Worked example 1
A local village experiences a sudden increase in cholera cases after a flood. Discuss the likely mode of transmission and suggest two ways to control its further spread in the immediate aftermath.
Show solution outline
- Likely Mode of Transmission: Cholera is primarily caused by bacteria (Vibrio cholerae) and is known to spread through contaminated food or water. Following a flood, water sources can easily become contaminated with sewage containing the bacteria from infected individuals, leading to a rapid spread via the indirect route of contaminated water. This scenario describes a localized epidemic.
- Ways to Control Further Spread:
- Providing safe drinking water: Distributing bottled water or ensuring all water is boiled or chlorinated before consumption to eliminate the pathogen. This directly interrupts the transmission route.
- Promoting hand hygiene and sanitation: Educating villagers on the importance of washing hands with soap and clean water, especially after defecation and before handling food. Establishing temporary latrines away from water sources prevents further contamination of the environment.