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Bacteriophages as one of possible indicators, of water bacterial
pollution and water bacterial clean up assistants
Current water
protection initiative is a unique occasion to remind everybody of the
vital difference that clean water makes to our health, and how it born
diseases through source water protection can reduce disease.
Nowadays objectives as to water supplies
include protecting facilities and systems, responding to and
recovering from a terrorist attack, and continuing government
operations in a national emergency.
Waterborne diseases are
the most important concern about the quality of water. Developing
countries and rural
communities are particularly vulnerable. In developed countries the
mortality due to
waterborne diseases is low, but the socio-economic impact is
phenomenal
(Avendano et al,
1993; Payment, 1993).
Phages can
replicate only in specific host bacteria, which implies that the
phages of E. coli
(coliphages) are, like
their hosts, related to faecal pollution. Phages commonly used in
water
quality assessment
include the groups of phages known as somatic and male-specific
coliphages, which each
have their own indicator advantages and disadvantages. Phages which
infect Bacteroides
fragilis strain HSP40 are highly specific for human faeces, and
can be used to
distinguish between
faecal pollution of human and animal origin (Grabow et al,
1994b).
Evidence supporting the
indicator value of phges is accumulating, and their inclusion in
quality
monitoring protocols is
gaining ground rapidly.
Various groups and
types of bacteriophages, particularly those of coliform bacteria (Coliphages)
and those of bacterioidesspp., have been proposed as indices of faecal
pollution and as indicators of treatment efficiency for both water and
wastewater-treatment process. Leclere (2000) has reviewed the
literature on the use of bacteriophages and concludes that they have
significant limitations as indices of faecal pollution and enteric
viruses. However other published evidence indicator that
bacteriophages have potential value as indices of faecal contamination
and indicator of treatment effectiveness indicators of treatment
effectiveness. (Sobsey at al., 1995 Grabov, 2001)
Coliphages are
detectable by simple, inexpensive and rapid methods that can be
applied in a basic routine bacteriology laboratory.
Some internationally
standardized methods exist (e.g. ISO 10705-1; 10705-2; 10705-4) They
are generally not
Considered to be a
health risk for laboratory workers although some of the host bacterial
strains may be opportunistic pathogens.
EPA methods related to
bacteria, viruses:
Method 1604: Total
Coliforms and Escherichia coli
in Water by Membrane Filtration Using a Simultaneous Detection
Technique (MI Medium) (September 2002)
Method 1601:
Male-specific (F+) and Somatic Coliphage in Water by Two-step
Enrichment Procedure (April 2001)
Method 1602:
Male-specific (F+) and Somatic Coliphage in Water by Single Agar Layer
(SAL) Procedure (April 2001)
Method 1103.1: Escherichia coli (E.
coli) in Water by Membrane Filtration Using membrane-Thermotolerant
Escherichia coli Agar (mTEC) (September 2002) |
