water microbiology NE2283 (1).ppt

Water

• Presently 1.1 billion people lack access to improved water supply

• 2.4 billion to improved sanitation.• Unless action is taken, the number

of people who lack access to improve water supply could increase to 2.3 billion by 2025.

• One in every six human beings has no access to clean water within a km of their homes.

• Half of all people in developing countries has no access to proper sanitation.

• Off all water on earth, 97.5% is salt water.

• Only 2.5 % is fresh water.

• Some 70% is frozen in the polar icecaps.• 30% is mostly present as soil moisture or

lies in underground.

• Less than 1% of the world’s fresh water

• (0.007% of all water on earth)

• Is readily accessible for direct human use.

Raw water sources

• Surface water• River • Lake• Well

• Freshwater shortages are likely to trigger increased environmental damage over the next 15 years.

By 2020,• Fall in river flows• Rising saltiness of estuaries.• Loss of fish and aquatic plants species• Reduction in sediments to the coast

are expected to rise in many areas of the globe.

Water loss will result in

• Intensify farmland losses• Food insecurity• Damage to fisheries• Rises in malnutrition and diseases.

• A person can live about a month without food but only about a week without water

• The average American uses 450 liters to 782 liters of water each day while the average African family uses 22 liters.

• More than 200 million hours are spent each day by women and girls to collect water from distant often polluted source.

60 to 70% of the rural populations in the developing world have

• neither access to a safe and convenient source of water

• Neither a satisfactory means of water disposal.

• United Nations reported(2007)• 20% of the world population in 30

countries face water shortages. (2025)• 30% of the world population in 50

countries face water shortages

• Each year• More than 5 million people die from

water-related disease

• Of the 37 major diseases in developing countries, 21 are water and sanitation related.

• The leading cause of child death in the world is diarrhoea.

Water microbiology

• 1. health

• 2. environment

Water & Diseases

• Water borne disease

- etiological agent trasmitted via ingestion (cholera, Hepatitis A)through contact with water (schistosomiasis, guinea worm

disease)

Water associated diseases

• Disease where the incidence is associated with the ability to obtain enough water resources.

- incidence of trachoma in Middle East,North Africa and Sahara.- Reduce with the increase of hygienic

status with enough water resources

• Water-borne diseases (include water based diseases caused by parasites)

• water-associated diseases (also discussed as water-washed diseases)

• Water-related diseases such as dengue, malaria

• Diseases related to pollutants such as pesticides, heavy metals, PCH

Relationship between water- borne diseases with faecal contamination.

• If the diseases are spread through drinking water, then the presence of pathogens in water was due to the presence of faecal contaminants from the human or animal sources.

Epidemiological study of water-borne diseases• 1855

• Snow showed that the cholera outbreak in London was connected to the use of a well water in Broad Street which was found to be contaminated by sewage disposal.

2. 1856

- Budd correlate the outbreak of typhoid with contaminated drinking water with waste water.

Problems caused by water-borne diseases- More than 10% death in tropical and

developing countries are due to water-borne diseases.

- 5 - 8 million death/year caused by diarrhea on children.

Death due to rotavirus accounted to about 1 million/year

Comparison of cholera cases• U.S.A. ( 5 )• Bangladesh (14,171 )• India (30,894)• Indonesia (57,095)• Malaysia (730)

• Data in 1976 - 77

26 Ogos 2005

• cholera in West Africa

• “The current wave of cholera outbreaks started several weeks ago in West Africa. So far, 31 259 cases and 517 deaths have been reported in eight countries”

• Burkina Faso: 295 ( 8) • Guinea: 571 (32) • Guinea-Bissau: 9047 ( 172)• Liberia: 703 (29) • Mali: 158 (20) • Mauritania: 497 (10)• Niger: 125 (15) • .Senegal: 19 863 ( 231 )

Water-borne diseases with their etiological agents

• bacteria

• virus

• parasites

bacteria

• Shigellosis Dysentery• cholera• gastroenteritis• leptospirosis• meliodosis• salmonellosis• Typhoid fever• tularemia & yersinosis

virus

• Gastroenteritis- Norwalk virus, rotavirus, coronavirus

Hepatitis virus- virus hepatitis A

Enterovirus

parasites

• Dysenteric amoeba- Entamoeba hystolytica

• meningoencephalitis- Naegleria, Acanthamoeba

Giardiasis- Giardia lamblia

• Schistosomiasis

- S. mansoni, S. japonica, S. haematobium

Indicator of Faecal contamination• It is not practical to screen for the

presence of all pathogens in water samples.

• WHY ???

1.

• There are too many pathogens in the water samples and each pathogen required a specific test which are different from others for their detections.

2

• The concentration of pathogens found in the water samples are too low in numbers and as such difficult to detect.

3

• The presence of pathogens in contaminated water is detected at random (depending on the place where it is found)

4

• If a pathogen is identified, it maybe too late for the public to be informed of such an incidence.

Indicator for Water contamination • Due to the presence of many

pathogens and many specific tests for each pathogens, therefore drinking water is monitor using indicator organisms.

Indicators

• Physical/chemical indicators

• eg. Concentration of coprostanol in faeces

• coprastanol - type of faecal sterol found only in higher animals and human.

MICROBIOLOGICAL INDICATOR• BACTERIA• VIRUS• ENZYME• BACTERIA TOXIN• MICROBIAL ANTIGEN• GENETIC MARKERS

bacteria flora in the gut

• AnaerobesBacteriodesBifidobacterium

• Lactobacillus• E. coli• Streptococcus/Enterococcus

faecalis

• coliform• Faecal coliforms (FC)

• Was used traditional in water quality

• Drinking water == === 0/100 ml water

Definition

• Facultative anaerobes• Gram negative rod• Non spore formers• Lactose fermenter with production

of gas in 48 hours.• Temp. 35 o C.

Faecal coliform

• coliform from the gut of animals/human

• Cultured at temp. of 44.5 o C.

Faecal Streptococcus/enterococcus• Streptococcus/faecal enterococcus• (FS)

• FC/FS > 4.0 contamination due to human

• FC/FS < 0.7 contamination due to animals

Other bacteria

• Clostridium perfringens• Bifidobacteria sp.• Bacteroides sp.• Acid resistant bacteria• Heterotrophic bacteria

Fungus

• Chlorine resistant yeasts.

Virus

• coliphage

• Enterovirus

Monitoring of bacterial contamination in Malaysia• Total coliforms• MOH: 5,000/100 ml waterSg. Selangor/MADA Canal raw water treated

water• Total coliform 1600000 < 1.1• 2400 < 1.1

(MPN)

CRITERIA For Faecal indicator• 1. Indicator must be present when

the pathogen is present and absent in clean water.

• 2. Indicator must be present in higher concentration/numbers than pathogens.

• 3. Indicator must not proliferate more than the pathogen in normal environment.

• 4. Indicator must have the same resistance towards inactivation whether in normal conditions, in treated water or in disinfection processes.

• 5. Indicator must be easily isolated and identified.

Index Organisms

• Was used to detect the effectiveness of the water processing system.

• Can be present in the water naturally or add intentionally.

criteria for Index organism

• 1. Index organisms must have similar physical and physiological characteristic of the pathogens that it represent.

• 2. Index organisms must be more resistance to inactivation process as compared to pathogens.

• 3. Index organisms must not be pathogen and can be easy to monitor.

Water environment

• Microbial ecology• Monitoring of environmental

pollutions.• Bio-remediation• Genetic engineering in micro

organisms survival.

Survival of microbes in the environment• autochthnous organisms

• Organisms found, survive and proliferate naturally in the environments.

• Allochthnous organisms

• Organisms that do not survive or proliferate naturally in an environment. The presence of the organisms in the particular ecosystem is temporary/transient.

Factors that affect the survival of microbes in water.• Abiotic Factor

• pH• Oxygen concentration• light• temperature• Sediment and suspended solids. • Presence of nutrients.

• Ions concentrations.• Chemical concentrations.• salinity• Osmotic stress

Sg. Air Hitam

• pH• Turbidity• Colour• Free chlorine• Total chlorine• Fluoride• Al, Fe, Mn, ammonia

Biotic factor

• Predation• commensalisms • competitions