---
title: "Water washed diseases and prevention"
subject: "Water Supply Engineering"
chapter: 4
key: "semester_5/water_supply_engineering:water-washed-diseases"
source: https://www.bctengineer.com/q/semester_5/water_supply_engineering/water-washed-diseases
site: BCT Engineering
---

# Water washed diseases and prevention

Water Supply Engineering · Chapter 4: Quality of Water

- Asked in: 2071 Chaitra, 4 marks; 2079 Bhadra, 2 marks (asked 2 times)
- Video: [Water borne, water based, water washed, water related diseases](https://www.youtube.com/watch?v=VIMZfJh3oH0) — Preventive and Community Medicine Department
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_5/water_supply_engineering/water-washed-diseases
- Whole chapter: https://www.bctengineer.com/md/semester_5/water_supply_engineering/chapter-4

## Question

Describe the types of water washed diseases and their preventive measures.

## Short answer

Water-washed diseases include skin/eye infections (scabies, trachoma), louse-borne diseases (typhus), and faecal-oral diseases (diarrhoea). They are prevented by providing sufficient water (≥20 L/person/day), promoting handwashing with soap, regular bathing, laundry, hygiene education, and sanitation.

## Answer

**Water-washed diseases** are diseases that spread because there is not enough water for personal and domestic hygiene (washing hands, face, body, clothes and utensils). They depend on the quantity of water, not its quality.

#### Types
1. **Diseases of the skin and eyes:** scabies, ringworm, skin sores and ulcers, and eye infections such as trachoma and conjunctivitis. Poor washing allows germs and mites to spread by contact.
2. **Louse-borne diseases:** epidemic typhus and relapsing fever. Lice live and breed in unwashed clothes and hair.
3. **Faecal-oral diseases that washing can prevent:** diarrhoea, dysentery and typhoid also spread by dirty hands when water for handwashing is scarce.

#### Preventive measures
- Provide adequate water in quantity (at least 20 litres per person per day) near the house.
- Promote handwashing with soap after toilet use and before eating, and regular bathing and washing of clothes.
- Provide laundry and bathing places, and tap stands close to the houses.
- Hygiene education and personal cleanliness at schools and health centres.
- Improve sanitation and housing; control lice by regular washing and delousing.
- Treat the infected persons (for example, for trachoma and scabies).

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Water-washed diseases depend mainly on:
   A. the quantity of water available for hygiene
   B. the quality of drinking water
   C. intermediate hosts in water
   D. insects biting near water
   Answer: A. Insufficient water for washing allows them to spread. (Key point: Definition)

2. Which pair is a water-washed disease group?
   A. Cholera and typhoid only
   B. Scabies and trachoma
   C. Malaria and dengue
   D. Schistosomiasis and guinea worm
   Answer: B. Skin and eye infections spread by poor washing. (Key point: Examples)

3. Louse-borne diseases such as epidemic typhus are linked to:
   A. drinking polluted water
   B. snails in ponds
   C. unwashed clothes and hair where lice breed
   D. stagnant water
   Answer: C. Regular washing and delousing controls them. (Key point: Louse-borne)

4. Minimum quantity recommended in the answer is:
   A. 2 litres
   B. 200 litres
   C. 5 m3
   D. 20 litres per person per day
   Answer: D. Adequate water near the house, with soap handwashing. (Key point: Prevention)

## Related in Water Supply Engineering

- [Waterborne diseases, transmission, prevention](https://www.bctengineer.com/question.md?key=semester_5%2Fwater_supply_engineering%3Awater-borne-diseases) — Water Supply Engineering, chapter 4, asked 3×
- [Fecal-oral route and preventive measures](https://www.bctengineer.com/question.md?key=semester_5%2Fwater_supply_engineering%3Afecal-oral-preventive) — Water Supply Engineering, chapter 4
- [Water-based diseases](https://www.bctengineer.com/question.md?key=semester_5%2Fwater_supply_engineering%3Awater-based-diseases-define) — Water Supply Engineering, chapter 4, asked 2×
- [Water vector diseases](https://www.bctengineer.com/question.md?key=semester_5%2Fwater_supply_engineering%3Awater-vector-disease) — Water Supply Engineering, chapter 4

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