People fetching contaminated water. Image credit

People fetching contaminated water. Image credit

ZIMSEC O Level Combined Science Notes: Diseases: Cholera

  • I usually spread by contaminated food and/or water
  • The cholera pathogen is a¬†bacterium called Vibrio cholerae
  • It is an infectious disease
  • The pathogen lives and multiplies in the digestive system


  • Acute diarrhoea
  • Fever
  • Vomiting
  • Leading to dehydration and in some cases death within 24 hours
  • Effects are acute in children and infants


  • Oral rehydration (using salt and sugar solution)
  • Using Antibiotics

Prevention and control

  • Good sanitation
  • Protection of water sources such as water wells
  • Vaccination especially when one is visiting a contaminated area
  • Isolation of infected persons
  • Using water treatment chemicals
  • Practising good hygiene


  • Good hygiene can be used to prevent diseases like cholera
  • Many such diseases are spread by vectors such as flies
  • Hygiene can be personal/individual, domestic or community

Personal hygiene

  • This is at an individual level
  • Includes good habits such as having meals regularly, having enough sleep and stress prevention
  • Washing of hands after using the toilet
  • Covering your mouth while sneezing etc

Domestic hygiene

  • When the whole household takes part
  • Includes proper handling, storage and preparation of water and food to prevent contamination

Community hygiene

  • Is necessary to prevent epidemics such as cholera
  • It might include:
  • proper water treatment
  • Proper sewage disposal
  • Proper ante and post natal care
  • Immunising children
  • Control of vectors such as mosquitos
  • Building sufficient and adequate health facilities

To access more topics go to the Combined Science Notes page