Concentration of foodborne viruses eluted from fresh and frozen produce: Applicability of ultrafiltration.

Foodborne illnesses involving raw and minimally processed foods are often caused by human noroviruses (HuNoV) and hepatitis A virus (HAV). Since food is contaminated usually with small numbers of virions, these must be eluted from the food surface and then concentrated for detection. The objective of this study was to optimize an ultrafiltration (UF) concentration method for HAV and HuNoVs present on various fresh and frozen produce. The detection range of the optimized method and its applicability to different food matrices was compared to the reference method ISO 15216-1:2017. Strawberry, raspberry, blackberry, lettuce, and green onion (25 g) were contaminated with HAV, HuNoV GI.7 and HuNoV GII.4 and then recovered therefrom by elution. A commercial benchtop UF device was used for the concentration step. Viral RNA was extracted and detected by RT-qPCR. From fresh strawberries, recovery of HAV loaded at 104 genome copies per sample was 30 ± 13 %, elution time had no significant impact, and UF membrane with an 80-100 kDa cut-off in combination with Tris-glycine elution buffer at pH 9.5 was found optimal. At lower copy numbers on fresh strawberry, at least 1 log lower numbers of HuNoV were detectable by the UF method (103 vs 104 GII.4 copies/sample and 101 vs 103 GI.7 copies/sample), while HAV was detected at 101 genome copies/sample by both methods. Except on raspberry, the UF method was usually equivalent to the ISO method regardless of the virus tested. The UF method makes rapid viral concentration possible, while supporting the filtration of large volume of sample. With fewer steps and shorter analysis time than the ISO method, this method could be suitable for routine analysis of viruses throughout the food production and surveillance chain.

The possibility of spreading herpes simplex virus type 1 via food handling and sharing.

AIMS: Herpes simplex virus type 1 (HSV-1) is an enveloped virus that causes recurrent and incurable diseases in 67% of the world population. Although it is not listed as a foodborne virus, some studies have shown that it can be recovered from surfaces as well as food. METHODS AND RESULTS: We investigated its persistence at -20°C, 4°C, 20°C, or 37°C for up to 7 days on stainless steel, aluminum, glass, polypropylene, cheddar cheese, sliced almond, and apple skin and in cola soft drink, orange juice, coffee, and milk, as well as its transferability from stainless steel to dry or moistened nitrile or latex gloves over time at typical ambient temperatures. Based on the plaque assay on Vero cells, HSV-1 persisted at least 24 h on all surfaces and at least 1 h on food matrices but was inactivated quickly in cola soft drink. Temperature and pH affected HSV-1 infectivity. Transfer of HSV-1 at a contact pressure of 1 kg cm2-1 for 10 s occurred only on latex, especially moistened. CONCLUSIONS: Our data on the persistence of HSV-1 on food-related surfaces suggest that some risk may be associated with sharing foods with infected carriers.

Neuromuscular Activation Differences During Gait in Patients With Ehlers-Danlos Syndrome and Healthy Adults.

OBJECTIVE: Ehlers-Danlos syndrome (EDS) is a group of genetic disorders affecting connective tissue. Symptoms include joint and ligament laxity. The objectives of this study were to compare muscle activation, joint angles, and spatiotemporal parameters during gait, and to compare isometric strength between participants with EDS (hypermobility and classical subtypes) and healthy adults. METHODS: Participants with EDS (n = 14) and healthy adults (n = 14) were recruited for this cross-sectional study. Lower extremity muscle activation, sagittal joint angles, and spatiotemporal parameters during gait were measured using surface electromyography (EMG), motion capture, and force plates. Isometric strength of the lower extremity joints was measured with an isokinetic dynamometer. Important characteristics (principal components [PCs]) were determined from EMG and angle waveforms using PC analysis; relationships between PC scores and groups were examined using multilevel linear models after accounting for gait speed. Spatiotemporal parameters and strength were compared using independent t-tests and effect sizes (Cohen's d coefficient). RESULTS: The EDS group was associated with delayed vastus lateralis (b = 16.69) and medialis activation (b = 11.33), higher rectus femoris (b = 28.34) and tensor fascia latae activation (b = -11.06), prolonged gluteus medius activation (b = -32.78), and lower medial gastrocnemius activation (b = -27.18). Joint angles were similar between the EDS and healthy groups. The EDS group had slower gait speeds, shorter stride lengths, and a greater percentage of time in stance (d = -1.05 to 0.96). The EDS group had weaker hip and ankle muscles (d = -0.83 to -0.97). CONCLUSION: Alterations in muscle activation and spatiotemporal parameters during gait in patients with EDS may be a result of impaired proprioception and balance and muscle weakness. Interventions should target these deficits.