INIQUI   05448
INSTITUTO DE INVESTIGACIONES PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Enteric viruses in recreational waters in the Province of Salta, Argentina: Quantitative Microbial Risk Assessment
Autor/es:
HUGO RAMIRO POMA; DOLORES GUTIÉRREZ CACCIABUE; VERÓNICA RAJAL
Lugar:
Florianópolis
Reunión:
Simposio; 17th International Symposium on Health related Water-Watermicro 2013; 2013
Institución organizadora:
IWA
Resumen:
Incidences
of diarrheal and parasitic disease in the human population were analyzed in the
main city of the Province of Salta using Geographic Information Systems, and the
results suggested a potential influence of Arenales River. To establish the
critical points for systematic monitoring, the river section that crosses the
city was assessed and eleven locations (five on the river and six on
discharges) were selected along the river. Physicochemical (temperature, pH,
dissolved oxygen, conductivity, salinity, and turbidity, using a multiparametric
probe) and microbiological variables including bacteria (total and thermotolerant
coliforms, E. coli, and Enterococcus, by colony forming units count),
parasites (by microscopy), and viruses (adenovirus [AdV], enterovirus [EV], and
norovirus [NoV] by real-time PCR) were analyzed monthly for thirteen months. As
the amount of viruses and parasites in environmental samples is usually low we used
ultrafiltration to concentrate pathogens from 20 L of water to 50-70 mL. All
samples were spiked with a known amount of the bacteriophage PP7 as internal
control of the process to evaluate the filtration recovery, to calculate the
sample limit of detection, and to assess enzymatic inhibition during PCR.
Multivariate
statistical techniques were used to evaluate correlations between physicochemical
variables, microbial indicators and the pathogens detected, and to design a
rational monitoring scheme for the optimum use of limited resources.
Finally, quantitative
microbial risk assessment (QMRA) was conducted using the densities of enteric
viruses obtained from the river to calculate the risk of contracting an
infectious disease caused by these microorganisms in water. Three scenarios
were considered: 1) ingestion by bathing adults (BA), 2) ingestion by bathing
children (BC), and 3) inhalation due to secondary contact (SC).