The Failures of an Ideal COVID-19 Vaccine: A Simulation Study

Mapping Intimacies ◽

10.1101/2021.11.22.21266669 ◽

2021 ◽

Author(s):

Robert Joseph Kosinski

Keyword(s):

Vaccine Hesitancy ◽

First Year ◽

Sharp Drop ◽

Spreadsheet Model ◽

Long Duration ◽

Medium Level ◽

Case Rate ◽

Nonpharmaceutical Interventions ◽

Vaccine Distribution ◽

Ideal Vaccine

This paper simulates an ideal COVID-19 vaccine that confers immediate sterilizing immunity against all SARS-CoV-2 variants. The purpose was to explore how well this ideal vaccine could protect a population against common conditions (such as vaccine hesitancy) that might impair vaccine effectiveness. Simulations were done with an SEIRS spreadsheet model that ran two parallel subpopulations: one that accepted vaccination, and another that refused it. The two subpopulations could transmit infections to one another. Success was judged by the rate of new cases in the period from 1-5 years after the introduction of the vaccine. Under good conditions, including a small subpopulation that refused vaccination, rapid distribution of the vaccine, duration of vaccinal immunity longer than 12 months, good retention of interest in getting vaccinated after the first year, strict maintenance of nonpharmaceutical interventions (NPIs) such as masking, and new variants with R0s less than 4.0, the vaccine was able to end the epidemic. With violation of these conditions, the post-vaccine era futures ranged from endemic COVID at a low or medium level to rates of COVID cases worse than anything seen in the US up to late 2021. The most important conditions for keeping case rates low were a fast speed of vaccine distribution, a low percentage of the population that refuses vaccination, a long duration of vaccinal immunity, and continuing maintenance of NPIs after vaccination began. On the other hand, a short duration of vaccinal immunity, abandonment of NPIs, and new variants with a high R0 were powerful barriers to disease control. New variants with high R0s were particularly damaging, producing high case rates except when vaccination speed was unrealistically rapid. A recurring finding was that most disease afflicting the vaccinated population in these simulations originated in the unvaccinated population, and cutting off interaction with the unvaccinated population caused a sharp drop in the case rate of the vaccinated population. In conclusion, multiple common conditions can compromise the effectiveness of even an ideal vaccine.

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Correlation between Listening Anxiety and Listening Strategies of Chinese Postgraduate Students of Science and Engineering: A Case Study at SUES

International Journal of Learning and Development ◽

10.5296/ijld.v6i4.10123 ◽

2016 ◽

Vol 6 (4) ◽

Author(s):

Shengli Wang

Keyword(s):

Foreign Language ◽

First Year ◽

Chi Square ◽

Postgraduate Students ◽

Listening Anxiety ◽

Medium Level ◽

Chi Square Test ◽

Listening Proficiency ◽

Listening Strategies

<p>English listening is one of the five basic skills such as listening, speaking, reading, writing and translation that a Chinese postgraduate should acquire, and it is also the most significant one. In this study, 194 first-year postgraduate students at Shanghai University of Engineering Science were invited to report their strategies use and listening anxiety in the questionnaire with the 5-Likert Indirect Foreign Language Listening Strategies Scale and the 5-Likert Foreign Language Listening Anxiety Scale. The SPSS13.0 was used to analyze the descriptive statistics, reliability analysis, correlation analysis, Chi-square test and One-way ANOVA, which indicated a medium listening anxiety and a medium level of strategies use. Metacognitive strategies were more frequently used than social and affective strategies, the correlation between listening proficiency and listening anxiety was significantly negative, correlation between listening proficiency and indirect listening strategies was significantly positive, and that between indirect listening strategies and listening anxiety was significantly negative. Indirect listening strategies were useful to allay listening anxiety and would be incorporated into our normal classroom teaching.</p>

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Landslides after wildfire: initiation, magnitude, and mobility

Landslides ◽

10.1007/s10346-020-01506-3 ◽

2020 ◽

Vol 17 (11) ◽

pp. 2631-2641

Author(s):

Francis K. Rengers ◽

Luke A. McGuire ◽

Nina S. Oakley ◽

Jason W. Kean ◽

Dennis M. Staley ◽

...

Keyword(s):

Debris Flows ◽

Rainfall Intensity ◽

Ground Cover ◽

First Year ◽

Mass Wasting ◽

Soil Infiltration ◽

Infiltration Capacity ◽

The Past ◽

Long Duration ◽

Southwestern Usa

Abstract In the semiarid Southwestern USA, wildfires are commonly followed by runoff-generated debris flows because wildfires remove vegetation and ground cover, which reduces soil infiltration capacity and increases soil erodibility. At a study site in Southern California, we initially observed runoff-generated debris flows in the first year following fire. However, at the same site three years after the fire, the mass-wasting response to a long-duration rainstorm with high rainfall intensity peaks was shallow landsliding rather than runoff-generated debris flows. Moreover, the same storm caused landslides on unburned hillslopes as well as on slopes burned 5 years prior to the storm and areas burned by successive wildfires, 10 years and 3 years before the rainstorm. The landslide density was the highest on the hillslopes that had burned 3 years beforehand, and the hillslopes burned 5 years prior to the storm had low landslide densities, similar to unburned areas. We also found that reburning (i.e., two wildfires within the past 10 years) had little influence on landslide density. Our results indicate that landscape susceptibility to shallow landslides might return to that of unburned conditions after as little as 5 years of vegetation recovery. Moreover, most of the landslide activity was on steep, equatorial-facing slopes that receive higher solar radiation and had slower rates of vegetation regrowth, which further implicates vegetation as a controlling factor on post-fire landslide susceptibility. Finally, the total volume of sediment mobilized by the year 3 landslides was much smaller than the year 1 runoff-generated debris flows, and the landslides were orders of magnitude less mobile than the runoff-generated debris flows.

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The Kinetics of Anti-HLA Antibodies in the First Year after Kidney Transplantation: In Whom and When Should They Be Monitored?

Journal of Transplantation ◽

10.1155/2018/8316860 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Maria Cristina Ribeiro de Castro ◽

Erick A. Barbosa ◽

Renata P. Souza ◽

Fabiana Agena ◽

Patrícia S. de Souza ◽

...

Keyword(s):

Acute Rejection ◽

De Novo ◽

First Year ◽

Sharp Drop ◽

Hla Antibodies ◽

Single Antigen ◽

The Impact ◽

Kinetics Of ◽

Time Point ◽

Rejection Rates

The impact of the kinetics of the anti-HLA antibodies after KTx on the occurrence of acute rejection as well as the better time-point to monitor anti-HLA Abs after transplantation is not completely defined. This prospective study followed 150 patients over 12 months after transplantation. Serum IgG anti-HLA Abs were detected by single antigen beads after typing donors and recipients for loci A, B, C, DR, and DQ. Before KTx, 89 patients did not present anti-HLA Abs and 2% developed “de novo” Abs during the 1st year, 39 patients were sensitized without DSAs, and 13% developed DSA after surgery; all of them presented ABMR. Sensitized patients presented higher acute rejection rates (36.4% versus 13.5%, p<0.001), although 60% of the patients did not present ABMR. Patients, in whom DSA-MFI decreased during the first two weeks after surgery, did not develop ABMR. Those who sustained their levels presented a rate of 22% of ABMR. 85% of patients developed ABMR when MFIs increased early after transplantation (which occurred in 30% of the DSA positive patients). In the ABMR group, we observed an iDSA-MFI sharp drop on the fourth day and then an increase between the 7th and 14th POD, which suggests DSA should be monitored at this moment in sensitized patients for better ABMR prediction.

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Healthcare worker intentions to receive a COVID-19 vaccine and reasons for hesitancy: A survey of 16,158 health system employees on the eve of vaccine distribution

10.1101/2020.12.19.20248555 ◽

2020 ◽

Author(s):

Michelle N. Meyer ◽

Tamara Gjorgjieva ◽

Daniel Rosica

Keyword(s):

Health System ◽

Healthcare Workers ◽

Response Rate ◽

Vaccine Hesitancy ◽

Vaccine Acceptance ◽

Population Immunity ◽

Survey Results ◽

Acceptance Rates ◽

Vaccine Distribution ◽

To Receive

AbstractHealthcare workers (HCWs) have been recommended to receive first priority for limited COVID-19 vaccines. They have also been identified as potential ambassadors of COVID-19 vaccine acceptance, helping to ensure that sufficient members of a hesitant public accept COVID-19 vaccines to achieve population immunity. Yet HCWs themselves have shown vaccine hesitancy in other contexts and the few prior surveys of U.S. HCW intentions to receive a COVID-19 vaccine report acceptance rates of only 28% to 34%. However, it is unknown whether HCW acceptance remains low following mid-November announcements of the efficacy of the first COVID-19 vaccines and the issuance of two emergency use authorizations (EUA) in December. We report the results of a December 2020 survey (N = 16,158; response rate 61%) administered by a large Pennsylvania health system to determine the intentions of its employees to receive a vaccine when it is offered to them. In a mixed sample of individuals serving in patient-facing and other roles, 55% would decide to receive a COVID-19 vaccine when offered, 16.4% would not, and 28.5% reported being undecided. The distribution of responses varied little across hospital campuses, between those in patient-facing roles and other HCWs, or by area or department of work. The higher rate of COVID-19 vaccine acceptance we observe may reflect the framing and timing of our survey. Among hesitant respondents, an overwhelming majority (90.3%) reported concerns about unknown risks and insufficient data. Other commonly reported concerns included known side effects (57.4%) and wanting to wait until they see how it goes with others (44.4%). We observed a substantial increase in self-reported intent to receive a COVID-19 vaccine after an FDA advisory committee voted to recommend an EUA. Among respondents who completed the survey after that point in time, 79% intend to receive a COVID-19 vaccine (n = 1155). Although only suggestive, this trend offers hope that rates of COVID-19 vaccine acceptance may be higher among HCWs and, perhaps, the general public than more hypothetical survey results have indicated.

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Healthcare worker intentions to receive a COVID-19 vaccine and reasons for hesitancy: A survey of 16,158 health system employees on the eve of vaccine distribution

10.31234/osf.io/ge6uh ◽

2020 ◽

Author(s):

Michelle N. Meyer ◽

Tamara Gjorgjieva ◽

Daniel Rosica

Keyword(s):

Health System ◽

Healthcare Workers ◽

Response Rate ◽

Vaccine Hesitancy ◽

Vaccine Acceptance ◽

Population Immunity ◽

Survey Results ◽

Acceptance Rates ◽

Vaccine Distribution ◽

To Receive

Healthcare workers (HCWs) have been recommended to receive first priority for limited COVID-19 vaccines. They have also been identified as potential ambassadors of COVID-19 vaccine acceptance, helping to ensure that sufficient members of a hesitant public accept COVID-19 vaccines to achieve population immunity. Yet HCWs themselves have shown vaccine hesitancy in other contexts and the few prior surveys of U.S. HCW intentions to receive a COVID-19 vaccine report acceptance rates of only 28% to 34%. However, it is unknown whether HCW acceptance remains low following mid-November announcements of the efficacy of the first COVID-19 vaccines and the issuance of two emergency use authorizations (EUA) in December. We report the results of a December 2020 survey (N = 16,158; response rate 61%) administered by a large Pennsylvania health system to determine the intentions of its employees to receive a vaccine when it is offered to them. In a mixed sample of individuals serving in patient-facing and other roles, 55% would decide to receive a COVID-19 vaccine when offered, 16.4% would not, and 28.5% reported being undecided. The distribution of responses varied little across hospital campuses, between those in patient-facing roles and other HCWs, or by area or department of work. The higher rate of COVID-19 vaccine acceptance we observe may reflect the framing and timing of our survey. Among hesitant respondents, an overwhelming majority (90.3%) reported concerns about unknown risks and insufficient data. Other commonly reported concerns included known side effects (57.4%) and wanting to wait until they see how it goes with others (44.4%). We observed a substantial increase in self-reported intent to receive a COVID-19 vaccine after an FDA advisory committee voted to recommend an EUA. Among respondents who completed the survey after that point in time, 79% intend to receive a COVID-19 vaccine (n = 1155). Although only suggestive, this trend offers hope that rates of COVID-19 vaccine acceptance may be higher among HCWs and, perhaps, the general public than more hypothetical survey results have indicated.

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Vaccine breakthrough and the invasion dynamics of SARS-CoV-2 variants

10.1101/2021.12.13.21267725 ◽

2021 ◽

Author(s):

Chadi M Saad-Roy ◽

Simon A Levin ◽

Julia Rose Gog ◽

Jeremy Farrar ◽

Caroline E Wagner ◽

...

Keyword(s):

Vaccination Coverage ◽

Epidemiological Model ◽

Vaccine Hesitancy ◽

Invasion Dynamics ◽

Vaccination Rates ◽

Number Of Factors ◽

Potential Benefits ◽

Protection Against Infection ◽

Vaccine Distribution

Vaccination provides a powerful tool for mitigating and controlling the COVID-19 pandemic. However, a number of factors reduce these potential benefits. The first problem arises from heterogeneities in vaccine supply and uptake: from global inequities in vaccine distribution, to local variations in uptake derived from vaccine hesitancy. The second complexity is biological: though several COVID-19 vaccines offer substantial protection against infection and disease, 'breakthrough' reinfection of vaccinees (and subsequent retransmission from these individuals) can occur, driven especially by new viral variants. Here, using a simple epidemiological model, we show that the combination of infection of remaining susceptible individuals and breakthrough infections of vaccinees can have significant effects in promoting infection of invading variants, even when vaccination rates are high and onward transmission from vaccinees relatively weak. Elaborations of the model show how heterogeneities in immunity and mixing between vaccinated and unvaccinated sub-populations modulate these effects, underlining the importance of quantifying these variables. Overall, our results indicate that high vaccination coverage still leaves no room for complacency if variants are circulating that can elude immunity, even if this happens at very low rates.

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The Relationship between Metacognitive Reading Strategy Awareness and Reading Comprehension among freshman EFL Students, Ethiopia

Journal of English Language and Literature ◽

10.17722/jell.v10i3.399 ◽

2018 ◽

Vol 10 (3) ◽

pp. 1043-1050

Author(s):

Asalefew Mekuria Wudneh

Keyword(s):

Reading Comprehension ◽

Reading Strategies ◽

Pearson Correlation ◽

Reading Strategy ◽

Mean Value ◽

First Year ◽

Efl Learners ◽

Medium Level ◽

Efl Students ◽

Metacognitive Reading Strategies

The study was an attempt to investigate the level of awareness on Metacognitive reading strategies among first year Ethiopian EFL students. It also tried to figure out the possible relationship between Metacognitive reading strategies use and reading comprehension achievement. Ninety-four EFL learners participated in the study. Metacognitive reading strategy inventory and reading comprehension test were used to collect the data. The data were analyzed through descriptive statistics to determine the mean value of strategies employed by the learners. Moreover, Pearson correlation coefficient was used to discover the association between reading strategy use and reading comprehension achievement. According to the findings Ethiopian EFL learners ,were almost near to the lower limit (M=2.55,Sd.=0.34)line of medium level reading strategy users. Furthermore, the use of metacognitive reading strategy had weak correlation (r=0.21,p=0.039) with reading comprehension achievement. The possible cause of this could be lack of awareness on how to regulate and monitor reading comprehension.

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Preferences for COVID-19 vaccine distribution strategies in the US: A discrete choice survey

PLoS ONE ◽

10.1371/journal.pone.0256394 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0256394

Author(s):

Ingrid Eshun-Wilson ◽

Aaloke Mody ◽

Khai Hoan Tram ◽

Cory Bradley ◽

Alexander Sheve ◽

...

Keyword(s):

Service Delivery ◽

Discrete Choice ◽

Latent Class ◽

Vaccine Hesitancy ◽

Sampling Weights ◽

Public Health Response ◽

Vaccination Rates ◽

The Public ◽

The Us ◽

Vaccine Distribution

Background The COVID-19 vaccination campaign in the US has been immensely successful in vaccinating those who are receptive, further increases in vaccination rates however will require more innovative approaches to reach those who remain hesitant. Developing vaccination strategies that are modelled on what people want could further increase uptake. Methods and findings To inform COVID-19 vaccine distribution strategies that are aligned with public preferences we conducted a discrete choice experiment among the US public (N = 2,895) between March 15 to March 22, 2021. We applied sampling weights, evaluated mean preferences using mixed logit models, and identified latent class preference subgroups. On average, the public prioritized ease, preferring single to two dose vaccinations (mean preference: -0.29; 95%CI: -0.37 to -0.20), vaccinating once rather than annually (mean preference: -0.79; 95%CI: -0.89 to -0.70) and reducing waiting times at vaccination sites. Vaccine enforcement reduced overall vaccine acceptance (mean preference -0.20; 95%CI: -0.30 to -0.10), with a trend of increasing resistance to enforcement with increasing vaccine hesitancy. Latent class analysis identified four distinct preference phenotypes: the first prioritized inherent “vaccine features” (46.1%), the second were concerned about vaccine “service delivery” (8.8%), a third group desired “social proof” of vaccine safety and were susceptible to enforcement (13.2%), and the fourth group were “indifferent” to vaccine and service delivery features and resisted enforcement (31.9%). Conclusions This study identifies several critical insights for the COVID-19 public health response. First, identifying preference segments is essential to ensure that vaccination services meet the needs of diverse population subgroups. Second, making vaccination easy and promoting autonomy by simplifying services and offering the public choices (where feasible) may increase uptake in those who remain deliberative. And, third vaccine mandates have the potential to increase vaccination rates in susceptible groups but may simultaneously promote control aversion and resistance in those who are most hesitant.

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LESSONS FROM THE COVID-19 THIRD WAVE IN CANADA: THE IMPACT OF VARIANTS OF CONCERN AND SHIFTING DEMOGRAPHICS

10.1101/2021.08.27.21261857 ◽

2021 ◽

Author(s):

Finlay A McAlister ◽

Majid Nabipoor ◽

Anna Chu ◽

Douglas Lee ◽

Lynora Saxinger ◽

...

Keyword(s):

Age Groups ◽

Vaccine Hesitancy ◽

First Year ◽

Third Wave ◽

Wild Type ◽

Lengths Of Stay ◽

Younger Age ◽

Canadian Provinces ◽

Event Rates ◽

The Impact

Importance: With the emergence of more transmissible SARSCoV2 variants of concern (VOC), there is an urgent need for evidence about disease severity and the health care impacts of VOC in North America, particularly since a substantial proportion of the population have declined vaccination thus far. Objective: To examine 30day outcomes in Canadians infected with SARSCoV2 in the first year of the pandemic and to compare event rates in those with VOC versus wild type infection. Design: Retrospective cohort study using linked healthcare administrative datasets. Setting: Alberta and Ontario, the two Canadian provinces that experienced the largest third wave in the spring of 2021. Participants: All individuals with a positive SARSCoV2 reverse transcriptase polymerase chain reaction swab from March 1, 2020 until March 31, 2021, with genomic confirmation of VOC screen positive tests during February and March 2021 (wave 3). Exposure of Interest: VOC versus wild type SARSCoV2 Main Outcomes and Measures: All-cause hospitalizations or death within 30 days after a positive SARSCoV2 swab. Results: Compared to the 372,741 individuals with SARSCoV2 infection between March 2020 and January 2021 (waves 1 and 2 in Canada), there was a shift in transmission towards younger patients in the 104,232 COVID19 cases identified in wave 3. As a result, although third wave patients were more likely to be hospitalized (aOR 1.34 [1.29 to 1.39] in Ontario and aOR 1.53 [95%CI 1.41 to 1.65] in Alberta), they had shorter lengths of stay (median 5 vs. 7 days, p<0.001) and were less likely to die within 30 days (aOR 0.66 [0.60 to 0.71] in Ontario and aOR 0.74 [0.62 to 0.89] in Alberta). However, within the third wave, patients infected with VOC (91% Alpha) exhibited higher risks of death (aOR 1.52 [1.27 to 1.81] in Ontario and aOR 1.67 [1.13 to 2.48] in Alberta) and hospitalization (aOR 1.57 [1.47 to 1.69] in Ontario and aOR 1.88 [1.74 to 2.02] in Alberta) than those with wild-type SARSCoV2 infections during the same timeframe. Conclusions and Relevance: On a population basis, the shift towards younger age groups as the COVID19 pandemic has evolved translates into more hospitalizations but shorter lengths of stay and lower mortality risk than seen in the first 10 months of the pandemic in Canada. However, on an individual basis, infection with a VOC is associated with a higher risk of hospitalization or death than the original wild type SARSCoV2; this is important information to address vaccine hesitancy given the increasing frequency of VOC infections now.

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