This introduction covers The Invisible Enemy within Pathogens and Disease Transmission for GCSE Biology. Types of pathogens, how diseases spread, transmission methods, and prevention strategies It is section 1 of 19 in this topic. Use this introduction to connect the idea to the wider topic before moving on to questions and flashcards.
The Invisible Enemy
In 1854, London was gripped by a cholera outbreak that killed over 600 people in just ten days. Dr John Snow suspected contaminated water was the cause, but most scientists believed diseases spread through "bad air." By mapping the cases, Snow identified a water pump on Broad Street as the source. When the pump handle was removed, the outbreak ended. This was one of the first times someone proved that invisible microorganisms - pathogens - could cause disease and spread through specific routes.
Today we know that pathogens are all around us, but understanding how they spread and cause disease allows us to protect ourselves effectively.
Practice questions for Pathogens and Disease Transmission
What is a pathogen?
Explain why viruses need to infect host cells in order to reproduce.