Covid-19: how to prioritize worse-off populations in allocating safe and effective vaccines

Spatial Accessibility and Uptake of Pediatric COVID-19 Vaccinations by Social Vulnerability

BACKGROUND AND OBJECTIVES

Geographic accessibility predicts pediatric preventive care utilization, including vaccine uptake. However, spatial inequities in the pediatric coronavirus disease 2019 (COVID-19) vaccination rollout remain underexplored. We assessed the spatial accessibility of vaccination sites and analyzed predictors of vaccine uptake.

METHODS

In this cross-sectional study of pediatric COVID-19 vaccinations from the US Vaccine Tracking System as of July 29, 2022, we described spatial accessibility by geocoding vaccination sites, measuring travel times from each Census tract population center to the nearest site, and weighting tracts by their population demographics to obtain nationally representative estimates. We used quasi-Poisson regressions to calculate incidence rate ratios, comparing vaccine uptake between counties with highest and lowest quartile Social Vulnerability Index scores: socioeconomic status (SES), household composition and disability (HCD), minority status and language (MSL), and housing type and transportation.

RESULTS

We analyzed 15 233 956 doses administered across 27 526 sites. Rural, uninsured, white, and Native American populations experienced longer travel times to the nearest site than urban, insured, Hispanic, Black, and Asian American populations. Overall Social Vulnerability Index, SES, and HCD were associated with decreased vaccine uptake among children aged 6 months to 4 years (overall: incidence rate ratio 0.70 [95% confidence interval 0.60-0.81]; SES: 0.66 [0.58-0.75]; HCD: 0.38 [0.33-0.44]) and 5 years to 11 years (overall: 0.85 [0.77-0.95]; SES: 0.71 [0.65-0.78]; HCD: 0.67 [0.61-0.74]), whereas social vulnerability by MSL was associated with increased uptake (6 months-4 years: 5.16 [3.59-7.42]; 5 years-11 years: 1.73 [1.44-2.08]).

CONCLUSIONS

Pediatric COVID-19 vaccine uptake and accessibility differed by race, rurality, and social vulnerability. National supply data, spatial accessibility measurement, and place-based vulnerability indices can be applied throughout public health resource allocation, surveillance, and research.

Modeling the COVID-19 pandemic: a primer and overview of mathematical epidemiology

Since the start of the still ongoing COVID-19 pandemic, there have been many modeling efforts to assess several issues of importance to public health. In this work, we review the theory behind some important mathematical models that have been used to answer questions raised by the development of the pandemic. We start revisiting the basic properties of simple Kermack-McKendrick type models. Then, we discuss extensions of such models and important epidemiological quantities applied to investigate the role of heterogeneity in disease transmission e.g. mixing functions and superspreading events, the impact of non-pharmaceutical interventions in the control of the pandemic, vaccine deployment, herd-immunity, viral evolution and the possibility of vaccine escape. From the perspective of mathematical epidemiology, we highlight the important properties, findings, and, of course, deficiencies, that all these models have.

Representation of Ethics in COVID-19 Research: A Systematic Review

Background:

Ethical discourse in the scientific community facilitates the humane conduct of research. The urgent response to COVID-19 has rapidly generated a large body of literature to help policymakers and physicians address novel pandemic challenges. Plastic surgeons, in particular, have to manage the postponement of elective procedures and safely provide care for non–COVID-19 patients. Although COVID-19 research may provide guidance on these challenges, the extent to which ethical discussions are present in these publications remains unknown.

Methods:

Articles were identified systematically by searching the PubMed, Embase, Central, and Scopus databases using search terms related to ethics and COVID-19. The search included articles published during the first 9 months of the COVID-19 pandemic. The following data were extracted: presence of an ethical discussion, date of publication, topic of ethical discussion, and scientific discipline of the article.

Results:

One thousand seven hundred fifty-three articles were included, of which seven were related to plastic surgery. The ethical principle with the greatest representation was nonmaleficence, whereas autonomy had the least representation. Equity and access to care was the most common topic of ethical discussion; the mental health effects of COVID-19 were the least common. The principle of justice had the greatest variation in representation.

Conclusions:

In a systematic review of COVID-19–related articles that were published during the first 9 months of the pandemic, the ethical principles of autonomy and justice are neglected in ethical discussions. As ethical dilemmas related to COVID-19 remain prevalent in plastic surgery, attention to ethical discourse should remain a top priority for leaders in the field.

Non-pharmaceutical interventions and COVID-19 vaccination strategies in Senegal: a modelling study

Background

When vaccines against the novel COVID-19 were available in Senegal, many questions were raised. How long should non-pharmaceutical interventions (NPIs) be maintained during vaccination roll-out? What are the best vaccination strategies?

Methods

In this study, we used an age-structured dynamic mathematical model. This model uses parameters based on SARS-CoV-2 virus, information on different types of NPIs, epidemiological and demographic data, some parameters relating to hospitalisations and vaccination in Senegal.

Results

In all scenarios explored, the model predicts a larger third epidemic wave of COVID-19 in terms of new cases and deaths than the previous waves. In a context of limited vaccine supply, vaccination alone will not be sufficient to control the epidemic, and the continuation of NPIs is necessary to flatten the epidemic curve. Assuming 20% of the population have been vaccinated, the optimal period to relax NPIs would be a few days from the last peak. Regarding the prioritisation of age groups to be vaccinated, the model shows that it is better to vaccinate individuals aged 5–60 years and not just the elderly (over 60 years) and those in high-risk groups. This strategy could be more cost-effective for the government, as it would reduce the high costs associated with hospitalisation. In terms of vaccine distribution, the optimal strategy would be to allocate full dose to the elderly. If vaccine doses are limited, half dose followed by full dose would be sufficient for people under 40 years because whether they receive half or full dose, the reduction in hospitalisations would be similar and their death-to-case ratio is very low.

Conclusions

This study could be presented as a decision support tool to help devise strategies to control the COVID-19 pandemic and help the Ministry of Health to better manage and allocate the available vaccine doses.

Not the great equalizers: Covid-19, 1918-20 influenza, and the need for a paradigm shift in pandemic preparedness

Despite common perceptions to the contrary, pandemic diseases do not affect populations indiscriminately. In this paper, we review literature produced by demographers, historians, epidemiologists, and other researchers on disparities during the 1918-20 influenza pandemic and the Covid-19 pandemic. Evidence from these studies demonstrates that lower socio-economic status and minority/stigmatized race or ethnicity are associated with higher morbidity and mortality. However, such research often lacks theoretical frameworks or appropriate data to explain the mechanisms underlying these disparities fully. We suggest using a framework that considers proximal and distal factors contributing to differential exposure, susceptibility, and consequences as one way to move this research forward. Further, current pandemic preparedness plans emphasize medically defined risk groups and epidemiological approaches. Therefore, we conclude by arguing in favour of a transdisciplinary paradigm that recognizes socially defined risk groups, includes input from the social sciences and humanities and other diverse perspectives, and contributes to the reduction of health disparities before a pandemic hits.

Rationing and Disparities in Health Care: Implications for Radiology Clinical Practice Guidelines

We examine the relationship between the rationing of health care resources and disparities in health care delivery and the specific implications for radiologic resource allocation frameworks such as the ACR Appropriateness Criteria. We explore what rationing is in this context and how it is manifested in radiology. We review how rationing has taken many forms and how rationing has influenced the development of disparities in access and outcomes within health care and specifically within the context of radiology. We describe how the relationship between rationing and health care delivery disparities manifested during the coronavirus disease 2019 pandemic and the corrective measures that were proposed to established rationing frameworks to facilitate more equitable pandemic-related resource distribution. We offer suggestions regarding how such solutions might be brought into radiologic resource allocation schemes to help mitigate disparities in radiologic care in the future.

The association between socioeconomic status and pandemic influenza: Systematic review and meta-analysis

BACKGROUND

The objective of this study is to document whether and to what extent there is an association between socioeconomic status (SES) and disease outcomes in the last five influenza pandemics.

METHODS/PRINCIPLE FINDINGS

The review included studies published in English, Danish, Norwegian and Swedish. Records were identified through systematic literature searches in six databases. We summarized results narratively and through meta-analytic strategies. Only studies for the 1918 and 2009 pandemics were identified. Of 14 studies on the 2009 pandemic including data on both medical and social risk factors, after controlling for medical risk factors 8 demonstrated independent impact of SES. In the random effect analysis of 46 estimates from 35 studies we found a pooled mean odds ratio of 1.4 (95% CI: 1.2-1.7, p < 0.001), comparing the lowest to the highest SES, but with substantial effect heterogeneity across studies,-reflecting differences in outcome measures and definitions of case and control samples. Analyses by pandemic period (1918 or 2009) and by level of SES measure (individual or ecological) indicated no differences along these dimensions. Studies using healthy controls tended to document that low SES was associated with worse influenza outcome, and studies using infected controls find low SES associated with more severe outcomes. A few studies compared severe outcomes (ICU or death) to hospital admissions but these did not find significant SES associations in any direction. Studies with more unusual comparisons (e.g., pandemic vs seasonal influenza, seasonal influenza vs other patient groups) reported no or negative non-significant associations.

CONCLUSIONS/SIGNIFICANCE

We found that SES was significantly associated with pandemic influenza outcomes with people of lower SES having the highest disease burden in both 1918 and 2009. To prepare for future pandemics, we must consider social vulnerability. The protocol for this study has been registered in PROSPERO (ref. no 87922) and has been published Mamelund et al. (2019).

Equitable allocation of COVID-19 vaccines in the United States

Many vaccine rationing guidelines urge planners to recognize, and ideally reduce, inequities. In the United States, allocation frameworks are determined by each of the Centers for Disease Control and Prevention's 64 jurisdictions (50 states, the District of Columbia, five cities and eight territories). In this study, we analyzed vaccine allocation plans published by 8 November 2020, tracking updates through to 30 March 2021. We evaluated whether jurisdictions adopted proposals to reduce inequity using disadvantage indices and related place-based measures. By 30 March 2021, 14 jurisdictions had prioritized specific zip codes in combination with metrics such as COVID-19 incidence, and 37 jurisdictions (including 34 states) had adopted disadvantage indices, compared to 19 jurisdictions in November 2020. Uptake of indices doubled from 7 to 14 among the jurisdictions with the largest shares of disadvantaged communities. Five applications were distinguished: (1) prioritizing disadvantaged groups through increased shares of vaccines or vaccination appointments; (2) defining priority groups or areas; (3) tailoring outreach and communication; (4) planning the location of dispensing sites; and (5) monitoring receipt. To ensure that equity features centrally in allocation plans, policymakers at the federal, state and local levels should universalize the uptake of disadvantage indices and related place-based measures.

Maximization of Open Hospital Capacity under Shortage of SARS-CoV-2 Vaccines-An Open Access, Stochastic Simulation Tool

Motive. The Covid-19 pandemic has led to the novel situation that hospitals must prioritize staff for a vaccine rollout while there is acute shortage of the vaccine. In spite of the availability of guidelines from state agencies, there is partial confusion about what an optimal rollout plan is. This study investigates effects in a hospital model under different rollout schemes. Methods. A simulation model is implemented in VBA, and is studied for parameter variation in a predefined hospital setting. The implemented code is available as open access supplement. Main results. A rollout scheme assigning vaccine doses to staff primarily by staff's pathogen exposure maximizes the predicted open hospital capacity when compared to a rollout based on a purely hierarchical prioritization. The effect increases under resource scarcity and greater disease activity. Nursing staff benefits most from an exposure focused rollout. Conclusions. The model employs SARS-CoV-2 parameters; nonetheless, effects observable in the model are transferable to other infectious diseases. Necessary future prioritization plans need to consider pathogen characteristics and social factors.

COVID-19 Pandemic and Equal Access to Vaccines

The COVID-19 pandemic has evidenced the chronic inequality that exists between populations and communities as regards global healthcare. Vaccination, an appropriate tool for the prevention of infection, should be guaranteed by means of proportionate interventions to defeat such inequality in populations and communities affected by a higher risk of infection. Equitable criteria of justice should be identified and applied with respect to access to vaccination and to the order in which it should be administered. This article analyzes, as regards the worldwide distribution of anti-COVID-19 vaccines, the various ways the principle of equity has been construed and applied or even overlooked. The main obstacle to equal access to vaccines is vaccine nationalism. The perception of equity varies with the differing reference values adopted. Adequate response to needs appears to be the principal rule for achieving the criterion of equity in line with distributive justice. Priorities must be set equitably based on rational parameters in accordance with current needs. The entire process must be governed by transparency, from parameter identification to implementation. The issue of equal access to vaccination affects the entire world population, necessitating specific protective interventions. In light of this, the World Health Organization (WHO) has devised the COVAX plan to ensure that even the poorest nations of the world receive the vaccine; certain initiatives are also supported by the European Union (EU). This pandemic has brought to the fore the need to build a culture of equitable relationships both in each country’s own domain and with the rest of the world.

Modelling of COVID-19 vaccination strategies and herd immunity, in scenarios of limited and full vaccine supply in NSW, Australia

Several vaccines for SARS-CoV-2 are expected to be available in Australia in 2021. Initial supply is limited and will require a judicious vaccination strategy until supply is unrestricted. If vaccines have efficacy as post-exposure prophylaxis (PEP) in contacts, this provides more policy options. We used a deterministic mathematical model of epidemic response with limited supply (age-targeted or ring vaccination) and mass vaccination for the State of New South Wales (NSW) in Australia. For targeted vaccination, the effectiveness of vaccinating health workers, young people and older adults was compared. For mass vaccination, we tested varying vaccine efficacy (VE) and distribution capacities. With a limited vaccine stockpile enough for 1 million people in NSW, if there is efficacy as PEP, the most efficient way to control COVID-19 will be ring vaccination, however at least 90% of contacts per case needs to be traced and vaccinated. Health worker vaccination is required for health system resilience. Age based strategies with restricted doses make minimal impact on the epidemic, but vaccinating older people prevents more deaths. Herd immunity can only be achieved with mass vaccination. With 90% VE against all infection, herd immunity can be achieved by vaccinating 66% of the population. A vaccine with less than 70% VE cannot achieve herd immunity and will result in ongoing risk of outbreaks. For mass vaccination, distributing at least 60,000 doses per day is required to achieve control. Slower rates of vaccination will result in the population living with COVID-19 longer, and higher cases and deaths.

Ethics of vaccination: Should capability measures be used to inform SARS-CoV-2 vaccination strategies?

Proposals for SARS-CoV-2 virus vaccination priorities in the UK and in many other countries are heavily influenced by epidemiological models, which use outcome measures such as deaths or hospitalisation. Limiting the values under consideration to those attributable to the direct effects of infection has the advantage of simplifying the models and the process of decision-making. However, the consequences of the pandemic extend beyond outcomes directly attributable to SARS-CoV-2 infection, and include restrictions on educational and work opportunities, access to services, recreational activities, affiliations and relationships with others, freedom of movement (including escaping abusive relationships), and other determinants of human experience. Capability theory gives emphasis to the freedoms that individuals have to express themselves (in doings and beings). Restrictions on freedoms restrict our capabilities. Capability theory has been used to provide a framework for the evaluation and comparison of international development approaches and in the evaluation of public health policy. There is a clustering of disadvantages associated with this pandemic that adds to pre-existing inequalities. Much of the disadvantage engendered in the SARS-CoV-2 pandemic is left out when public health policy is based on a limited range of metrics. Acknowledging the impact of policy across the range of human freedoms at both a national and international level has the potential to improve policy, facilitate the mitigation of direct and indirect adverse consequences, and improve public confidence and the effectiveness of vaccine deployment strategies.