The ever present plague
The drugs do work
How do drugs stop the flu virus multiplying?
Influenza or “flu” is caused by the influenza virus, and infection with this virus can sometimes be fatal. Hundreds of thousands of people die each year from seasonal flu. A flu pandemic occurs when a new type of influenza virus is introduced to humans from animals and eventually spreads globally.
This activity follows on from the activity 'H-what N-who?' which explains the nomenclature used in naming influenza viruses.
Tamiflu & Relenza are both brand names for the drugs called oseltamivir and zanamavir respectively. They work by inhibiting the action of neuraminidase. Neuraminidase allows release of the virus particles form an infected cell. By preventing this mechanism, the drug stops the virus from spreading to other cells in the body. This is why it is important to take these drugs early on in an infection.
An animation of the mechanism of action of tamiflu can be seen here.
These drugs are currently only recommended to patients in the UK suffering with very severe flu that requires hospitalisation or if they have an underlying condition that puts them at risk. One problem with both of these drugs is the development of resistance against them in certain viral subtypes.
Curriculum links
Science
Applications and implications of science
4a. about the use of contemporary scientific and technological
developments and their benefits, drawbacks and risks
4c. how uncertainties in scientific knowledge and scientific ideas
change over time and about the role of the scientific community in
validating these changes.
Organisms and health
In their study of science, the following should be
covered:
5a. organisms are interdependent and adapted to their
environments
5e human health is affected by a range of environmental and
inherited factors, by the use and misuse of drugs and by medical
treatments.
Scottish Curriculum
Science - Curriculum for Excellence level 4
Body systems and cells - Inheritance: I can use
my understanding of how characteristics are inherited to solve
simple genetic problems and relate this to my understanding of DNA,
genes and chromosomes. SCN 4-14c
Topical Science: I have researched new developments in
science and can explain how their current or future applications
might impact on modern life. SCN 4-20a
Biology National 4 & 5
Potentially relevant to modules: Multicellular
organisms (health), Life on Earth (if adaptation is
part of competition)
Science National 4
Potentially relevant to modules: Human health
(threats to health)
Biology Higher
Potentially relevant to modules: DNA and the
Genome (gene expression),
Human Biology Higher
Potentially relevant to modules: Immunology and Public
health (immune system, control of infectious diseases,
vaccination, public health policy)
The drugs do work
Professor Graeme Laver (1929-2008) and his colleagues were able to show that wild birds were infected with avian influenza and could be an important source of the disease. Before this, scientists thought that birds tended to catch flu from humans and not the other way round.
Read the information from the Summer Science Exhibition in 2006 that describes the importance of this work and how it led on to the development of the most important drugs we have against flu, and watch the video below:
Activity: Draw an image or diagram to show how you think anti-flu drugs stop the flu virus from multiplying in the body.
Tamiflu & Relenza are both brand names for the drugs called oseltamivir and zanamavir respectively. They work by stopping the action of neuraminidase. Neuraminidase is a protein on the surface of the virus that allows release of the virus particles form an infected cell. By preventing the function of this protein, the drug stops the virus from spreading to other cells in the body. This is why it is important to take these drugs early on in an infection.
If you need some help, an animation of the mechanism of action of tamiflu can be seen here.