Outbreak. Lesson aim. Lesson objectives. Lesson Outcomes. Running the Session(s) Curriculum links. Time required

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1 Key Stage 4 LeSSon plan 2 - outbreak Outbreak Lesson aim To familiarise students with the way in which a contagious disease can spread through a dense population and the measures which can be taken to mitigate this spread. 4 Lesson objectives Students will be expected to: Work effectively within a group. Discuss within a group. Communicate effectively with others. Understand that there are a range of different factors affecting how a disease spreads through a population. Lesson Outcomes By the end of this lesson: All students must be able to appreciate that growing bacteria in culture is part of the process of diagnosis and treatment of infections. Most students should be able to appreciate that there are a range of ways, beyond just medicine, in which the spread of disease can be stopped. Some students may be able to appreciate that for a disease to become epidemic or even pandemic is quite difficult and a large number of factors have to be just right in order for it to happen. Curriculum links KS4 Science Practical & enquiry skills: 2a-d Communication skills: 3c Applications & implications: 4a, b Organisms & health: 5e Time required One hour for the initial session. Running the Session(s) This activity can be run as a single session in the science lab in one lesson. However, there is an optional Extended Activity which can be added to the lesson which involves running a whole school activity. This option will require some detailed pre-preparation and involvement of students outside of their normal lessons. Information and supporting resources for this extension activity are given in the Extended Activity section at the end of this lesson plan. If circumstances do not allow a whole school activity, the Extended Activity can also be run for just one year group. 1

2 Key Stage 4 Lesson plan 2 - outbreak Pre-Lesson preparation required If possible, arrange tables so that students can work in separate pairs. For the first part of the lesson there should be adequate space for students to move from one side of the room to the other safely. Each pair of students will need access to 4 pre-prepared Petri dishes for the purpose of preparing bacterial cultures. A sample of a suitable bacterial culture will also need to be provided for the students. Each pair of students will also require a test tube rack with four labelled test tubes containing a few millilitres of the following solutions: Undiluted antiseptic liquid ( Detol, Milton fluid etc.) Diluted antiseptic liquid (approx 20 parts de-ionised water to 1 part antiseptic) De-ionised water Glucose solution These samples will need to be labelled Test Antibiotic A, B, C, D respectively. Explain that these are experimental medicines and are still being tested to see how human beings will react to them. Students must not attempt to taste them. Materials and equipment required For the students (per pair) 4 sterile Petri dishes containing agar jelly Wire loop Bunsen burner 4 pipettes Test tube rack containing a set of four solutions as described above A sample of a suitable bacterial culture Safety goggles 1 copy of Student Resource Sheet 5.1 Testing Bacteria 2 copies (1 per student) of: Student Resource Sheet 5.2 Spreading Diseases Student Resource Sheet 5.3 Who s Who in Epidemic Management? Note: It is quite possible that students will not have time to complete Student Resource Sheet 5.2 during the lesson. Even if the tasks are not completed Student Resource Sheets 5.2 and 5.3 provide useful background information on epidemic propagation and the UK strategy for epidemic management. Prior knowledge required Students should be aware that many human diseases are spread by bacteria and viruses. 2

3 Key Stage 4 LeSSon plan 2 - outbreak Lesson structure (including approximate timings) Housekeeping: Intro. Activity: Introduction of lesson and explanation of aims and objectives. Arrange students into pairs and ensure that bags and coats are safely stowed out of the way. (3 minutes) The CD-ROM which accompanies this pack includes a starter activity for this lesson. It can be accessed by opening the CD in Windows Explorer and the double clicking the file Outbreak Starter Activity. This file is a Microsoft Powerpoint based activity and is designed to be run using an interactive whiteboard. The activity is based around a series of quick questions designed to reinforce what students should already know about bacteria and viruses. For each question two possible answers are given and each answer corresponds with either the left side of the room or the right side of the room. To signify their answer, each student goes to the side of the room that corresponds with that answer. There should be no running. Some students may be self conscious about moving around the room so an alternative way of carrying this activity out is to give each student two different coloured pieces of card with which to indicate their answers. This simple and quick activity is designed to focus students attention on the lesson subject and refresh topic knowledge. (10 minutes) Group Discussion: Use the introductory activity to develop a discussion about the relationship between disease and bacteria and viruses. Ask students to consider how science allows us to treat diseases caused by bacteria and viruses. They should come up with ideas about medicine, antibiotics and vaccination. Ask students how we know what medicines to use. This should lead them to realise that in order to use the appropriate medicine we must know what bacteria or virus we are actually dealing with. Lead this part of the discussion into a brief description of the role of a clinical microbiologist in identifying bacterial, viral, fungal and parasitic infections and the role of the biomedical scientist in carrying out tests to assist doctors in the diagnosis and treatment of disease. A more detailed description of these roles is given on Student Resource Sheet 5.3 Who s Who in Epidemic Management? Briefly review the role of antibiotics and vaccinations in the fight against disease. (15 minutes) Group Activity: Set the scenario that, working in their pairs, students are biomedical scientists and they are conducting tests on an unknown strain of bacteria. They have four different antibiotics which are still undergoing trials and they need to see which is going to be the most effective against this particular bacterium. Student Resource Sheet 5.1 Testing Bacteria will guide them through the process. Safety instructions on culturing bacteria are included on this sheet but it is important that these be reinforced before students start the activity. It will be useful to point out here that viruses cannot be treated with antibiotics and that they cannot be grown in a culture in this way as they require live cells in which to reproduce. The completed cultures will need to be incubated so that students can examine them in the next lesson. (24 minutes) 3

4 Key Stage 4 Lesson plan 2 - outbreak Class Discussion: In their pairs give students one minute to consider the different ways in which a disease might spread through a population. Ask for examples. The main ones to consider are: Closing: Touch passed directly from person to person or via a third party such as a door handle etc. This category can include sexual contact. Airborne passed through airborne droplets expelled through sneezing or coughing. Vector or vehicle some diseases, such as malaria, are passed on by an insect carrier or vector. Others can be transmitted through food or water which acts as a vehicle for disease transmission. Explain the terms pandemic and epidemic. Students should then be able to complete the task on Student Resource Sheet 5.2 Spreading Diseases either for homework or as extension work within the lesson if time allows. The task on this sheet encourages them to consider how different methods of disease propagation could be reduced or stopped. Student Resource Sheet 5.3 Who s Who in Epidemic Management? provides supporting information on how the UK process for epidemic management works. (5 minutes) Summarise key points: In order to treat diseases healthcare scientists need to first identify them. Producing bacterial cultures is one way of doing this. Diseases are spread in a number of different ways. There are a number of different ways beyond just medicine in which the spread of disease can be stopped. End. (3 minutes) Extension/Homework More able students might be asked to consider why some diseases kill their hosts. They should consider if there might be any evolutionary advantages in doing this or do all pathogens evolve to a state where they are able to live within their host without killing it? Follow Up If you are not running the Extended Activity students will need to examine their cultures at the beginning of the next lesson. It should be obvious which antibiotic has been most effective. Cultures should be placed in an autoclave and destroyed after this. Differentiation Adapt discussion sessions to suit ability and age group. Provide extra support during group activity for those students who require it. Risk assessment It is the responsibility of the supervising teacher to carry out all risk assessments with regard to this activity and to make sure that any such risk assessment complies with the requirements of the particular institution in which it is being conducted. 4

5 Key Stage 4 LeSSon plan 2 - outbreak Extended Activity The Extended Activity is designed to run for one day across the whole school. It can involve the whole school population or can be restricted to one year group. Either way, it will involve the group who participated in the original lesson and will involve a significant level of preparation. The Extended Activity will need to follow on several days after the initial lesson. Teachers running this activity may also wish to restrict the running of the activity to break times to avoid potential disruption in lessons as students distribute disease cards. It should be noted that this will make the activity less effective. Pre-Preparation A day or two prior to the activity the students will need to revisit their bacterial cultures. They will need to assess which sample has proved the most effective antibiotic as this is the antibiotic which will be issued at the medication stations. Students can be asked to help with the reproduction of disease cards and other materials needed for the exercise. It is suggested that students produce a simple leaflet for issue to all students in the school, explaining the rules for the activity. Students from the group can be used to run the vaccination and medication stations during the activity. Outline of the Activity During a break time on the day previous to the activity a vaccination post can be set up somewhere in the school. It will be open to all but there will be a limited number of vaccines (enough to cover about 20% of the school population) and essential personnel such as teachers and prefects etc should have first priority in receiving a vaccination. The vaccination will take the form of a coloured card. The cards should be available in red and orange in approximately a 3 to 1 mix of red to orange. The more abundant red represents a successful vaccination and the other an ineffective vaccination. People being vaccinated should not be told what the colours mean. On the morning of the activity four or five students from the original group will be designated as disease carriers. Between them they will be given enough Disease Cards to cover every student and teacher in the school. As soon as they enter school premises they must start handing these cards out in bundles of 20. The cards need to be handed to roughly one in three of the students and teachers who come within arms reach of these carriers. They must ensure that they keep a card for themselves. Copies of disease cards and vaccination cards are printed on the inside back cover of this Teachers Notes book for photocopying. Alternatively, they may be printed out directly from the relevant files on the CD-ROM included with this pack. Each of these second generation disease carriers must keep one card for themselves and then hand them out in bundles of four or five again to roughly one in three of the students or teachers who come within arms reach. These third generation disease carriers must again keep one card for themselves and hand the rest out, one by one, according to the same criteria. During morning break one or two medication stations can be opened around the school. These will be able to issue antibiotics in the form of rubber stamps. The stamps can simply be rubber date stamps as used in the library and are made directly onto the disease cards. For best effect the activity will need to be completed with a whole school assembly. If this is not possible year group assemblies should be held. 5

6 Key Stage 4 Lesson plan 2 - outbreak Ending the Activity At the final assembly ask all students and staff to stand. Ask students then to sit down according to the following criteria and in the following order. It will also be useful for someone to take a note of numbers. 1. Any student with a disease card with the number 4 on it even if they have received a vaccination and/or antibiotics. Disease card 4 represents the disease in its most powerful form. Unfortunately these students didn t make it. 2. Any student with a disease card with the number 3 on it and no vaccination card. It doesn t matter if they received antibiotics or not. Unfortunately these students didn t make it. 3. Any student with a disease card with the number 3 on it and an orange vaccination card. It doesn t matter if they received antibiotics or not. Unfortunately these students didn t make it. 4. Any student with the disease card number 2 who has neither a vaccination card nor antibiotic stamp. 5. Any student with the disease card number 2 with an orange vaccination card and no antibiotic stamp. Disease card number 1 represented a weak form of the disease which was not fatal. All other students can remain standing. The students left standing at the end of this process have survived the initial outbreak. It should be pointed out that epidemics often occur in a series of waves where the first wave of disease is not necessarily the most virulent. It is suggested that the above criteria are projected onto a screen as they are being addressed. This activity should graphically illustrate how a highly contagious disease could spread through a dense population. The contagious nature of this simulated disease has been exaggerated for the purposes of the exercise. 6

7 Disease and Vaccination Cards