Conclusion
Enterovirus, rotavirus, astrovirus, total coliform, faecal
coliform, enterococci and coliphages considered in this
study were present in water to be used for irrigation.
The abundant presence of indicator bacteria and enteric
viruses in irrigation water proves a continuous raw residual
water supply to the aquatic system.
Viral presence in irrigation water, for the specific tropical
highland system under study, is similar to that previously
reported for temperate zones, during the colder months.
The detection of indicator bacteria in the sources of drinking
water shows the contribution of faecal matter in the
aquifer and reinforces the need for an adequate disinfection
process in order to ensure good water quality in the
public supply system.
Analysis to identify the presence of coliphages as indicators
of faecal contamination is recommended. These
should be considered as complementary to bacterial indicators,
and to reflect the general survival conditions of
enteric viruses. The fact that coliphages are tolerant to
wastewater treatment makes them suitable indicators for
the evaluation of recycled water to be used for irrigation
and recreational purposes.
This low-cost strategy of using viral and bacterial indicators
to confirm water quality for drinking and irrigation is
attractive and advisable for low income countries,
reflected in a public health benefit.