Search

The objective of this study was to evaluate the efficacy of ultraviolet C light (UVC) for inactivating Senecavirus A (SVA) on three different experimentally contaminated surfaces commonly found in swine farms. An experimental study under controlled conditions assessed the effect of UVC on an SVA isolate on coupons composed of three surface types: cardboard, cloth, and plastic. Each coupon was inoculated with 2 mL of SVA (107.5 TCID50/mL) and 1 mL of PBS or 1 g of feces on the top or bottom surface of the coupon and allowed to dry (90 min at 25℃). Coupons were exposed to UVC in a commercially available pass-through chamber (PTC) for 5 min or in a simulated supply entry room (SER) for 120 min. After exposure, virus isolation was attempted from each coupon and virus titers were determined in cell culture. The efficacy of UVC was determined by the reduction in virus titer for the UVC treated groups compared to their respective non-treated positive controls. UVC was effective at inactivating SVA on plastic surface free of organic material. The plastic coupons inoculated with SVA and PBS had a significantly lower virus titer (>7-log reduction) in both the PTC and SER when compared to their relative positive controls. All other groups in the PTC and SER had a 2-log reduction or less. The reduction in virus titer on the top and bottom inoculated surfaces, following exposure to UVC, were not statistically different. The data from this study provide some guidance when applying UVC for disinfection in the field.

Knowledge about the total waste generated by the production of consumer goods can help raise awareness among policy-makers, producers and consumers of the benefits of closing loops in a future circular economy, avoiding unnecessary production and production steps and associated generation of large amounts of waste. In strict life cycle assessment practice, information on waste outputs from intermediate industrial processes of material and energy transformation is translated into and declared as potential environmental impacts, which are often not reported in the final results. In this study, a procedure to extract available intermediate data and perform a systematic pre-consumer waste footprint analysis was developed. The pre-consumer waste footprint concept was tested to analyse 10 generic products, which provided some novel and interesting results for the different product categories and identified a number of challenges that need to be resolved in development of the waste footprint concept. These challenges include standardised data declaration on waste in life cycle assessment, with a separation into waste categories illustrating the implicit environmental and scale of significance of waste types and quantities (e.g. hazardous waste, inert waste, waste for recycling/incineration) and establishment of a common definition of waste throughout sectors and nations.

It is well established that the contamination sources of cholera causing bacteria, Vibrio cholerae, are water and food, but little is known about the transmission role of the fomites (surfaces that can carry pathogens) commonly used in households. In the absence of appropriate nutrients or growth conditions on fomites, bacteria have been known to assume a viable but non-culturable (VBNC) state after a given period of time. To investigate whether and when V. cholerae O1 assumes such a state, this study investigated the survival and viable quantification on a range of fomites such as paper, wood, glass, plastic, cloth and several types of metals under laboratory conditions. The fomites were inoculated with an outbreak strain of V. cholerae and its culturability was examined by drop plate count method at 30 min intervals for up to 6 h. For molecular detection, the viable/dead stain ethidium monoazide (EMA) which inhibits amplification of DNA from dead cells was used in combination with real-time polymerase chain reaction (EMA-qPCR) for direct quantitative analyses of viable V. cholerae at 2, 4, 6, 24 h and 7 day time intervals. Results showed that V. cholerae on glass and aluminum surfaces lost culturability within one hour after inoculation but remained culturable on cloth and wood for up to four hours. VBNC V. cholerae on dry fomite surfaces was detected and quantified by EMA-qPCR even 7 days after inoculation. In conclusion, the prolonged survival of V. cholerae on various household fomites may play vital role in cholera transmission and needs to be further investigated.

Point-of-care (POC) diagnostics play an important role in delivering healthcare, particularly for clinical management and disease surveillance in both developed and developing countries. Currently, the majority of POC diagnostics utilize paper substrates owing to their affordability, disposability, and mass production capability. Recently, flexible polymer substrates have been investigated due to their enhanced physicochemical properties, potential to be integrated into wearable devices with wireless communications for personalized health monitoring, and ability to be customized for POC diagnostics. Here, we focus on the latest advances in developing flexible substrate-based diagnostic devices, including paper and polymers, and their clinical applications at the POC.