Modelling an optimum vaccination strategy against ZIKA virus for outbreak use

AbstractWe present a model to optimise a vaccination campaign aiming to prevent or to curb a Zika virus outbreak. We show that the optimum vaccination strategy to reduce the number of cases by a mass vaccination campaign should start when the Aedes mosquitoes' density reaches the threshold of 1.5 mosquitoes per humans, the moment the reproduction number crosses one. The maximum time it is advisable to wait for the introduction of a vaccination campaign is when the first ZIKV case is identified, although this would not be as effective to minimise the number of infections as when the mosquitoes' density crosses the critical threshold. This suboptimum strategy, however, would still curb the outbreak. In both cases, the catch up strategy should aim to vaccinate at least 25% of the target population during a concentrated effort of 1 month immediately after identifying the threshold. This is the time taken to accumulate the herd immunity threshold of 56.5%. These calculations were done based on theoretical assumptions that vaccine implementation would be feasible within a very short time frame.

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Seroprevalence of SARS-CoV-2 Infection in Cincinnati Ohio USA from August to December 2020

10.1101/2021.03.11.21253263 ◽

2021 ◽

Author(s):

Greg Davis ◽

Allen J. York ◽

Willis Clark Bacon ◽

Lin Suh-Chin ◽

Monica Malone McNeal ◽

...

Keyword(s):

Vaccination Campaign ◽

Herd Immunity ◽

The United States ◽

Time Frame ◽

Spike Protein ◽

Ohio River ◽

Igg Antibody ◽

Past Infection ◽

Viral Neutralization ◽

Antibody Positivity

AbstractThe world is currently in a pandemic of COVID-19 (Coronavirus disease-2019) caused by a novel positive-sense, single-stranded RNA β-coronavirus referred to as SARS-CoV-2. Fortunately, most infected individuals recover and are then resistant to re-infection for a period, indicating that a vaccination approach can be successful. Elucidation of rates of past SARS-CoV-2 infection within select regions across the United States of America (USA) will help direct vaccination efforts and together will inform our approach towards achieving herd immunity. Here we investigated rates of SARS-CoV-2 infection in the greater Cincinnati, Ohio, USA metropolitan area from August to December 2020, just prior to initiation of the national vaccination program. Examination of 9,550 adult blood donor volunteers for serum IgG antibody positivity against the SARS-CoV-2 Spike protein showed an overall prevalence of 8.40%, measured as 7.56% in the first 58 days of this time frame, versus a significant increase to 9.24% in the last 58 days, and a final rate of 12.86% in December 2020. Approximately 56% of Spike seropositive individuals also had immunoreactivity against the receptor binding domain (RBD) within the Spike protein, which is associated with viral neutralization. Males and females in the Cincinnati area showed nearly identical rates of past infection, and rates among Hispanics, African Americans and Caucasians were not significantly different. Interestingly, donors under 30 years of age had the highest rates of past infection, while those over 60 had the lowest. Geographic analysis showed that the West side of Cincinnati had a rate of 9.63% versus 8.13% on the East side (demarcated by Interstate-75), while the adjoining area of Kentucky was 7.04% (as demarcated by the Ohio River). These results among healthy blood donors will be critical in calculating the time needed to achieve regional herd immunity in conjunction with the national vaccination campaign.

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Understanding protection from SARS-CoV-2 using metabolomics

Scientific Reports ◽

10.1038/s41598-021-93260-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Elettra Barberis ◽

Elia Amede ◽

Matteo Tavecchia ◽

Emilio Marengo ◽

Micol G. Cittone ◽

...

Keyword(s):

Vaccination Campaign ◽

Herd Immunity ◽

Antibacterial Properties ◽

Good Health ◽

Metabolic Phenotype ◽

Public Healthcare ◽

Blood Collection ◽

Serum Samples ◽

Defensive Role ◽

Mass Vaccination Campaign

AbstractThe COVID-19 pandemic is still raging in most countries. Although the recent mass vaccination campaign has opened a new chapter in the battle against SARS-CoV-2, the world is still far from herd immunity. There is an urgent need to identify healthy people at high risk of contracting COVID-19, as well as supplements and nutraceuticals that can reduce the risk of infection or mitigate symptoms. In the present study, a metabolic phenotype that could protect individuals from SARS-CoV-2 infection or predispose them to developing COVID-19 was investigated. Untargeted metabolomics was performed on serum samples collected from 51 healthcare workers who were in good health at the beginning of the COVID-19 outbreak in Italy, and who were later exposed to the same risk of developing COVID-19. Half of them developed COVID-19 within three weeks of the blood collection. Our results demonstrate the presence of a specific signature associated with protection from SARS-CoV-2. Circulating monolaurin, which has well-known antiviral and antibacterial properties, was higher in protected subjects, suggesting a potential defensive role against SARS-CoV-2 infection; thus, dietary supplements could boost the immune system against this infection. In addition, our data demonstrate that people with higher levels of cholesterol are at higher risk of developing COVID-19. The present study demonstrates that metabolomics can be of great help for developing personalized medicine and for supporting public healthcare strategies. Studies with larger cohorts of subjects are necessary to confirm our findings.

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Designing a vaccination strategy against dengue

Revista do Instituto de Medicina Tropical de São Paulo ◽

10.1590/s0036-46652012000700008 ◽

2012 ◽

Vol 54 (suppl 18) ◽

pp. 18-21 ◽

Cited By ~ 6

Author(s):

Marcos Amaku ◽

Laurent Coudeville ◽

Eduardo Massad

Keyword(s):

Vaccination Campaign ◽

Vaccination Strategy ◽

Mass Vaccination ◽

Dengue Vaccine ◽

Force Of Infection ◽

Childhood Infections ◽

Immunization Programme ◽

Mass Vaccination Campaign ◽

Northeastern State ◽

The City

In this work we propose a mathematical approach to estimate the dengue force of infection, the average age of dengue first infection, the optimum age to vaccinate children against dengue in a routine fashion and the optimum age interval to introduce the dengue vaccine in a mass vaccination campaign. The model is based on previously published models for vaccination against other childhood infections, which resulted in actual vaccination programmes in Brazil. The model was applied for three areas of distinct levels of endemicity of the city of Recife in Northeastern State of Pernambuco, Brazil. Our results point to an optimal age to introduce the dengue vaccine in the routine immunization programme at two years of age and an age interval to introduce a mass vaccination between three and 14 years of age.

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Predicting the impact of measles vaccination in England and Wales: model validation and analysis of policy options

Epidemiology and Infection ◽

10.1017/s0950268800057976 ◽

1995 ◽

Vol 114 (2) ◽

pp. 319-344 ◽

Cited By ~ 68

Author(s):

H. R. Babad ◽

D. J. Nokes ◽

N. J. Gay ◽

E. Miller ◽

P. Morgan-Capner ◽

...

Keyword(s):

Vaccine Coverage ◽

Case Reports ◽

Vaccination Campaign ◽

Herd Immunity ◽

Vaccination Strategy ◽

School Age Children ◽

Policy Options ◽

England And Wales ◽

Measles Vaccination ◽

The Impact

SummaryMeasles incidence in England and Wales has fallen to an all-time low. Attention is now focused on preventing local outbreaks, and, in the long run, on the elimination of indigenous measles. A realistic age-structured (RAS) mathematical model of measles transmission is used to reconstruct the impact of measles vaccination in England and Wales from 1968 to the present and to evaluate the merits of future policy options. In general, the predictions of the model show good agreement with long-term age stratified case reports and seroprevalence surveys. The model underestimates the proportion of cases that are notified in 0–2-year-old children. However, recent work suggests a high degree of misdiagnosis in this age group. Projections on the basis of the existing vaccination strategy in the UK suggest that the present level of measles vaccine coverage will be insufficient to eliminate small seasonal outbreaks of measles. This result is, however, sensitive to the assumed level of vaccine efficacy. Explorations of a variety of changes to current vaccination strategy favour a 2-dose schedule with the second dose administered at age 4 years irrespective of vaccination history. A vaccination campaign in school-age children, to reduce deficits in herd immunity, would accelerate progress towards measles elimination.

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UK measles outbreak in non-immune anthroposophic communities: the implications for the elimination of measles from Europe

Epidemiology and Infection ◽

10.1017/s0950268899004525 ◽

2000 ◽

Vol 125 (2) ◽

pp. 377-383 ◽

Cited By ~ 45

Author(s):

B. HANRATTY ◽

T. HOLT ◽

E. DUFFELL ◽

W. PATTERSON ◽

M. RAMSAY ◽

...

Keyword(s):

Measles Virus ◽

Vaccination Campaign ◽

Herd Immunity ◽

Postal Questionnaire ◽

Vaccine Uptake ◽

High Coverage ◽

The North ◽

Measles Outbreak ◽

Mass Vaccination Campaign ◽

The Uk

We describe the epidemiology of the first nationwide outbreak of measles infection in the UK since the implementation of a mass vaccination campaign. Notifications of infectious diseases, interview and postal questionnaire identified 293 clinical cases, 138 of which were confirmed by salivary IgM, measles virus isolation and PCR. Twelve were epidemiologically linked to confirmed cases. The outbreak began in London, after contact with measles infection probably imported from Italy. Measles genotyping determined by sequence analysis confirmed spread to other unimmunized anthroposophic communities in the north, south west and south coast of England. Only two cases had been vaccinated against measles infection, and 90% of cases were aged under 15 years. Measles virus can selectively target non-immune groups in countries with high vaccine uptake and broader herd immunity. Without harmonization of vaccination policies and uniform high coverage across Europe, the importation and spread of measles virus amongst non-immune groups may prevent the elimination of measles.

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A spatial vaccination strategy to reduce the risk of vaccine-resistant variants

10.21203/rs.3.rs-969637/v1 ◽

2021 ◽

Author(s):

Xiyun Zhang ◽

Gabriela Lobinska ◽

Michal Feldman ◽

Eddie Dekel ◽

Martin Nowak ◽

...

Keyword(s):

Vaccination Campaign ◽

Herd Immunity ◽

Vaccination Strategy ◽

World Population ◽

Global Risk ◽

Resistant Variant ◽

Infected People ◽

Vaccination Rates ◽

Population Immunity ◽

Fitness Advantage

Abstract The process of vaccinating the world population against COVID-19 is expected to take well over a year to complete. As vaccination progresses and population immunity increases, a counteracting relaxation of social distancing measures is observed. The result will be a prolonged period of high disease prevalence combined with a fitness advantage for vaccine-resistant variants, implying a considerably increased probability that a resistant variant will spread in the population. In this paper we propose a spatial vaccination strategy that has the potential to dramatically reduce this risk. Instead of spreading the vaccination effort equally throughout a country, distinct geographic regions of the country are sequentially vaccinated, quickly bringing each to effective herd immunity. Regions with high vaccination rates will then have low infection rates and vice versa. Since people primarily interact with others in their own region, spatial vaccination will reduce the number of encounters between infected people (the source of mutations) and vaccinated people (who facilitate the spread of vaccine-resistant strains). Thus with proper logistic preparations, a spatial vaccination campaign could be highly effective in reducing the global risk of vaccine-resistant variants.

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Zeitstrukturen im Jazz

Zeitschrift für Ästhetik und Allgemeine Kunstwissenschaft ◽

10.28937/1000106230 ◽

2014 ◽

Vol 59 (1) ◽

pp. 79-92

Author(s):

Alexander Becker

Keyword(s):

Large Scale ◽

Large Scale Structure ◽

Time Frame ◽

Scale Structure ◽

Classical Form ◽

Jazz Music ◽

The Moment

Wie erlebt der Hörer Jazz? Bei dieser Frage geht es unter anderem um die Art und Weise, wie Jazz die Zeit des Hörens gestaltet. Ein an klassischer Musik geschultes Ohr erwartet von musikalischer Zeitgestaltung, den zeitlichen Rahmen, der durch Anfang und Ende gesetzt ist, von innen heraus zu strukturieren und neu zu konstituieren. Doch das ist keine Erwartung, die dem Jazz gerecht wird. Im Jazz wird der Moment nicht im Hinblick auf ein Ziel gestaltet, das von einer übergeordneten Struktur bereitgestellt wird, sondern so, dass er den Bewegungsimpuls zum nächsten Moment weiterträgt. Wie wirkt sich dieses Prinzip der Zeitgestaltung auf die musikalische Form im Großen aus? Der Aufsatz untersucht diese Frage anhand von Beispielen, an denen sich der Weg der Transformation von einer klassischen zu einer dem Jazz angemessenen Form gut nachverfolgen lässt.<br><br>How do listeners experience Jazz? This is a question also about how Jazz music organizes the listening time. A classically educated listener expects a piece of music to structure, unify and thereby re-constitute the externally given time frame. Such an expectation is foreign to Jazz music which doesn’t relate the moment to a goal provided by a large scale structure. Rather, one moment is carried on to the next, preserving the stimulus potentially ad infinitum. How does such an organization of time affect the large scale form? The paper tries to answer this question by analyzing two examples which permit to trace the transformation of a classical form into a form germane to Jazz music.

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COVID-19 Vaccine Intention among Healthcare Workers in Saudi Arabia: A Cross-Sectional Survey

Vaccines ◽

10.3390/vaccines9080835 ◽

2021 ◽

Vol 9 (8) ◽

pp. 835

Author(s):

Mohammed Noushad ◽

Mohammad Zakaria Nassani ◽

Anas B. Alsalhani ◽

Pradeep Koppolu ◽

Fayez Hussain Niazi ◽

...

Keyword(s):

Saudi Arabia ◽

Healthcare System ◽

Healthcare Workers ◽

Vaccine Coverage ◽

Vaccination Campaign ◽

Herd Immunity ◽

Positive Sign ◽

Cross Sectional Survey ◽

Cross Sectional ◽

Public Health Strategies

The COVID-19 pandemic has caused largescale morbidity and mortality and a tremendous burden on the healthcare system. Healthcare workers (HCWs) require adequate protection to avoid onward transmission and minimize burden on the healthcare system. Moreover, HCWs can also influence the general public into accepting the COVID-19 vaccine. Therefore, determining COVID-19 vaccine intention among HCWs is of paramount importance to plan tailor-made public health strategies to maximize vaccine coverage. A structured questionnaire was administered in February and March 2021 among HCWs in Saudi Arabia using convenience sampling, proceeding the launch of the vaccination campaign. HCWs from all administrative regions of Saudi Arabia were included in the study. In total, 674 out of 1124 HCWs responded and completed the survey (response rate 59.9%). About 65 percent of the HCWs intended to get vaccinated. The intention to vaccinate was significantly higher among HCWs 50 years of age or older, Saudi nationals and those who followed the updates about COVID-19 vaccines (p < 0.05). The high percentage (26 percent) of those who were undecided in getting vaccinated is a positive sign. As the vaccination campaign gathers pace, the attitude is expected to change over time. Emphasis should be on planning healthcare strategies to convince the undecided HCWs into accepting the vaccine in order to achieve the coverage required to achieve herd immunity.

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Modelling the impact of delaying vaccination against SARS-CoV-2 assuming unlimited vaccine supply

Theoretical Biology and Medical Modelling ◽

10.1186/s12976-021-00143-0 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Marcos Amaku ◽

Dimas Tadeu Covas ◽

Francisco Antonio Bezerra Coutinho ◽

Raymundo Soares Azevedo ◽

Eduardo Massad

Keyword(s):

Mathematical Model ◽

Vaccination Campaign ◽

Vaccination Rate ◽

Sao Paulo ◽

The State ◽

São Paulo ◽

Health Authorities ◽

The World ◽

The Moment ◽

The Impact

Abstract Background At the moment we have more than 177 million cases and 3.8 million deaths (as of June 2021) around the world and vaccination represents the only hope to control the pandemic. Imperfections in planning vaccine acquisition and difficulties in implementing distribution among the population, however, have hampered the control of the virus so far. Methods We propose a new mathematical model to estimate the impact of vaccination delay against the 2019 coronavirus disease (COVID-19) on the number of cases and deaths due to the disease in Brazil. We apply the model to Brazil as a whole and to the State of Sao Paulo, the most affected by COVID-19 in Brazil. We simulated the model for the populations of the State of Sao Paulo and Brazil as a whole, varying the scenarios related to vaccine efficacy and compliance from the populations. Results The model projects that, in the absence of vaccination, almost 170 thousand deaths and more than 350 thousand deaths will occur by the end of 2021 for Sao Paulo and Brazil, respectively. If in contrast, Sao Paulo and Brazil had enough vaccine supply and so started a vaccination campaign in January with the maximum vaccination rate, compliance and efficacy, they could have averted more than 112 thousand deaths and 127 thousand deaths, respectively. In addition, for each month of delay the number of deaths increases monotonically in a logarithmic fashion, for both the State of Sao Paulo and Brazil as a whole. Conclusions Our model shows that the current delay in the vaccination schedules that is observed in many countries has serious consequences in terms of mortality by the disease and should serve as an alert to health authorities to speed the process up such that the highest number of people to be immunized is reached in the shortest period of time.

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Rotavirus Vaccination of Infants Delayed and Limited within the National Immunization Programme in the Netherlands: An Opportunity Lost

Vaccines ◽

10.3390/vaccines9020144 ◽

2021 ◽

Vol 9 (2) ◽

pp. 144

Author(s):

Florian Zeevat ◽

Evgeni Dvortsin ◽

Abrham Wondimu ◽

Jan C. Wilschut ◽

Cornelis Boersma ◽

...

Keyword(s):

High Risk ◽

The Netherlands ◽

Herd Immunity ◽

Vaccination Strategy ◽

Quality Adjusted Life Year ◽

High Risk Group ◽

Universal Vaccination ◽

Birth Cohorts ◽

Rotavirus Vaccination ◽

Immunization Programme

In this study, we estimated the benefits of rotavirus vaccination for infants had the rotavirus vaccine been introduced in the Netherlands as of its market authorization in 2006. An age-structured, deterministic cohort model was developed to simulate different birth cohorts over a period of 15 years from 2006 until 2021, comparing both universal and targeted high-risk group vaccination to no vaccination. Different scenarios for the duration of protection (5 or 7 years) and herd immunity (only for universal vaccination) were analyzed. All birth cohorts together included 2.6 million infants, of which 7.9% were high-risk individuals, and an additional 13.2 million children between 1–15 years born prior to the first cohort in 2006. The costs and health outcomes associated with rotavirus vaccination were calculated per model scenario and discounted at 4% and 1.5%, respectively. Our analysis reveals that, had rotavirus vaccination been implemented in 2006, it would have prevented 356,800 (51% decrease) and 32,200 (5% decrease) cases of rotavirus gastroenteritis after universal and targeted vaccination, respectively. Over the last 15 years, this would have led to significant avoided costs and quality-adjusted life year losses for either vaccination strategy with the most favorable outcomes for universal vaccination. Clearly, an opportunity has been lost.

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