scholarly journals Counting the Costs of COVID-19: Why Future Treatment Option Values Matter

2020 ◽  
Vol 7 (6) ◽  
pp. 36
Author(s):  
Adrian Kent
Keyword(s):  
Herd Immunity ◽  
Life Quality ◽  
Quality Adjusted Life Year ◽  
Recent Analysis ◽  
Effective Vaccine ◽  
Medical Interventions ◽  
Social Interventions ◽  
The United Kingdom ◽  
Cast Doubt

I critique a recent analysis (Miles, Stedman & Heald, 2020) of COVID-19 lockdown costs and benefits, focussing on the United Kingdom (UK). Miles et al. (2020) argue that the March-June UK lockdown was more costly than the benefit of lives saved, evaluated using the NICE threshold of £30000 for a quality-adjusted life year (QALY) and that the costs of a lockdown for 13 weeks from mid-June would be vastly greater than any plausible estimate of the benefits, even if easing produced a second infection wave causing over 7000 deaths weekly by mid-September.   I note here two key problems that significantly affect their estimates and cast doubt on their conclusions. Firstly, their calculations arbitrarily cut off after 13 weeks, without costing the epidemic end state. That is, they assume indifference between mid-September states of 13 or 7500 weekly deaths and corresponding infection rates. This seems indefensible unless one assumes that (a) there is little chance of any effective vaccine or improved medical or social interventions for the foreseeable future, (b) notwithstanding temporary lockdowns, COVID-19 will very likely propagate until herd immunity. Even under these assumptions it is very questionable. Secondly, they ignore the costs of serious illness, possible long-term lowering of life quality and expectancy for survivors. These are uncertain, but plausibly at least as large as the costs in deaths.In summary, policy on tackling COVID-19 cannot be rationally made without estimating probabilities of future medical interventions and long-term illness costs. More work on modelling these uncertainties is urgently needed.

scholarly journals Long-term and herd immunity against SARS-CoV-2: implications from current and past knowledge

2020 ◽  
Vol 78 (3) ◽  
Author(s):  
Eleni Papachristodoulou ◽  
Loukas Kakoullis ◽  
Konstantinos Parperis ◽  
George Panos
Keyword(s):  
Immune Response ◽  
Herd Immunity ◽  
Effective Vaccine ◽  
Natural Immunity ◽  
Infection Rates ◽  
Mutant Strains ◽  
Current Infection ◽  
The Stability ◽  
Urgent Necessity

ABSTRACT Effective herd immunity against SARS-CoV-2 will be determined on many factors: the percentage of the immune population, the length and effectiveness of the immune response and the stability of the viral epitopes. The required percentage of immune individuals has been estimated to be 50–66% of the population which, given the current infection rates, will take long to be achieved. Furthermore, data from SARS-CoV suggest that the duration of immunity may not be sufficiently significant, while the immunity response against SARS-CoV-2 may not be efficiently effective in all patients, as relapses have already been reported. In addition, the development of mutant strains, which has already been documented, can cause the reemergence of the epidemic. In conclusion, the development of an effective vaccine is an urgent necessity, as long-term natural immunity to SARS-CoV-2 may not be sufficient for the control of the current and future outbreaks.

scholarly journals Calibrating an SIR model for South Korea COVID-19 infections and predicting vaccination impact

2021 ◽  
Author(s):  
Brandon Pae
Keyword(s):  
South Korea ◽  
Vaccination Coverage ◽  
Herd Immunity ◽  
Sir Model ◽  
Transmission Dynamics ◽  
Effective Vaccine ◽  
Epidemiological Models ◽  
Policy Decisions

In the span of 1.5 years, COVID-19 has caused more than 4 million deaths worldwide. To prevent such a catastrophe from reoccurring, it is necessary to test and refine current epidemiological models that impact policy decisions. Thus, we developed a deterministic SIR model to examine the long-term transmission dynamics of COVID-19 in South Korea. Using this model, we analyzed how vaccines would affect the number of cases. We found that a 70% vaccination coverage with a 100% effective vaccine would effectively eliminate the number of cases and herd immunity would have been obtained approximately 85 days after February 15 had there not been a reintroduction of cases.

scholarly journals Updated Postlicensure Surveillance of the Meningococcal C Conjugate Vaccine in England and Wales: Effectiveness, Validation of Serological Correlates of Protection, and Modeling Predictions of the Duration of Herd Immunity

2010 ◽  
Vol 17 (5) ◽  
pp. 840-847 ◽  
Author(s):  
Helen Campbell ◽  
Nick Andrews ◽  
Ray Borrow ◽  
Caroline Trotter ◽  
Elizabeth Miller
Keyword(s):  
Confidence Interval ◽  
Herd Immunity ◽  
Vaccine Effectiveness ◽  
Short Term ◽  
Correlates Of Protection ◽  
The United Kingdom ◽  
Herd Immunity Effect ◽  
Bactericidal Antibody ◽  
Low Levels

ABSTRACT Meningococcal serogroup C conjugate (MCC) vaccines were licensed in the United Kingdom more than 10 years ago based on correlates of protection that had previously been established for serogroup C-containing polysaccharide vaccines by using the serum bactericidal antibody (SBA) assay. These correlates of protection were subsequently validated against postlicensure estimates of observed vaccine effectiveness up to 7 to 9 months after the administration of the MCC vaccine. Vaccine effectiveness was, however, shown to fall significantly more than 1 year after the administration of a 3-dose course in infancy. Despite this finding, the marked impact on serogroup C disease has been sustained, with the lowest recorded incidence (0.02 case per 100,000 population) in the 2008-2009 epidemiological year, mainly due to the indirect herd immunity effect of the vaccine in reducing carriage. Updated estimates of vaccine effectiveness through 30 June 2009 confirmed high short-term protection after vaccination in infancy, at 97% (95% confidence interval [CI], 91% to 99%), falling to 68% (95% CI, −63% to 90%) more than a year after vaccination. The observed vaccine effectiveness more than 12 months postvaccination was consistent with measured declining SBA levels, but confidence intervals were imprecise; vaccine effectiveness estimates were consistent with SBA titers of 1:4 or 1:8 as correlates of long-term protection after a primary course in infants. Modeling suggested that protection against carriage persists for at least 3 years and predicted the stabilization of serogroup C disease at low levels (fewer than 50 cases per year) up to 2015-2016.

scholarly journals Impact of Meningococcal Serogroup C Conjugate Vaccines on Carriage and Herd Immunity

2008 ◽  
Vol 197 (5) ◽  
pp. 737-743 ◽  
Author(s):  
Martin C J Maiden ◽  
Ana Belén Ibarz-Pavón ◽  
Rachel Urwin ◽  
Stephen J Gray ◽  
Nicholas J Andrews ◽  
...  
Keyword(s):  
Vaccine Efficacy ◽  
Rate Ratio ◽  
Herd Immunity ◽  
Age Groups ◽  
Carriage Rate ◽  
Vaccine Introduction ◽  
The United Kingdom ◽  
Asymptomatic Carriage ◽  
The Impact

AbstractBackground. In 1999, meningococcal serogroup C conjugate (MCC) vaccines were introduced in the United Kingdom for those under 19 years of age. The impact of this intervention on asymptomatic carriage of meningococci was investigated to establish whether serogroup replacement or protection by herd immunity occurred.Methods. Multicenter surveys of carriage were conducted during vaccine introduction and on 2 successive years, resulting in a total of 48,309 samples, from which 8599 meningococci were isolated and characterized by genotyping and phenotyping.Results. A reduction in serogroup C carriage (rate ratio, 0.19) was observed that lasted at least 2 years with no evidence of serogroup replacement. Vaccine efficacy against carriage was 75%, and vaccination had a disproportionate impact on the carriage of sequence type (ST)-11 complex serogroup C meningococci that (rate ratio, 0.06); these meningococci also exhibited high rates of capsule expression.Conclusions. The impact of vaccination with MCC vaccine on the prevalence of carriage of group C meningococci was consistent with herd immunity. The high impact on the carriage of ST-11 complex serogroup C could be attributed to high levels of capsule expression. High vaccine efficacy against disease in young children, who were not protected long-term by the schedule initially used, is attributed to the high vaccine efficacy against carriage in older age groups.

Calibrating an SIR model for South Korea COVID-19 infections and predicting vaccination impact (Preprint)

2021 ◽  
Author(s):  
Brandon Pae
Keyword(s):  
South Korea ◽  
Vaccination Coverage ◽  
Herd Immunity ◽  
Sir Model ◽  
Transmission Dynamics ◽  
Effective Vaccine ◽  
Epidemiological Models ◽  
Policy Decisions

UNSTRUCTURED In the span of 1.5 years, COVID-19 has caused more than 4 million deaths worldwide. To prevent such a catastrophe from reoccurring, it is necessary to test and refine current epidemiological models that impact policy decisions. Thus, we developed a deterministic SIR model to examine the long-term transmission dynamics of COVID-19 in South Korea. Using this model, we analyzed how vaccines would affect the number of cases. We found that a 70% vaccination coverage with a 100% effective vaccine would effectively eliminate the number of cases and herd immunity would have been obtained approximately 85 days after February 15 had there not been a reintroduction of cases.

scholarly journals British librarianship in the time of Covid-19

2021 ◽  
pp. 095574902198958
Author(s):  
Nick Poole
Keyword(s):  
Chief Executive ◽  
Effective Vaccine ◽  
Health Crisis ◽  
Face To Face ◽  
Public Health Crisis ◽  
The United Kingdom ◽  
Look Ahead ◽  
Challenges And Opportunities ◽  
Information Professionals

Covid-19 has impacted on every aspect of daily life across the United Kingdom. At once both a public health crisis and an ‘infodemic’ of misinformation, it has presented unique challenges for library and information services. Yet despite these challenges, the pandemic has also given our services a new-found relevance. Readership has increased dramatically. Librarians in health have turned their skills to the search for an effective vaccine. Our colleagues in schools, colleges and Universities have stepped up to help their institutions achieve a rapid ‘digital pivot’. In the private sector, librarians and information professionals have used their skills to help their companies go online and to ensure the continuity of their activities. It is not yet clear how the pandemic will change our habits, attitudes and behaviours in the long term. As we begin to look ahead to a future in which ‘digital’ has taken its place on equal terms with face-to-face services, the library and information sector is uniquely positioned to help our communities thrive in a post-pandemic era. In this article, Nick Poole, the Chief Executive of CILIP, the United Kingdom’s Library and Information Association, looks back at the last year for UK libraries and explores the challenges and opportunities ahead.

scholarly journals How vaccination and contact isolation might interact to suppress transmission of Covid-19: a DCM study

2021 ◽  
Author(s):  
Karl J. Friston ◽  
Anthony Costello ◽  
Guillaume Flandin ◽  
Adeel Razi
Keyword(s):  
Causal Model ◽  
Herd Immunity ◽  
Contact Tracing ◽  
Effective Vaccine ◽  
Full Potential ◽  
Contact Rates ◽  
The United Kingdom ◽  
Contact Isolation ◽  
Community Transmission ◽  
Dynamic Causal Model

AbstractThis report describes a dynamic causal model that could be used to address questions about the rollout and efficacy of vaccines in the United Kingdom. For example, is suppression of community transmission a realistic aspiration? And, if not, what kind of endemic equilibrium might be achieved? What percentage of the population needs to be vaccinated? And over what timescale? It focuses on the synergies among (i) vaccination, (ii) the supported isolation of contacts of confirmed cases and (iii) restrictions on contact rates (i.e., lockdown and social distancing). To model these mitigations, we used a dynamic causal model that embeds an epidemiological model into agent-based behavioural model. The model structure and parameters were optimised to best explain responses—to the first and subsequent waves—enabling predictions over the forthcoming year under counterfactual scenarios. Illustrative analyses suggest that the full potential of vaccination is realised by increasing the efficacy of contact tracing: for example, under idealised (best case) assumptions—of an effective vaccine and efficient isolation of infected pre-symptomatic cases— suppression of community transmission would require 50% herd immunity by vaccinating 22% by the end of 2021; i.e., 15 million people or about 50,000 per day. With no change in the isolation of contacts, 36% would require vaccination, i.e., 25 million people. These figures should not be read as estimates of the actual number of people requiring vaccination; however, they illustrate the potential of this kind of model to quantify interactions among public health interventions. We anticipate using this model in a few months—to estimate the average effectiveness of vaccines when more data become available.

Demographic gaps between Syrian and the European populations: What do they suggest?

2017 ◽  
Vol 7 (2) ◽  
pp. 207-230 ◽  
Author(s):  
Mustafa Murat Yucesahin ◽  
Ibrahim Sirkeci
Keyword(s):  
Transition Theory ◽  
World Population ◽  
Demographic Analysis ◽  
Demographic Differences ◽  
Syrian Crisis ◽  
The United Kingdom ◽  
Syrian Population ◽  
Displaced People ◽  
Near Future

Syrian crisis resulted in at least 6.1 million externally displaced people 983,876 of whom are in Europe while the rest are in neighbouring countries in the region. Turkey, due to its geographical proximity and substantial land borders with the country, has been the most popular destination for those fleeing Syria since April 2011. Especially after 2012, a sharp increase in the number of Syrian refugees arriving in Turkey was witnessed. This has triggered an exponential growth in academic and public interest in Syrian population. Numerous reports mostly based on non-representative sample surveys have been disseminated whilst authoritative robust analyses remained absent. This study aims to fill this gap by offering a comprehensive demographic analysis of the Syrian population. We focus on the demographic differences (from 1950s to 2015) and demographic trends (from 2015 to 2100) in medium to long term, based on data from World Population Prospects (WPP). We offer a comparative picture to underline potential changes and convergences between populations in Syria, Turkey, Germany, and the United Kingdom. We frame our discussion here with reference to the demographic transition theory to help understanding the implications for movers and non-movers in receiving countries in the near future.

SARS-CoV-2 Biology Insights, Part IV.Antibody-Dependent Enhancement (ADE) and the tricky “Herd Immunity”: narrative review (Preprint)

2020 ◽  
Author(s):  
Laura Lafon-Hughes
Keyword(s):  
Viral Infection ◽  
Viral Entry ◽  
Neutralizing Antibodies ◽  
Vaccine Development ◽  
Whooping Cough ◽  
Common Knowledge ◽  
Herd Immunity ◽  
Life Quality ◽  
Host Cells ◽  
System P

BACKGROUND It is common knowledge that vaccination has improved our life quality and expectancy since it succeeded in achieving almost eradication of several diseases including chickenpox (varicella), diphtheria, hepatitis A and B, measles, meningococcal, mumps, pneumococcal, polio, rotavirus, rubella, tetanus and whooping cough (pertussis) Vaccination success is based on vaccine induction of neutralizing antibodies that help fight the infection (e.g. by a virus), preventing the disease. Conversely, Antibody-dependent enhancement (ADE) of a viral infection occurs when anti-viral antibodies facilitate viral entry into host cells and enhance viral infection in these cells. ADE has been previously studied in Dengue and HIV viruses and explains why a second infection with Dengue can be lethal. As already reviewed in Part I and Part II, SARS-Cov-2 shares with HIV not only 4 sequences in the Spike protein but also the capacity to attack the immune system. OBJECTIVE As HIV presents ADE, we wondered whether this was also the case regarding SARS-CoV-2. METHODS A literature review was done through Google. RESULTS SARS-CoV-2 presents ADE. As SARS, which does not have the 4 HIV-like inserts, has the same property, ADE would not be driven by the HIV-like spike sequences. CONCLUSIONS ADE can explain the failure of herd immunity-based strategies and will also probably hamper anti-SARS-CoV-2 vaccine development. As reviewed in Part I, there fortunately are promising therapeutic strategies for COVID-19, which should be further developed. In the meantime, complementary countermeasures to protect mainly the youth from this infection are presented to be discussed in Part V Viewpoint.

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