ABSTRACT
This study investigated the recovery and absorption rates of murine norovirus, a surrogate for human norovirus, by using NanoCeram(R) filters which served as a tool for recovering viruses. In the study, two types of NanoCeram(R) filters were employed: one was a cartridge type and the other was a disc type (phi 47 mm) whose surface area is 75 times smaller than the cartridge type. The analytical method was the real-time reverse transcription-polymerase chain reaction (RT-PCR). The study found that the average recovery rates of the cartridge type and the disc type were 30.9% and 29.5% respectively. Since these two rates were very close to each other, the adsorption rate of the cartridge type could be predicted with the disc type. Analyzing recovery and absorption rates of the disc type based on different filtered volumes showed that when the volume increased from 0.5 L to 20 L, the average recovery rate rose from 14.78% to 30.41 %, while the average absorption rate dropped from 56.33% to 10.48%. The increase in turbidity from less than 1 NTU to less than 3 NTU raised the average recovery rate from 47.23% to 82.84%.
Subject(s)
Humans , Absorption , Adsorption , NorovirusABSTRACT
The information of species and quantity of enteric viruses in surface water, finished water, and tap water is important in helping understand the pathogenesis of viruses, providing information about health and hygiene, improving handling technique of drinking water, and establishing the standards of water quality. Using standard total culturable virus assay-most probable number (TCVA-MPN) method, we tried to detect infectious enteric viruses in surface water, finished water, and tap water samples that were collected and evaluated according to the information collection rule (ICR). The results obtained with TCVA method were compared to the results from both reverse transcription-polymerase chain reaction (RT-PCR) and integrated cell culture-RT-PCR (ICC-RT-PCR) method. Five of 86 samples (5.8%) were positive as determined by the TCVA-MPN method. Two of 86 samples (2.3%) were positive for reovirus as determined by the RT-PCR and ICC-RT-PCR, and contained infectious reovirus. One of 86 samples (1.7%) was positive for coxsackievirus type B3 as determined by the RT-PCR and ICC-RT-PCR.
Subject(s)
Drinking Water , Hygiene , Water Quality , WaterABSTRACT
The effective inactivation of microorganisms in drinking water by Ultraviolet (UV) irradiation is regarded as a new low-cost water treatment method shoeing high removal rate of relatively stable infectious virus particles including poliovirus. In the present study, we examined virus inactivation by UV in various water environments. Samples were collected from finished water and surface water, and tested for turbidity. UV dose of 18, 22, 30, 36 and 40 milli-Joule (mJ)/cm2 were used by combination of 2 mW/cm2 UV intensity and time of 9, 11, 15, 18 and 20 second. Depths of water were fixed at 0.37 cm and 8 cm, and virus titers were shown by plaque forming unit (PFU). Poliovirus was inactivated to 99.0% by 18 mJ/cm2 of UV dose in the condition of 0.08 Nephelometry Turbidity Unit (NTU) and 8 cm depth of water. Poliovirus at 30 mJ/cm2 of UV dose under the same condition was inactivated to 99.7%. Furthermore, Poliovirus at 56.60 NTU and 8 cm depth of water was inactivated to 92.0% and 98.5% by 18 mJ/cm2 and 30 mJ/cm2 of UV dose, respectively. The degrees of virus inactivation were dependent upon the UV dose, the turbidit, y and the depth of water. In conclusion, introduction of UV disinfections can be considered in drinking water purification systems in case reasonable engineering support is possible.
Subject(s)
Drinking Water , Nephelometry and Turbidimetry , Poliovirus , Shoes , Virion , Virus Inactivation , Water Purification , WaterABSTRACT
The effective inactivation of microorganisms in drinking water by Ultraviolet (UV) irradiation is regarded as a new low-cost water treatment method shoeing high removal rate of relatively stable infectious virus particles including poliovirus. In the present study, we examined virus inactivation by UV in various water environments. Samples were collected from finished water and surface water, and tested for turbidity. UV dose of 18, 22, 30, 36 and 40 milli-Joule (mJ)/cm2 were used by combination of 2 mW/cm2 UV intensity and time of 9, 11, 15, 18 and 20 second. Depths of water were fixed at 0.37 cm and 8 cm, and virus titers were shown by plaque forming unit (PFU). Poliovirus was inactivated to 99.0% by 18 mJ/cm2 of UV dose in the condition of 0.08 Nephelometry Turbidity Unit (NTU) and 8 cm depth of water. Poliovirus at 30 mJ/cm2 of UV dose under the same condition was inactivated to 99.7%. Furthermore, Poliovirus at 56.60 NTU and 8 cm depth of water was inactivated to 92.0% and 98.5% by 18 mJ/cm2 and 30 mJ/cm2 of UV dose, respectively. The degrees of virus inactivation were dependent upon the UV dose, the turbidit, y and the depth of water. In conclusion, introduction of UV disinfections can be considered in drinking water purification systems in case reasonable engineering support is possible.