the world? What other designs to the waya vaccine is administered do you think would promote vaccination?

Question 6

Explain: Aside from the vaccination experience being more pleasant, explain how the vaccine band-aid could be considered a moreappropriate method of administering some medications and vaccines.

Hint: What other advantages are described in the video clip?

Receiving a jab from a pointy needle can be bit scary and thethought of it turns a lot of people off receiving vaccinations. Toget around this problem, scientists are working on new andinnovative ways of administering vaccines that are less likely toscare people.

Watch this short clip about a new flu vaccine to see a newapproach!

Apply: Vaccination (P2)

Experiment: Outbreak!

Imgage credit: iStock.

To model the effect of vaccination on the spread of a disease.

We have learned about the how vaccination protects us against pathogens and the process known as herd immunity ensures thesafety of a community. Let's see if we can model the effect of vaccination on the spread of disease. Your teacher has all theresources you need, so follow the instructions below and get ready to find out how susceptible to a disease you might be!

For the teacher: all secret instructions are provided in the model answers attached to these lessons!

Good luck team!

For this experiment, you will need:

A pen or pencil

A card or paper square (supplied by your teacher) with the words "vaccinated" or "not vaccinated" on the top.

0.1M NaOH

Phenolphthalein

Deionised water

Test tubes (one per student)

Test tube racks

Aim

Background

Materials

Part 1 - Before vaccination

1. Your teacher will give you a card with the word 'vaccinated' or ‘not vaccinated’ at the top. Your card is to be kept a secret!

2. You are to move around the room and shake hands with students in the class. Write down the names of four people you haveshaken hands with and return to your seat.

3. Your teacher will have a test tube set up in the room for each of you.

4. Bring your card to the front of the room (don’t reveal it!) and one by one you are to add one drop of phenolphthalein to yourtest tube.

5. If your test tube turns pink, you have contracted a horrible, deadly disease!

6. Those infected students are to remain standing at the front of the room and are assumed to have no immunity to the virusresponsible for the deadly disease.

7. The rest of the class returns to their seat.

8. The infected student(s) are to read out the names of those students they shook hands with. These students stand and revealthe names of those students they shook hands with. This continues until there is no one left seated.

9. Each student reveals if they have been vaccinated or not.

10. Those vaccinated sit down.

11. The students standing represent those infected. Record this number in the results table below.

Part 2 - One quarter of the class is vaccinated

1. Your teacher will redistribute the card and reset the test tubes. Your card is to be kept a secret!

2. Repeat steps 2 - 11 above.

Part 3 - Half of the class is vaccinated

1. Your teacher will redistribute the paper and reset the test tubes. Your card is to be kept a secret!

2. Repeat steps 2 - 11 above.

Part 4 - Three quarters of the class is vaccinated

1. Your teacher will redistribute the paper and reset the test tubes. Your card is to be kept a secret!

2. Repeat steps 2 - 11 above.

Use this data to complete the following questions.

Method

Question 1

Record: Use the table below to present the class results.

Experiment Number of people initiallyinfected

Number of people infected Percentage of populationinfected

Part 1 - Before vaccination 2

Part 2 - One quarter of theclass vaccinated

2

Part 3 - Half of the classvaccinated

2

Part 4 - Three quarters of theclass vaccinated

2

Question 2

Design: Produce a graph that represents the number of people vaccinated against percentage of the population infected. Be sureto include an appropriate title and axis labels (showing units).

Title

X-Axis

auto

Y-A

xis

auto auto auto

Series 1

x y

This graph needs some data!

Question 3

Analyse: What happened to the population as the number of vaccinated people increased?

Question 4

Discuss: As a class, discuss what you think would happen if there were two class members who had an innate immunity to thedisease and did not require a vaccination.

Hint: You may use the class discussion at the bottom of this activity for this question.

Question 5

Conclude: Use this space to respond to your aim and restate your findings.

Hint: Describe what you have learned about vaccination and herd immunity.

Career: Vaccination (P2)

Dr Danielle Stanisic is trying to create the world’s first malaria vaccine.

Danielle Stanisic always wanted to be a doctor. At school, shestudied English, maths, physics, chemistry, and biology in thehopes of getting into medical school. Although she missed outon her dreams of becoming a doctor, Danielle went on to studyscience at university and is now saving lives in a different way.

Malaria is an infectious disease that kills approximately onemillion people each year. There is still no malaria vaccine, butDanielle is trying to change that. She is currently testing one shehas designed to protect people from the disease. As part of thetests, she infects volunteers with malaria parasites afterinjecting them with the vaccine. Clinicians then monitor thevolunteers closely to see if Danielle’s vaccine stops the infectionor not. And as you can imagine, getting the permission todeliberately infect healthy people with a potentially fatal diseaseinvolves a lot of time-consuming paperwork! That’s notsomething Danielle enjoys, but she knows that it is a necessarypart of her otherwise exciting work.

Danielle now works at Griffith University in Queensland, butsays the time she spent working in Papua New Guinea made herrealise how important it is to develop vaccines and determinedto succeed. More than 90% of people in Papua New Guinea areat risk of developing malaria.

Although work keeps her busy, Danielle enjoys scuba diving,travelling, reading and going dragon boating in her spare time.

Question 1

Enquire: Given the opportunity, what questions would you ask Danielle about her research and the work she has done in PapuaNew Guinea?

Cosmos Lessons team

Education Editor: Bill CondieArt director: Robyn AdderlyProfile author: Yi-Di NgLesson authors: Deborah Taylor and Daniel Pikler