Contemporary VCE BiologySequence 1: Fighting Mosquito Borne Disease ⟩ Module 2:
Contemporary approaches to controlling MBDs
This module will address key knowledge found in VCE Biology Unit 4 by referring to work scientists are doing to combat mosquitoes. This will give students a real-life example and hopefully make the connection between science and society. It is possible that this module could take 2-3 hours of class time.
Summary
VCE Biology (2017-2021)
Unit 4, Area of Study 2, Outcome 2, VCE Biology Study Design
Key knowledge
Biological knowledge and society
- techniques that apply DNA knowledge (specifically gene cloning, genetic screening and DNA profiling) including social and ethical implications of their use (Module 2).
- the distinction between genetically modified and transgenic organisms, their use in agriculture to increase crop productivity and to provide resistance to insect predation and/or disease, and the biological, social and ethical implications that are raised by their use.
- strategies that deal with the emergence of new diseases in a globally connected world (Module 1 and 2), including the distinction between epidemics and pandemics (Sequence 2 Module 1), the use of scientific knowledge to identify the pathogen, and the types of treatments (Module 1 and 2).
Changes in the genetic makeup of a population (Unit 4, Area of Study 1, Outcome 1)
- The manipulation of gene pool through selective breeding programs (Module 2).
Duration
2-3 hours
Student learning outcomes
On completion of this module, students will be able to:
- identify two novel techniques that scientists are exploring and implementing to help combat mosquito borne disease (MBD), A. Wolbachia, B. Sterile insect technique (Oxitec)
- describe tools used to manipulate DNA to control disease
- explain how biological knowledge is applied to biotechnical applications
- explain the interrelationships between scientific knowledge and its application and ethics in society
- understand and analyse contemporary issues in science and technology
Teacher background information
In Module 1, students learned about types of mosquito-borne diseases, how they are transmitted and the current treatment options. This module introduces students to the contemporary science that is being developed to treat mosquitoes (the vector) of mosquito-borne diseases. The two methods that will be introduced are the ‘natural’ Wolbachia method and the genetically modified method developed by Oxitec. This module will address key knowledge found in VCE Biology Unit 4 by referring to work scientists are doing to combat mosquitoes. This will give students a real-life example and hopefully make the connection between science and society. This topic is particularly relevant in society today because MBD affect millions of people in world. Additionally, MBD’s such as the Zika virus is getting heavy media attention around the world.
If you have been working through this resource students have been learning about mosquito-borne diseases and the methods to prevent these diseases e.g. the use of pesticides, life cycle disruption, personal protection. Now we are going to look at how scientific research is trying to combat this problem. As you know by now, there is no vaccine for dengue fever, so scientists within Australia and around the world have been applying some interesting cutting-edge science to address the spread of this disease. Two methods will be studied: the ‘natural’ Wolbachia method, and the Oxitec genetically modified mosquito method. Videos are used to introduce these two strategies for mosquito control.
Teaching sequence
Activities
Activity 2.1 - Video introductions to contemporary approaches to MBD control
Wolbachia videos - Play in order
- Eliminate Dengue: Our challenge
https://vimeo.com/99686346 - Catalyst: This is a great video summarising the Wolbachia project in Australia.
http://www.abc.net.au/catalyst/stories/3786147.htm
Oxitec Videos
- Oxitec’s Eco-Friendly Solution Addresses the Challenges of the Aedes aegypti Mosquito
http://www.oxitec.com/oxitecs-eco-friendly-solution-addresses-challenges-aedes-aegypti-mosquito/ - Can mutant mosquitoes fight Zika and dengue fever?
http://www.pbs.org/video/2365682010/
Teachers may wish to discuss the important ideas at the end of each video or pause the videos at times to highlight important ideas.
In addition to the videos above, teachers may wish to consider using the following:
Activity 2.2 - A comparison of the Wolbachia and Oxitec techniques
Students compare the Wolbachia and Oxitec methods using a variety of resources including newspaper articles, scientific journals, videos and web pages. At least one journal article should be used!
The following questions are to be set by the teacher to direct the students in their research
- If you were a researcher which method would you choose and why?
- Discuss the ethics, approvals and community engagement involved in these methods.
- Why is the organism used in the Wolbachia method not considered to be a genetically modified organism when in the Oxitec method it is?
There is an abundance of information available on the Wolbachia and Oxitec methods as well as on prevention of Zika.
Below is a selection of these resources:
Video
Dengue Fever
Use - A great video for teachers to show to the class to introduce the Wolbachia technique.
Topic - Dengue virus, Vector, Transmission, current control strategies, ethics
The Aedes aegypti mosquito is responsible for spreading the virus between humans. It draws up blood from an infected person, and festers in the mosquito for 12 days. When it bites its victim, the mosquito transfers the virus through its saliva to the next victim. Four hundred years ago, dengue was only found in Africa, but now, with global travel, we see it spread all over the world.
Professors Ritchie and O'Neill, have been working on a way of curbing mosquito populations. They discovered that by injecting mosquitoes with a bacterium called Wolbachia, they could stop the dengue virus from replicating in the insect.
This video explains the overall, Wolbachia technique. There is extra information in this video which describes a blood test for dengue fever.
Video
Dengue Mozzie
Use - Teachers and students
Topic - Dengue virus, Vector, Transmission, current control strategies
Aedes aegypti carries the virus which causes Dengue Fever. This little mosquito and millions like her are responsible for spreading Australia’s worst outbreak of dengue fever on record.
This is the earlier version of the catalyst video listed previously called “Dengue Fever”.
Video
Eliminate Dengue: Our Challenge
Use - Teachers and students: This is one of the essential videos required for this module.
Topic - Dengue virus, Vector, Transmission, current control strategies, community engagement, breeding program
The Eliminate Dengue Program through the World Mosquito Program is developing a new approach to control mosquito-transmitted diseases. We are using naturally occurring bacteria - called Wolbachia - that reduce the ability of mosquitoes to transmit harmful human viruses such as dengue, chikungunya, and Zika. We have shown our approach works when we introduce Wolbachia into mosquitoes in the laboratory, and we have been conducting open trials with dengue-affected communities since 2011.
Video
Microinjection
Use - Teachers and students
Topic - Aedes aegypti, eggs, microinjection
Using microscopic needles, we took Wolbachia from the fruit fly and injected it into young Aedes aegypti mosquito eggs.
Website
World Mosquito Program: Our Research
Use - Teachers and students
Topic - Dengue virus, Vector, Transmission, current control strategies
This provides text information on the Wolbachia technique.
Fact sheet (pdf)
Our Research Overview Fact Sheet
Use - Teacher and students. This is a great handout for teachers to handout to students to give an overview of the Wolbachia project.
Topic - Dengue virus, Vector, Transmission, current control strategies.
The Eliminate Dengue Program through the World Mosquito Program is developing a new approach to control mosquito-transmitted diseases We are using naturally occurring bacteria - called Wolbachia - that reduce the ability of mosquitoes to transmit harmful human viruses such as dengue, chikungunya, and Zika. Following years of research into Wolbachia, our field trials have been met with widespread support from communities, governments and regulators in five countries to date. We are now transforming this groundbreaking approach to make it more affordable and effective for use in at-risk communities around the world. Together, we can protect millions of people and reduce the global burden of mosquito-borne disease
Video
Can mutant mosquitos fight Zika and dengue fever?
Use - A great video for teachers to show to the class. This video can be used to introduce the Oxitec method for controlling mosquito vectors: This is one of the essential videos required for this module.
Topic - Zika virus, genetically engineered mosquitoes, new treatment for mosquito borne disease
As mosquito-borne diseases such as dengue fever and Zika virus continue to ravage Brazil, scientists are racing to fight back. Their latest tactic: genetically engineered mosquitoes that will pass along fatal mutations to their offspring, destroying mosquito populations from within. But some researchers worry our limited knowledge of Zika could throw a wrench into this plan.
Website
Oxitec, Our Solution
Use - Teachers and students: This is the Oxitec website. It explains their project.
Topic - Zika virus, genetically engineered mosquitoes, new treatment for mosquito borne disease
Using advanced genetics and molecular biology Oxitec has developed a new and innovative solution to controlling the dangerous mosquito, Aedes aegypti.
The Oxitec solution harnesses the natural instincts of male mosquitoes to find females in the wild. Oxitec has used genetic engineering to create ‘self-limiting’ male insects which seek out and mate with females. After an Oxitec male mosquito has successfully mated with a wild female, any offspring that result will not survive to adulthood, so the mosquito population declines.
Article
Alphabet’s Verily Joins Zika Fight with Sterile Mosquito Lab
Use - Teachers and students
Topic - Genetically modified mosquitoes, Zika
Alphabet Inc.’s health technology company, Verily Life Sciences LLC, is joining the fight against insect-borne Zika virus by automating the breeding and sorting of sterile mosquitoes that can reduce wild populations.
Video
North Carolina Now
Use - Teachers and students
Topic - Genetic engineering and society
An NCSU program is developing genetically-engineered mosquitoes to reduce transmission of deadly diseases.
Video
Should Genetically Modified Mosquitoes Be Used to Stop the Spread of Zika?
Use - Teachers and Students
Topic - Ethics, Zika, genetically modified mosquitoes
The latest idea from scientists about how to stop the spread of the Zika virus is by reducing populations of its main vector–the Aedes aegypti mosquito–using genetic engineering.
Video
Mutant Mosquitoes in Florida
Use - Students
Topic - Ethics, Zika, genetically modified mosquitoes
The FDA approves a new method for combating disease-carrying mosquitoes.
Article
Genetically Modified Mosquito Sparks a Controversy in Florida
Use - Teachers and students
Topic - Ethics, genetically modified mosquitoes
Officials in the Florida Keys are seeking to use a GM mosquito that could help prevent a recurrence of dengue fever there. But fears among residents – which scientists say are unfounded – are slowing the release of mosquitoes whose offspring are genetically programmed to die.
Article
Ethical, legal and social issues of genetically modifying insect vectors for public health
Use - Teacher reading
Topic - Ethical, social issues, genetically modified mosquitoes
The use of genetically modified (GM) insects for control of human disease can be consistent with common ethical norms of international society to reduce human suffering. This paper considers a range of ethical issues including animal rights, informed consent, community consensus and environmental viewpoints. Each community needs to decide its own priorities for methodology of disease policy guidance for ethical genetic engineering, and to negotiate with neighbouring countries. The approach to genetically modify insects raises few intrinsic ethical issues; however, important environmental and human health concerns need to be assessed before release of any GM insects. The policy that each community adopts should be the product of open dialogue involving all sectors of society. It can be expected that this process will take years and not all communities will endorse genetic control approaches to insect vectors.
Activity
Infectious diseases in the news
Use - Teacher and student section
Topic - Infectious diseases
Newspaper articles are an important resource of science in society. This is an introductory activity which encourages students to begin to use newspapers and magazines to complement their science classes. It is intended to be used early on in the course and will be followed up by more detailed comprehension and critical reading activities later. Infectious disease is suggested as the focus because it is usually taught early in the course and is always in the news.
This activity can be modified to cover the Wolbachia and Oxitec vector control technique.
Activity
Spread of infectious diseases
Use - Teacher and student section
Topic - Spread of infectious diseases
This simple computer model allows students to visualise the spread of an infectious disease and to see how different parameters can affect the rate and extent of the spread. Students can quickly investigate different parameters. Discussion questions link the findings to the real world.
Article (pdf)
Wolbachia and the biological control of mosquito‐borne disease
Use - Teacher and Students
Topic - Wolbachia
This report includes a great figure that explains all aspects of the science to government approval for the Wolbachia project. A great guide for teachers or students.
Iturbe‐Ormaetxe, I., Walker, T., & LO'Neill, S. (2011). Wolbachia and the biological control of mosquito‐borne disease. EMBO reports, 12(6), 508-518.
Figure 1. From the generation of Wolbachia-infected mosquitoes to their release for the control of dengue fever in Australia
Next sequence: Epidemics and Pandemics
