In the field of chemical engineering and water treatment, the study of viruses, included surrogates, is well documented. Often, surrogates are used to study viruses and their behavior because they can be produced in larger quantities in safer conditions and are easier to handle. In fact, surrogates allow studying microorganisms which are non-infectious to humans but share some properties similar to pathogenic viruses: structure, composition, morphology, and size. Human noroviruses, recognized as the leading cause of epidemics and sporadic cases of gastroenteritis across all age groups, may be mimicked by the Tulane virus. The objectives of this work were to study (i) the ultrafiltration of Tulane virus and norovirus to validate that Tulane virus can be used as a surrogate for norovirus in water treatment process and (ii) the retention of norovirus and the surrogate as a function of water quality to better understand the use of the latter pathogenic viruses. Ultrafiltration tests showed significant logarithmic reduction values (LRV) in viral RNA: around 2.5 for global LRV (i.e., based on the initial and permeate average concentrations) and between 2 and 6 for average LRV (i.e., retention rate considering the increase of viral concentration in the retentate), both for norovirus and the surrogate Tulane virus. Higher reduction rates (from 2 to 6 log genome copies) are obtained for higher initial concentrations (from 101 to 107 genome copies per mL) due to virus aggregation in membrane lumen. Tulane virus appears to be a good surrogate for norovirus retention by membrane processes.

West Nile Virus (WNV) is a member of the Japanese Encephalitis (JE) serocomplex within the Flaviviridae family. We report four whole blood donors and one plasma donor with WNV nucleic acid test (NAT)-reactive donations between September 2018 and November 2019, following recent Japanese Encephalitis virus (JEV) vaccination.
Cases 1 and 4 had reactive WNV NAT donations 1 day after receiving the JEV vaccine. Case 2 had a reactive WNV donation 3 days after receiving the JEV vaccine. Case 3 had a reactive WNV NAT donation 3 days after returning from Arizona and 1 day after receiving the JEV vaccine. Case 5 had a reactive WNV donation the same day as receiving the JEV vaccine.
WNV screening used the Roche cobas WNV nucleic acid test (NAT) (Roche Molecular Systems). Reference testing on WNV-reactive donations was carried out by the National Microbiology Laboratory (NML). JEV vaccine dilutions were also analyzed.
Supplemental NAT was negative for WNV and JEV for Cases 1, 3, and 5. Case 2 had a weak amplification curve for one of two JEV NAT targets. Case 4 was JEV NAT-positive, WNV NAT-negative. Serologic testing on donation specimens for Cases 2, 4, and 5 did not support recent or remote WNV infection. JEV vaccine dilutions were detected by both cobas and supplemental NAT.
We recommend implementing a temporary blood donor deferral following a JEV vaccination, if screening utilizes a WNV assay with the capability of detecting other members of the JE serocomplex.

The challenges associated with operating electron microscopes (EM) in biosafety level 3 and 4 containment facilities have slowed progress of cryo-EM studies of high consequence viruses. We address this gap in a case study of Venezuelan Equine Encephalitis Virus (VEEV) strain TC-83. Chemical inactivation of viruses may physically distort structure, and hence to verify retention of native structure, we selected VEEV strain TC-83 to develop this methodology as this virus has a 4.8 Å resolution cryo-EM structure. In our method, amplified VEEV TC-83 was concentrated directly from supernatant through a 30 % sucrose cushion, resuspended, and chemically inactivated with 1 % glutaraldehyde. A second 30 % sucrose cushion removed any excess glutaraldehyde that might interfere with single particle analyses. A cryo-EM map of fixed, inactivated VEEV was determined to a resolution of 7.9 Å. The map retained structural features of the native virus such as the icosahedral symmetry, and the organization of the capsid core and the trimeric spikes. Our results suggest that our strategy can easily be adapted for inactivation of other enveloped, RNA viruses requiring BSL-3 or BSL-4 for cryo-EM. However, the validation of inactivation requires the oversight of Biosafety Committee for each Institution.

This work is a proof of concept of how a sequence of industrial batch separation steps together are used to form an integrated autonomous downstream process. The sequence in this case study consisted of an anion chromatography step, virus inactivation and finally a hydrophobic chromatography step. Moving from batch to integrated separation minimizes hold-up times, storage tanks, and required equipment. The conversion from batch to integrated mode is achieved by extracting operating points and separation data from batch chromatograms. The integrated separation process is realized on an ÄKTA Pure controlled by an open research software called Orbit, making it possible to operate complex process configurations including multiple steps. The results from this case study is the principle and method of the steps taken to automation, achieving a more continuous and efficient downstream process.

Arbovirus infections are increasing in prevalence worldwide. This presents new risks for blood transfusion. This article describes the epidemiology and surveillance of West Nile Virus, dengue and chikungunya and their role in the risk management of transfusions. Arboviruses are RNA viruses and very adaptable by nature. The majority of arbovirus infections are zoonoses. The risk of transmission is multifactorial and concerns the virus, vectors, animal reservoirs, the environment and human behaviour. In recent years, West Nile Virus has become established and widespread in North America, the number of cases of dengue worldwide has increased dramatically, and major epidemics of chikungunya have occurred in the Indian Ocean and Asia. The transmission of dengue and chikungunya is demonstrated in temperate zones. All arboviruses are potentially transmissible by transfusion due to their capacity to induce an asymptomatic viremic phase. The risk of West Nile Virus transmission via transfusion is recognised and prevention measures are well established. The risk of transmission via transfusion of dengue and chikungunya is real but difficult to quantify and the optimum prevention strategy is currently the subject of research. Access to up-to-date epidemiological data is an essential aid to decision-making, especially for donors returning from endemic areas to Europe. The challenge is to define and implement appropriate measures in unpredictable situations.

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A probabilistic model was used to compare cryoprecipitate to viral inactivated, commercial fibrinogen concentrate to evaluate with regard to the recipient\'s risk of exposure to an emergent AIDS-like epidemic. In patients who occasionally need a therapeutic dose of fibrinogen, commercial fibrinogen would be marginally safer than cryoprecipitate if the new pathogen were sensitive to inactivation. But there is a potential high risk of exposure if the emerging agent withstands inactivation. In most of the analyzed scenarios, cryoprecipitate is safer than commercial fibrinogen as long as the odds that the new agent is sensitive to inactivation are lower than 1.000 to 1.