Development of an elution device for ViroCap virus filters

Abstract

Environmental surveillance of waterborne pathogens is vital for monitoring the spread of diseases, and electropositive filters are frequently used for sampling wastewater and wastewater-impacted surface water. Viruses adsorbed to electropositive filters require elution prior to detection or quantification. Elution is typically facilitated by a peristaltic pump, although this requires a significant startup cost and does not include biosafety or cross-contamination considerations. These factors may pose a barrier for low-resource laboratories that aim to conduct environmental surveillance of viruses. The objective of this study was to develop a biologically enclosed, manually powered, low-cost device for effectively eluting from electropositive ViroCap™ virus filters. The elution device described here utilizes a non-electric bilge pump, instead of an electric peristaltic pump or a positive pressure vessel. The elution device also fully encloses liquids and aerosols that could contain biological organisms, thereby increasing biosafety. Moreover, all elution device components that are used in the biosafety cabinet are autoclavable, reducing cross-contamination potential. This device reduces costs of materials while maintaining convenience in terms of size and weight. With this new device, there is little sample volume loss due to device inefficiency, similar virus yields were demonstrated during seeded studies with poliovirus type 1, and the time to elute filters is similar to that required with the peristaltic pump. The efforts described here resulted in a novel, low-cost, manually powered elution device that can facilitate environmental surveillance of pathogens through effective virus recovery from ViroCap filters while maintaining the potential for adaptability to other cartridge filters.Electronic supplementary materialThe online version of this article (10.1007/s10661-017-6258-y) contains supplementary material, which is available to authorized users.

Evaluation of Sampling and Concentration Methods for Salmonella enterica Serovar Typhi Detection from Wastewater

“…The main differences between the two methods were the input for DNA extraction (half of the resuspended pellet versus the full sample pellet) and the resulting difference in effective volume assayed (Table 1, Supplemental Information). 20,21,41 Differential centrifugation. Three versions of differential centrifugation methods were used: DC-D-50 mL, DC-SF-50 mL, and DC-D-1 L. All methods involved centrifugation for 1 minute at 1,000 3g, 4 C), followed by transfer of the supernatant centrifuging again (15 minutes, 4,000 3g, 4 C).…”

Evaluation of sampling and concentration methods for Salmonella enterica serovar Typhi detection from wastewater

“…Two variations of the two-inch filter cartridge method were tested, mentioned hereafter as FC1-D and FC2-D. The main difference between the two methods was the input for DNA extraction (half of the resuspended pellet vs. the full sample pellet) and the resulting difference in effective volume assayed (Table 1, Supplementary Information) [20,21,41].…”

Validation of the bag‐mediated filtration system for environmental surveillance of poliovirus in Nairobi, Kenya

“…All filters were processed by a single 30‐min elution using 100 ml pH 9·5 eluent containing 1·5% beef extract (Becton Dickinson) and 0·05 mol l −1 glycine (Fisher Scientific, Hampton, VA (KEMRI); Merck KGaA, Darmstadt, Germany (UP)) (Fagnant et al . 2017b, 2018; Zhou et al . 2018).…”

“…For filters shipped to UP, a 2% sodium benzoate (Becton Dickinson, Sparks, MD) and 0Á2% calcium propionate (Becton Dickinson) preservative mixture was passed through the filter at KEMRI (Fagnant et al 2017a). All filters were processed by a single 30-min elution using 100 ml pH 9Á5 eluent containing 1Á5% beef extract (Becton Dickinson) and 0Á05 mol l À1 glycine (Fisher Scientific, Hampton, VA (KEMRI); Merck KGaA, Darmstadt, Germany (UP)) (Fagnant et al 2017b(Fagnant et al , 2018Zhou et al 2018). Secondary concentration was performed on the eluate by polyethylene glycol (PEG) precipitation (Meleg et al 2008;Kiulia et al 2010), with addition of 14 g PEG 8000 (Sigma Aldrich (KEMRI); Amresco LLC, Solon, OH (UP)) 1Á17 g sodium chloride (NaCl) (Sigma Aldrich), overnight incubation (room temperature (KEMRI) or 4°C (UP)), and centrifugation (2500 g (KEMRI) or 6500 g (UP), 30 min).…”