Knowledge of influenza A virus survival in different environmental conditions is a key element for the implementation of hygiene and personal protection measures by health authorities. As it is dependent on virus isolates even within the same subtype, we studied the survival of the 2009 H1N1 pandemic (H1N1pdm) virus in water and on non-porous surface. The H1N1pdm virus was subjected to various environmental parameters over time and tested for infectivity. In water, at low and medium salinity levels and 4°C, virus survived at least 200 days. Increasing temperature and salinity had a strong negative effect on the survival of the virus which remained infectious no more than 1 day at 35°C and 270 parts per thousand (ppt) of salt. Based on modeled data, the H1N1pdm virus retained its infectivity on smooth non-porous surface for at least 7 days at 35°C and up to 66 days at 4°C. The H1N1pdm virus has thus the ability to persist in water and on glass surface for extended periods of time, even at 35°C. Additional experiments suggest that external viral structures in direct contact with the environment are mostly involved in loss of virus infectivity.

GeneXpert (Cepheid) is the only WHO prequalified platform for hepatitis C virus (HCV) nucleic acid amplification testing that is suitable for point-of-care use in resource-limited contexts. However, its application is constrained by the lack of evidence on genotype 6 (GT6) HCV. We evaluated its field performance among a patient population in Cambodia predominantly infected with GT6. Between August and September 2017, we tested plasma samples obtained from consenting patients at Médecins Sans Frontières' HCV clinic at Preah Kossamak Hospital for HCV viral load (VL) using GeneXpert and compared its results to those obtained using COBAS AmpliPrep/Cobas TaqMan HCV Quantitative Test, v2.0 (Roche) at the Institut Pasteur du Cambodge. Among 769 patients, 77% of the seropositive patients (n = 454/590) had detectable and quantifiable VL using Roche and 43% (n = 195/454) were GT6. The sensitivity and specificity of GeneXpert against Roche were 100% (95% CI 99.2, 100.0) and 98.5% (95% CI 94.8, 99.8). The mean VL difference was -0.01 (95% CI -0.05, 0.02) log IU/mL for 454 samples quantifiable on Roche and -0.07 (95% CI -0.12, -0.02) log IU/mL for GT6 (n = 195). The limit of agreement (LOA) was -0.76 to 0.73 log IU/mL for all GTs and -0.76 to 0.62 log IU/mL for GT6. Twenty-nine GeneXpert results were outside the LOA. Frequency of error and the median turnaround time (TAT) for GeneXpert were 1% and 0 days (4 days using Roche). We demonstrated that the GeneXpert HCV assay has good sensitivity, specificity, quantitative agreement, and TAT in a real-world, resource-limited clinical setting among GT6 HCV patients.

BackgroundInfluenza A viruses have an envelope made of a lipid bilayer and two surface glycoproteins, the hemagglutinin and the neuraminidase. The structure of the virus is directly dependent on the genetic makeup of the viral genome except the glycosylation moieties and the composition of the lipid bilayer. They both depend on the host cell and are in direct contact with the environment, such as air or water. Virus survival is important for virus transmission from contaminated waters in the case of wild aquatic birds or from contaminated surface or air for humans.ObjectiveThe objective of this study was to check whether the origin species of the host cell has an influence on influenza A virus survival.MethodThe persistence in water at 35°C of viruses grown on either mammalian cells or avian cells and belonging to two different subtypes H1N1 and H5N1 was compared.ResultsBoth H5N1 and H1N1 viruses remained infectious for periods of time as long as 19–25 days, respectively. However, within the same subtype, viruses grown on mammalian cells were more stable in water at 35°C than their counterparts grown on avian cells, even for viruses sharing the same genetic background.ConclusionsThis difference in virus stability outside the host is probably connected to the nature of the lipid bilayer taken from the cell or to the carbohydrate side chains of the virus surface glycoproteins. Moreover, the long-lasting survival time might have a critical role in the ecology of influenza viruses, especially for avian viruses.

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Influenza A viruses (IAVs) are a major cause of infectious respiratory human diseases and their transmission is dependent upon the environment. However, the role of environmental factors on IAV survival outside the host still raises many questions. In this study, we used lentiviral pseudotypes to study the influence of the hemagglutinin protein in IAV survival. High-titered and cleaved influenza-based lentiviral pseudoparticles, through the use of a combination of two proteases (HAT and TMPRSS2) were produced. Pseudoparticles bearing hemagglutinin proteins derived from different H1N1, H3N2 and H5N1 IAV strains were subjected to various environmental parameters over time and tested for viability through single-cycle infectivity assays. We showed that pseudotypes with different HAs have different persistence profiles in water as previously shown with IAVs. Our results also showed that pseudotypes derived from H1N1 pandemic virus survived longer than those derived from seasonal H1N1 virus from 1999, at high temperature and salinity, as previously shown with their viral counterparts. Similarly, increasing temperature and salinity had a negative effect on the survival of the H3N2 and H5N1 pseudotypes. These results showed that pseudotypes with the same lentiviral core, but which differ in their surface glycoproteins, survived differently outside the host, suggesting a role for the HA in virus stability.

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Introduction We aimed to assess temporal changes in the presentation and survival of patients with hepatocellular carcinoma (HCC) in the northern Egypt region, one of the regions reporting the highest incidence of the disease globally. Methods We conducted a monocentric retrospective study. Patients presenting at the Damietta Oncology referral center between 2007 and 2019 with a diagnosed HCC were eligible. Individual, clinical and tumor characteristics at HCC diagnosis, including the Barcelona Clinic Liver Cancer (BCLC) staging, were retrieved from medical files and patients’ final vital status was ascertained by combining various data sources. Patients were divided into 2 groups based on diagnosis period: pre- and post-2014. Survival was analysed based on Kaplan–Meier curves and differences in restricted mean survival time (RMST). Results Data from 5097 patients (among 5210 eligible, 97.8%) were analyzed. We observed a significant trend toward HCC diagnosed at earlier stage in the post- vs pre-2014 period (BCLC stage 0/A or B: 37.2% vs 27.1%, p<10 −3 ). Overall patient’s survival after the HCC diagnosis was poor, with a median of 8.1 months. The BCLC staging system performed well in predicting survival. Despite a trend toward HCC diagnosed at earlier stages, we did not observe a significant improvement in survival over time. Overall, treatments offered in this medical center were in line with international guidelines, and 16.1% of the patients who received a curative treatment had an improved survival (30.7 months in median). However, HCC recurrence was frequent among patients cured for HCC, with a median time to recurrence of 22 months. Discussion Overall survival after HCC diagnosis in Egypt remains poor but is significantly improved by curative therapy. Despite a trend toward earlier diagnosis of HCC, we did not observe a general improvement in survival over time, which remains to be clearly understood.