WATER & DISEASES
Murray BiedlerJuly 09, 2012
Current Medical Reality
Disease Morbidity (episodes/year)
Mortality (deaths/year)
Diarrhoeal diseases
1,000,000,000 3,300,000
Intestinal worms 1,500,000,000 100,000
Shistosomiasis 200,000,000 200,000
Malaria 400,000,000 1,500,000
Total burden/year 3,100,000,000 5,000,000
F-DIAGRAM: TRANSMISSION ROUTES
WATER-RELATED DISEASES
ENVIRONMENTAL CLASSIFICATIONS
Faecal-Oral Water-Washed Water-Based Water-Related Vectors
Faecal-Oral Diseases Pathogens transmitted by human
excreta and then ingested Infections of intestinal tract
(diarrhoea) - illness & death Personal & domestic hygiene important
PRIMARY
WATER & FOOD BORNE
TRANSMISSION
SECONDARY FAECAL-ORAL
TRANSMISSION
Environmental vibrion reservoir
Transmision routesCholera
Faecal-Oral DiseasesDiarrhoeas & Dysenteries Amoebic Cholera E.Coli Shigellosis
Enteric Fevers
Typhoid
Poliomyelitus Hepatitus A Leptospirosis
Water-Washed Diseases Quantity of water more important
than quality of water Linked to personal and domestic hygiene
Water-Washed Diseases
Skin and Eye Infections
Skin sepsis Scabies Fungal Skin Infections Trachoma/Blindness
Others
Louse-borne Typhus
Water-Based Diseases
Vector based in water
Ingested Dracunculiasis or
Guinea Worm
Skin Penetrating Schistosomiasis
or Bilharziasis
Insect Vector Diseases
Spread by insects that :
– breed in water – bite near water.
Insect Vector Diseases
Breed in Water
malaria (anopheles) dengue (aedes) yellow fever (aedes) onchocerciasis or river blindness
(simulium black fly)
Bite Near Water
trypanosomiasis or sleeping sickness (glosina tsetse fly)
TRANSMISSION MECHANISMS
PREVENTIVE STRATEGIES
Water Borne (Cholera)
•Improve quality of drinking water•Prevent casual use of unimproved sources
Water Washed(Cholera, Scabies)
•Increase water quantity used•Improve accessibility and reliability of domestic water supply•Improve hygiene practices
Water Based(Guinea Worm)
•Decrease need for contact with infected water•Control snail population (water treatment)•Reduce contamination of surface waters by excreta
Water Related(Malaria)
•Improve surface water management•Destroy breeding sites of insects•Decrease need to visit breeding sites•Use (impregnated) mosquito netting•Do Indoor Residual Spraying
Reduce Reservoir
Interrupt Transmission
Prevent Disease in population
Treat Disease in person
Reservoir transmission Host
Control of Diseases Related to WHS