Download Waterborne Infections

Waterborne Infections
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Create an environment to maintain
ecological conditions to promote
health and prevent disease
Public Health issue: Safe drinking
water and proper sanitation
Water
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International Drinking Water Supply and
Sanitation decade: 1981-1990
34 World Health Assembly emphasized
that safe drinking water is a basic element
of primary health care – key to attainment
of Health for all
Safe Drinking Water
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Free from pathogenic agents
Free from harmful chemicals
Pleasant to taste
Usable for domestic purposes
Water requirement
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2 litres per head per day: Basic
physiological requirement
PH: Adequate water supply to
maintain proper hygiene
15-200 l/per capita adequate
India 40 l/ capita target
Sources of Water Supply
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Rain
Surface:
 Impounding reservoirs
 Rivers and Streams
 Tanks/ Ponds/ Lakes
Ground water
 Shallow wells
 Deep wells
 Springs
Water Pollution
Gases: Nitrogen, Carbon dioxide,
Hydrogen Sulphide
 Minerals: Salts of Ca, Mg
 Suspended impurities: Clay, Silt,
Sand, Mud
 Microorganisms
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Water Pollution due to Urbanization
Sewage: Decomposable organic
matter and microbes
 Industrial and trade wastes
 Agricultural pollutants
 Physical
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Health Hazards
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60% towns getting adequate water
Low daily per capita supply
Inefficient distribution
Leakage
Progress in rural sector very slow
Few Sewage treatment plants
Poor hygiene: Poorly designed/ maintained
sewage system
Fertilizer: Human discard
Diarrhea and intestinal worm
infestation: 10% total burden of
disease in the developing world.
 Inadequate water supply
increases risk of Schistosomiasis,
guinea worm disease, skin and
eye infections.
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Population with Access to Safe
Water (%)
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India
Bangladesh
Indonesia
Nepal
Maldives
SriLanka
Thailand
85
80
63
48
88
57
70
Population with Access to
Adequate Sanitation
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India
Bangladesh
Indonesia
Nepal
Maldives
SriLanka
Thailand
29
30
51
22
40
66
74
AETIOLOGICAL AGENTS
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Bacteria
Vibrio cholerae
 Salmonella
 Campylobacter
 Shigella
 diarrheogenic Escherichia coli.
 Legionella pneumophila
 M. xenopi, M. abscessus, M. fortuitum,
and M. chelonae
 Leptospira
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Viruses
 Hepatitis A and E
 Polio virus
 Rotavirus, Adenovirus, Norwalk agent
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Helminthic
 Roundworm
 Whipworm
 Hydatid Disease
Protozoal
Giardia lamblia
 Entamoeba histolytica
 Acanthamoeba,
 Hartmannella
 Naegleria fowleri
 Cyclospora
 Isospora
 Cryptosporidium
 Microsporidia
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Bacterial infections
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Presenting symptoms:
 Diarrhea:
Cholera
 Dysentery: Shigellosis
 Flu like illness (Pontiac fever)
 Pneumonia (Legionnaire’s disease)
 Bacteremia (Typhoid)
 Septicemia (Leptospira)
Cholera
7 Pandemics: Last in 1961
 Vibrio cholerae O1, non O1, O139
 Transmission via water
contaminated with faeces
 Rice Water Stools
 Dehydration, electrolyte
imbalance
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Typhoid
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Systemic infection
Salmonella Typhi
Can be sporadic, epidemic, endemic
Endemic in India
Man is the only reservoir
Peaks in July-September
Transmisison Feco-oral. Directly or
indirectly by ingestion of
contaminated wtare/ milk/food
Continuous fever- 3-4 weeks
Involvement of Lymphoid tissue
Viral Infections
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Gastroenteritis
Polio
Hepatitis
Parasitic Infections
Gastrointestinal disturbances
Encephalitis
Poliomyelitis
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Acute viral infection
Infection of alimentary canal.
CNS affected in 1%; paralysis, death
Feco-oral transmisison. Survives long
in cold environment.
Occurs mostly in rainy season
Environmental sources:
Contaminated Water, milk, food
Droplet in fection in acute phase of
disease
Viral Hepatitis
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Hepatitis A
Picornavirus
Fever, chills, generalized malaise,
vomiting, jaundice
Mode of transmisison: feco-oral
Hepatitis E: First major epidemic in
Delhi in 1955
Amoebiasis
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Entamoeba histolytica
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Infective form: cyst
Diarrhea – dysentry
Feco-oral transmission
Giardiasis
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Giardia lamblia
Abdominal discomfort- diarrhea
Feco-oral transmission
Infective form-Cyst
Diagnosis
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Signs and symptoms
Laboratory diagnosis
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Sample collection
Transport
Microscopy
Culture
Serological assays
Molecular diagnosis