Short- and long-term variations of norovirus concentrations in the Meuse river during a 2-year study period.
Faecally impacted surface waters used for drinking water production may encompass risk for norovirus infections. To be able to assess a possible health risk, noroviruses should be quantified and fluctuations identified. In 2001, norovirus concentrations in the river Meuse displayed a seasonal distribution with high peaks during wintertime as determined by RT-PCR on serially diluted RNA. An intensified day-by-day sampling scheme in the winter of 2002/2003 revealed that the winter peak consisted of several peaks of varying duration and magnitude, possibly due to contamination events in the catchment. The highest estimated concentration was 1700 PCR-detectable units per litre (95% CI 250-8000), which if coinciding with failing treatment could lead to significant numbers in drinking water. Adaptive dynamic filtering was shown to adequately predict subsequent sample concentrations. If valid, such analyses could prove to be useful as early warning systems in risk management of water sources.
Westrell
Therese
T
Department of Parasitology, Mycology and Water Microbiology, Swedish Institute for Infectious Disease Control (SMI), 17182 Solna, Sweden.
Teunis
Peter
P
van den Berg
Harold
H
Lodder
Willemijn
W
Ketelaars
Henk
H
Stenström
Thor Axel
TA
de Roda Husman
Ana Maria
AM
D009426:Netherlands; D029322:Norovirus / Q000302:isolation & purification*; D011336:Probability; D045483:Rivers / Q000382:microbiology*; D013997:Time Factors