In this short film Dr Michael Mosley describes the infection of household cats with Toxoplasma gondii.
This infection starts with growing cysts in an infected cat. These are excreted and can survive for a long period outside a host. They are eventually accidentally eaten by mice or rats. To complete its life-cycle the parasite must return to a cat.
Michael Mosley interviews a scientist called Joanne Webster who describes her experiment which showed that infected rats have drastically altered behaviours. This includes being attracted to cat urine (not repelled by it).
This makes it easier for the rat to be caught and the parasite to complete its life-cycle.
Amazingly about a quarter of the UK population is infected with this disease.
Evidence suggests that infection may also affect our behaviour.
This short film is from the BBC series, Michael Mosley: Infested! Living with parasites.
Teacher Notes
This short film could provide an interesting introduction to parasitism (and mutualism).
This might lead onto studying the effects of parasites on humans or other organisms, including plants.
Examples could include the suppression of coagulants in malaria-infected mosquitoes and the manipulation of hormones that sacculina causes in host grabs.
The selective disadvantage which infected rats have could also introduce the topic of evolution.
Curriculum Notes
This short film is suitable for teaching biology at KS4/GCSE in England, Wales and Northern Ireland and National 4/5 in Scotland.
More from Michael Mosley: Infested! Living with Parasites:
Infested by hookworm. video
In this short film Dr Michael Mosley investigates hookworms - large parasites which invade our immune system. He meets a sufferer of Crohn’s disease who infected himself with hookworms to reduce his symptoms.
Infested by leeches. video
In this short film Dr Michael Mosley interviews a surgeon who is pioneering the use of leeches in medical research.
Infested by lice. video
In this short film Dr Michael Mosley visits a 'delousing salon' in London to collect live head lice.
Infested by tapeworms. video
In this short film Dr Michael Mosley visits Kenya to see how the beef tapeworm needs to infect both beef cattle and humans to complete its life-cycle.
Infested with malaria. video
In this short film Dr Michael Mosley investigates the parasite Plasmodium that carries malaria. This disease kills more than half a million people per year.
