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111.
As of late 2019, the outbreak of novel coronavirus disease (COVID-19) –that started in China– has rapidly afflicted all over the world. The COVID-19 pandemic has challenged health-care facilities to provide optimal care. In this context, cancer care requires special attention because of its peculiar status by including patients who are commonly immunocompromised and treatments that are often highly toxic. In this review article, we have classified the main impacts of the COVID-19 pandemic on oncology practices –followed by their solutions– into ten categories, including impacts on (1) health care providers, (2) medical equipment, (3) access to medications, (4) treatment approaches, (5) patients’ referral, (6) patients’ accommodation, (7) patients’ psychological health, (8) cancer research, (9) tumor board meetings, and (10) economic income of cancer centers. The effective identification and management of all these challenges will improve the standards of cancer care over the viral pandemic and can be a practical paradigm for possible future crises.  相似文献   
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Background

In spring 2020, U.S. universities closed campuses to limit the transmission of COVID-19, resulting in an abrupt change in residence, reductions in social interaction, and in many cases, movement away from a heavy drinking culture. The present mixed-methods study explores COVID-19-related changes in college student drinking. We characterize concomitant changes in social and location drinking contexts and describe reasons attributed to changes in drinking.

Methods

We conducted two studies of the impact of the COVID-19 pandemic on drinking behavior, drinking context, and reasons for both increases and decreases in consumption among college students. Study 1 (qualitative) included 18 heavy-drinking college students (Mage = 20.2; 56% female) who completed semi-structured interviews. Study 2 (quantitative) included 312 current and former college students who reported use of alcohol and cannabis (Mage = 21.3; 62% female) and who completed an online survey.

Results

In both studies, COVID-19-related increases in drinking frequency were accompanied by decreases in quantity, heavy drinking, and drunkenness. Yet, in Study 2, although heavier drinkers reduced their drinking, among non-heavy drinkers several indices of consumption increased or remained stable . Both studies also provided evidence of reductions in social drinking with friends and roommates and at parties and increased drinking with family. Participants confirmed that their drinking decreased due to reduced social opportunities and/or settings, limited access to alcohol, and reasons related to health and self-discipline. Increases were attributed to greater opportunity (more time) and boredom and to a lesser extent, lower perceived risk of harm and to cope with distress.

Conclusion

This study documents COVID-19-related changes in drinking among college student drinkers that were attributable to changes in context, particularly a shift away from heavy drinking with peers to lighter drinking with family. Given the continued threat of COVID-19, it is imperative for researchers, administrators, and parents to understand these trends as they may have lasting effects on college student drinking behaviors.
  相似文献   
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Background

Immune responses to novel pandemic influenza vaccines may be influenced by previous exposure to antigenically similar seasonal strains.

Methods

An open-label, randomized, phase I/II study was conducted to assess the immunogenicity and safety of a non-adjuvanted, inactivated whole-virus H1N1 A/California/07/2009 vaccine. 408 subjects were stratified by age (18–59 and >60 years) and randomized 1:1 to receive two vaccinations with either 3.75 or 7.5 μg hemagglutinin antigen 21 days apart. Safety, immunogenicity and the influence of seasonal influenza vaccination and antibody cross-reactivity with a seasonal H1N1 strain was assessed.

Results

A single vaccination with either dose induced substantial increases in H1N1 A/California/07/2009 hemagglutination inhibition (HI) and neutralizing (MN) antibody titers in both adult and elderly subjects. A single 7.5 μg dose induced seroprotection rates of 86.9% in adults and 75.2% in elderly subjects. Two 7.5 μg vaccinations induced seroprotection rates in adult and elderly subjects of 90.9% and 89.1%, respectively. The robust immune response to vaccination was confirmed by analyses of neutralizing antibody titers. Both HI and MN antibodies persisted for ≥6 months post-vaccination. Between 34% and 49% of subjects had seroprotective levels of H1N1 A/California/07/2009 antibodies at baseline. Higher baseline HI titers were associated with receipt of the 2008–09 or 2009–10 seasonal influenza vaccine. High baseline A/California/07/2009 neutralizing antibody titers were also associated with high baseline titers against A/New Caledonia/20/99, a seasonal H1N1 strain which circulated and was included in the seasonal vaccine from 2000–01 to 2006–07. Pre-adsorption with A/H1N1/New Caledonia/20/99 antigen reduced A/H1N1/California/07/2009 baseline titers in 55% of tested sera. The vaccine was well tolerated with low rates of fever.

Conclusions

A whole-virus H1N1 A/California/07/2009 vaccine was safe and well tolerated and a single dose induced substantial immune responses similar to seasonal influenza vaccines, probably due to immunological priming by previous seasonal influenza vaccines or infections.  相似文献   
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Background

Concern arose in 2010 that reactogenicity, particularly febrile seizures, to influenza A/H1N1-containing 2010–2011 trivalent seasonal inactivated influenza vaccine (TIV) could occur in young children who had been previously immunized and/or infected with the pandemic strain. We conducted a pre-season study of 2010–2011 TIV safety and immunogenicity in children 12–59 months of age to inform public health decision making.

Methods

Children immunized with 1 or 2 doses of the pandemic vaccine, with or without the 2009–10 TIV, received 1 or 2 doses of 2010–11 TIV in an observational, multicentre Canadian study. Standard safety monitoring was enhanced by a telephone call at ∼24 h post-TIV when adverse events were expected to peak. Summary safety reports were rapidly reported to public health before the launch of public programs. TIV immunogenicity was assessed day 0, and 21 days after final vaccination. Clinical Trials Registration NCT01180621.

Results

Among 207 children, a general adverse event was reported by 60.9% of children post-dose one and by 58.3% post-dose two. Only severe fever (>38.5 °C) was more common in two-dose compared to one dose recipients (16.7%, n = 4 v. 1.0%, n = 2). At baseline 99.0% of participants had A/H1N1 hemagglutinin inhibition (HAI) titers ≥10, and 85.5% had a protective titer of ≥40 (95% CI 80.0, 90.0). Baseline geometric mean titers (GMT) were higher in recipients of a 2-dose schedule of pandemic vaccine compared to one-dose recipients: 153.1 (95% CI 126.2, 185.7) v. 78.8 ((58.1, 106.8, p < 0.001). At 21 days, all regulatory criteria for influenza vaccine immunogenicity were exceeded for A/H1N1 and H3N2, but responses to the B antigen were poor. No correlations between reactogenicity and either baseline high influenza titers or serologic response to revaccination were evident.

Conclusions

Infants and toddlers who received AS03-adjuvanted A/H1N1 2009 vaccine up to 11 months earlier retained high titers in the subsequent season but re-exposure to A/H1N1 2009 antigen in TIV resulted in no unusual adverse effects and 100% were sero-protected for A/H1N1 after receipt of the 2010–11 TIV.  相似文献   
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Haemagglutination-inhibition (HI) and virus neutralisation (VN) assays are routinely applied to evaluate influenza vaccine immunogenicity for regulatory approval. Despite their frequent use both assays are currently only poorly standardised causing considerable inter-laboratory variation of serological results that is particularly evident for pandemic influenza vaccines. The present study was conducted in association with the European Medicines Agency (EMA) to directly compare assay variability between vaccine manufacturer's and European regulatory agency's laboratories in an influenza pandemic scenario. To this end, a defined subset of H1N1 pdm clinical trial sera from all manufacturers that had applied at EMA for approval of pandemic H1N1 vaccines were re-tested by the National Institute for Biological Standards and Control (for HI) and the Paul Ehrlich Institute (for VN). Comparative analysis of test results determined for almost 2000 serum samples revealed a marked inter-laboratory variation for HI titres (up to 5.8-fold) and even more for neutralisation titres (up to 7.0-fold). When the absolute titres were adjusted relative to the calibrated International Antibody Standard 09/194 variation was drastically reduced and acceptable agreement of results from different laboratories could be achieved. Hence, inclusion of an appropriate calibrated antibody standard for adjustment of original titres is a powerful tool to substantially increase reproducibility of serological results from different laboratories and to significantly improve regulatory evaluation of influenza vaccine efficacy.  相似文献   
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Zhang J  While AE  Norman IJ 《Vaccine》2012,30(32):4813-4819
This study aimed to estimate the vaccination coverage against the pandemic H1N1 influenza in a group of nurses and determine the factors associated with their vaccination behaviours. An anonymous, self-administered questionnaire was distributed to a convenience sample of nurses who were enrolled on continuing professional education courses in a university in London. The survey response rate was 77.7% (n=522). A total of 172 (35.2%) nurses reported receiving the pandemic H1N1 vaccine in the 2009-2010 influenza season and only 22.3% of them had the intent to accept the vaccine in the next season. Compared to nurses with low knowledge scores, those with high knowledge scores were more likely to receive the pandemic H1N1 vaccine (p=0.017), recommend the vaccine to their patients (p=0.003), and have the willingness to recommend vaccination to patients in the future (p=0.009). There was a higher vaccination rate among nurses with higher risk perception scores than with lower scores (p=0.001). A small, positive correlation between H1N1 knowledge and risk perception scores was identified (p<0.001) indicating that a high knowledge level was associated with high levels of risk perception. More male nurses received the H1N1 vaccine than females (p<0.001) and there were a significant differences in the uptake among nurses from different clinical specialty groups (p<0.001). About half of the vaccinated nurses reported the intent to be vaccinated again but only 8.1% of the unvaccinated nurses had the intent to receive the vaccine in the next season (p<0.001). The pandemic H1N1 2009 influenza vaccination coverage among this nurse sample was sub-optional. Lack of knowledge and risk perception were predictors associated with the nurses' vaccination behaviours. The identified knowledge items should be addressed in future vaccination campaigns. The hindrances associated with continuing vaccination decision-making and factors contributing to the different vaccination coverage among clinical specialty groups require further exploration.  相似文献   
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