A collective risk dilemma for tourism restrictions under the COVID-19 context.

The current COVID-19 pandemic has impacted millions of people and the global economy. Tourism has been one the most affected economic sectors because of the mobility restrictions established by governments and uncoordinated actions from origin and destination regions. The coordination of restrictions and reopening policies could help control the spread of virus and enhance economies, but this is not an easy endeavor since touristic companies, citizens, and local governments have conflicting interests. We propose an evolutionary game model that reflects a collective risk dilemma behind these decisions. To this aim, we represent regions as players, organized in groups; and consider the perceived risk as a strict lock-down and null economic activity. The costs for regions when restricting their mobility are heterogeneous, given that the dependence on tourism of each region is diverse. Our analysis shows that, for both large populations and the EU NUTS2 case study, the existence of heterogeneous costs enhances global agreements. Furthermore, the decision on how to group regions to maximize the regions' agreement of the population is a relevant issue for decision makers to consider. We find out that a layout of groups based on similar costs of cooperation boosts the regions' agreements and avoid the risk of having a total lock-down and a negligible tourism activity. These findings can guide policy makers to facilitate agreements among regions to maximize the tourism recovery.

The development of nations conditions the disease space.

Using the economic complexity methodology on data for disease prevalence in 195 countries during the period of 1990-2016, we propose two new metrics for quantifying the disease space of countries. With these metrics, we analyze the geography of diseases and empirically investigate the effect of economic development on the health complexity of countries. We show that a higher income per capita increases the complexity of countries' diseases. We also show that complex diseases tend to be non-ubiquitous diseases that are prevalent in disease-diversified (complex) countries, while non-complex diseases tend to be non-ubiquitous diseases that are prevalent in non-diversified (non-complex) countries. Furthermore, we build a disease-level index that links a disease to the average level of GDP per capita of the countries in which the disease is prevalent. With this index, we highlight the link between economic development and the complexity of diseases and illustrate how increases in income per capita are associated with more complex diseases.

Seasonal influenza vaccination in Kenya: an economic evaluation using dynamic transmission modelling.

BACKGROUND: There is substantial burden of seasonal influenza in Kenya, which led the government to consider introducing a national influenza vaccination programme. Given the cost implications of a nationwide programme, local economic evaluation data are needed to inform policy on the design and benefits of influenza vaccination. We set out to estimate the cost-effectiveness of seasonal influenza vaccination in Kenya. METHODS: We fitted an age-stratified dynamic transmission model to active surveillance data from patients with influenza from 2010 to 2018. Using a societal perspective, we developed a decision tree cost-effectiveness model and estimated the incremental cost-effectiveness ratio (ICER) per disability-adjusted life year (DALY) averted for three vaccine target groups: children 6-23 months (strategy I), 2-5 years (strategy II) and 6-14 years (strategy III) with either the Southern Hemisphere influenza vaccine (Strategy A) or Northern Hemisphere vaccine (Strategy B) or both (Strategy C: twice yearly vaccination campaigns, or Strategy D: year-round vaccination campaigns). We assessed cost-effectiveness by calculating incremental net monetary benefits (INMB) using a willingness-to-pay (WTP) threshold of 1-51% of the annual gross domestic product per capita ($17-$872). RESULTS: The mean number of infections across all ages was 2-15 million per year. When vaccination was well timed to influenza activity, the annual mean ICER per DALY averted for vaccinating children 6-23 months ranged between $749 and $1385 for strategy IA, $442 and $1877 for strategy IB, $678 and $4106 for strategy IC and $1147 and $7933 for strategy ID. For children 2-5 years, it ranged between $945 and $1573 for strategy IIA, $563 and $1869 for strategy IIB, $662 and $4085 for strategy IIC, and $1169 and $7897 for strategy IID. For children 6-14 years, it ranged between $923 and $3116 for strategy IIIA, $1005 and $2223 for strategy IIIB, $883 and $4727 for strategy IIIC and $1467 and $6813 for strategy IIID. Overall, no vaccination strategy was cost-effective at the minimum ($17) and median ($445) WTP thresholds. Vaccinating children 6-23 months once a year had the highest mean INMB value at $872 (WTP threshold upper limit); however, this strategy had very low probability of the highest net benefit. CONCLUSION: Vaccinating children 6-23 months once a year was the most favourable vaccination option; however, the strategy is unlikely to be cost-effective given the current WTP thresholds.

Advocating an attack against severe malaria: a cost-effectiveness analysis.

BACKGROUND: A recent study found that the gut microbiota, Lactobacillus and Bifidobacterium, have the ability to modulate the severity of malaria. The modulation of the severity of malaria is not however, the typical focal point of most widespread interventions. Thus, an essential element of information required before serious consideration of any intervention that targets reducing severe malaria incidence is a prediction of the health benefits and costs required to be cost-effective. METHODS: Here, we developed a mathematical model of malaria transmission to evaluate an intervention that targets reducing severe malaria incidence. We consider intervention scenarios of a 2-, 7-, and 14-fold reduction in severe malaria incidence, based on the potential reduction in severe malaria incidence caused by gut microbiota, under entomological inoculation rates occurring in 41 countries in sub-Saharan Africa. For each intervention scenario, disability-adjusted life years averted and incremental cost-effectiveness ratios were estimated using country specific data, including the reported proportions of severe malaria incidence in healthcare settings. RESULTS: Our results show that an intervention that targets reducing severe malaria incidence with annual costs between $23.65 to $30.26 USD per person and causes a 14-fold reduction in severe malaria incidence would be cost-effective in 15-19 countries and very cost-effective in 9-14 countries respectively. Furthermore, if model predictions are based on the distribution of gut microbiota through a freeze-dried yogurt that cost $0.20 per serving, a 2- to 14-fold reduction in severe malaria incidence would be cost-effective in 29 countries and very cost-effective in 25 countries. CONCLUSION: Our findings indicate interventions that target severe malaria can be cost-effective, in conjunction with standard interventions, for reducing the health burden and costs attributed to malaria. While our results illustrate a stronger cost-effectiveness for greater reductions, they consistently show that even a limited reduction in severe malaria provides substantial health benefits, and could be economically viable. Therefore, we suggest that interventions that target severe malaria are worthy of consideration, and merit further empirical and clinical investigation.

Cost-effectiveness of increased HIV testing among MSM in The Netherlands.

OBJECTIVES: To assess the cost-effectiveness of increased consistent HIV testing among MSM in the Netherlands. METHODS: Among MSM testing at sexually transmitted infection clinics in the Netherlands in 2014-2015, approximately 20% tested consistently every 6 months. We examined four scenarios with increased percentage of MSM testing every 6 months: a small and a moderate increase among all MSM; a small and a moderate increase only among MSM with at least 10 partners in the preceding 6 months. We used an agent-based model to calculate numbers of HIV infections and AIDS cases prevented with increased HIV testing. These numbers were used in an economic model to calculate costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs) due to increased testing, over 2018-2027, taking a healthcare payer perspective. RESULTS: A small increase in the percentage testing every 6 months among all MSM resulted in 490 averted HIV infections and an average ICER of &OV0556;27 900/QALY gained. A moderate increase among all MSM, resulted in 1380 averted HIV infections and an average ICER of &OV0556;36 700/QALY gained. Both were not cost-effective, with a &OV0556;20 000 willingness-to-pay threshold. Increasing the percentage testing every 6 months only among MSM with at least 10 partners in the preceding 6 months resulted in less averted HIV infections than increased testing among all MSM, but was on average cost-saving. CONCLUSION: Increased HIV testing can prevent considerable numbers of new HIV infections among MSM, but may be cost-effective only if targeted at high-risk individuals, such as those with many partners.

The impact of transmission dynamics of rabies control: Systematic review.

The public health and economic burden of rabies has led to major intersectoral initiatives worldwide to reduce its burden. Over the last decade, the impact of rabies prevention and control programmes in real-world settings has become increasingly evident, especially in countries where most rabies exposures and deaths occur, but they have yet to successfully eradicate rabies due to limited access to health care services. We aimed to systematically review published transmission dynamic modelling studies of rabies in both humans and dogs with a focus on studies which estimated the epidemiological and economic impact of different preventive measures. The findings are intended to inform the World Health Organization's (WHO) Strategic Advisory Group of Experts on Immunization (SAGE) to improve programmatic feasibility and clinical practice in rabies. Medline and Scopus were systematically searched for peer-reviewed articles which were published up to 14th June 2017. In addition, studies identified from a meeting of the WHO Expert Consultation on Rabies on 26-28th April 2017 in Bangkok, Thailand were added, resulting in 19 articles which were included in the review. Results from the disease modelling indicated that the basic reproduction number was low (less than 2 in all but one study). All studies found that rabies control through canine vaccination was likely to be effective in terms of reducing the incidence of rabies in dogs and/or humans, with most studies suggesting 70% annual coverage was adequate. Vaccine coverage, dog density and birth rate were identified as crucial factors influencing the effectiveness of the interventions. In conclusion, the findings from this review suggest that rabies control through canine vaccination is likely to be effective in reducing the incidence of rabies. Vaccine coverage, dog density and canine birth rate were identified as critical factors influencing the effectiveness of vaccination interventions.

Quantifying the impact of social groups and vaccination on inequalities in infectious diseases using a mathematical model.

BACKGROUND: Social and cultural disparities in infectious disease burden are caused by systematic differences between communities. Some differences have a direct and proportional impact on disease burden, such as health-seeking behaviour and severity of infection. Other differences-such as contact rates and susceptibility-affect the risk of transmission, where the impact on disease burden is indirect and remains unclear. Furthermore, the concomitant impact of vaccination on such inequalities is not well understood. METHODS: To quantify the role of differences in transmission on inequalities and the subsequent impact of vaccination, we developed a novel mathematical framework that integrates a mechanistic model of disease transmission with a demographic model of social structure, calibrated to epidemiologic and empirical social contact data. RESULTS: Our model suggests realistic differences in two key factors contributing to the rates of transmission-contact rate and susceptibility-between two social groups can lead to twice the risk of infection in the high-risk population group relative to the low-risk population group. The more isolated the high-risk group, the greater this disease inequality. Vaccination amplified this inequality further: equal vaccine uptake across the two population groups led to up to seven times the risk of infection in the high-risk group. To mitigate these inequalities, the high-risk population group would require disproportionately high vaccination uptake. CONCLUSION: Our results suggest that differences in contact rate and susceptibility can play an important role in explaining observed inequalities in infectious diseases. Importantly, we demonstrate that, contrary to social policy intentions, promoting an equal vaccine uptake across population groups may magnify inequalities in infectious disease risk.

Sustainable access to deworming drugs in a changing landscape.

The global effort to control and eliminate soil-transmitted helminthiasis (STH) currently depends on donations of albendazole and mebendazole, which reached more than 530 million children in 2016. As we approach 2020, the WHO goal of eliminating STH as a public health problem will not be met in most endemic countries, and ongoing treatment will be necessary. Additionally, the volume of drugs required might increase because global strategies for STH aim to interrupt transmission. Under the 2012 London Declaration on Neglected Tropical Diseases, pharmaceutical company commitments to donate drugs to control or eliminate neglected tropical diseases extend to 2020. We are approaching a period of uncertainty regarding different strategies for control and elimination of STH, the size and target populations for future donations, and optimum drugs and drug combinations. Long-term reliance on large-scale donation of deworming drugs is not sustainable. The global STH community need to develop a strategy to secure a sustainable global supply of affordable and effective anthelmintic drugs. This strategy should include improvement of the quality of generic drugs through innovative technical partnerships.

Cost-effectiveness of interventions to improve hand hygiene in healthcare workers in middle-income hospital settings: a model-based analysis.

BACKGROUND: Multi-modal interventions are effective in increasing hand hygiene (HH) compliance among healthcare workers, but it is not known whether such interventions are cost-effective outside high-income countries. AIM: To evaluate the cost-effectiveness of multi-modal hospital interventions to improve HH compliance in a middle-income country. METHODS: Using a conservative approach, a model was developed to determine whether reductions in meticillin-resistant Staphylococcus aureus bloodstream infections (MRSA-BSIs) alone would make HH interventions cost-effective in intensive care units (ICUs). Transmission dynamic and decision analytic models were combined to determine the expected impact of HH interventions on MRSA-BSI incidence and evaluate their cost-effectiveness. A series of sensitivity analyses and hypothetical scenarios making different assumptions about transmissibility were explored to generalize the findings. FINDINGS: Interventions increasing HH compliance from a 10% baseline to ≥20% are likely to be cost-effective solely through reduced MRSA-BSI. Increasing compliance from 10% to 40% was estimated to cost US$2515 per 10,000 bed-days with 3.8 quality-adjusted life-years (QALYs) gained in a paediatric ICU (PICU) and US$1743 per 10,000 bed-days with 3.7 QALYs gained in an adult ICU. If baseline compliance is not >20%, the intervention is always cost-effective even with only a 10% compliance improvement. CONCLUSION: Effective multi-modal HH interventions are likely to be cost-effective due to preventing MRSA-BSI alone in ICU settings in middle-income countries where baseline compliance is typically low. Where compliance is higher, the cost-effectiveness of interventions to improve it further will depend on the impact on hospital-acquired infections other than MRSA-BSI.

Cost-effectiveness of alternative strategies for provision of HIV preexposure prophylaxis for people who inject drugs.

BACKGROUND: Oral HIV preexposure prophylaxis (PrEP) has been recommended as a means of HIV prevention among people who inject drugs (PWIDs) but, at current prices, is unlikely to be cost-effective for all PWID. OBJECTIVE: To determine the cost-effectiveness of alternative strategies for enrolling PWID in PrEP. DESIGN: Dynamic network model that captures HIV transmission and progression among PWID in a representative US urban center. OUTCOME MEASURES: HIV infections averted, discounted costs and quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. INTERVENTION: We assume 25% PrEP coverage and investigate four strategies: first, random PWID are enrolled (Unselected Enrollment); second, individuals are randomly selected and enrolled together with their partners (Enroll Partners); third, individuals with the highest number of sexual and needle-sharing partnerships are enrolled (Most Partners); fourth, individuals with the greatest number of infected partners are enrolled (Most Positive Partners). RESULTS: PrEP can achieve significant health benefits: compared with the status quo of no PrEP, the strategies gain 1114 QALYs (Unselected Enrollment), 2194 QALYs (Enroll Partners), 2481 QALYs (Most Partners), and 3046 QALYs (Most Positive Partners) over 20 years in a population of approximately 8500 people. The incremental cost-effectiveness ratio of each strategy compared with the status quo (cost per QALY gained) is $272 000 (Unselected Enrollment), $158 000 (Enroll Partners), $124 000 (Most Partners), and $101 000 (Most Positive Partners). All strategies except Unselected Enrollment are cost-effective according to WHO criteria. CONCLUSION: Selection of high-risk PWID for PrEP can improve the cost-effectiveness of PrEP for PWID.

Lessons from a decade of individual-based models for infectious disease transmission: a systematic review (2006-2015).

BACKGROUND: Individual-based models (IBMs) are useful to simulate events subject to stochasticity and/or heterogeneity, and have become well established to model the potential (re)emergence of pathogens (e.g., pandemic influenza, bioterrorism). Individual heterogeneity at the host and pathogen level is increasingly documented to influence transmission of endemic diseases and it is well understood that the final stages of elimination strategies for vaccine-preventable childhood diseases (e.g., polio, measles) are subject to stochasticity. Even so it appears IBMs for both these phenomena are not well established. We review a decade of IBM publications aiming to obtain insights in their advantages, pitfalls and rationale for use and to make recommendations facilitating knowledge transfer within and across disciplines. METHODS: We systematically identified publications in Web of Science and PubMed from 2006-2015 based on title/abstract/keywords screening (and full-text if necessary) to retrieve topics, modeling purposes and general specifications. We extracted detailed modeling features from papers on established vaccine-preventable childhood diseases based on full-text screening. RESULTS: We identified 698 papers, which applied an IBM for infectious disease transmission, and listed these in a reference database, describing their general characteristics. The diversity of disease-topics and overall publication frequency have increased over time (38 to 115 annual publications from 2006 to 2015). The inclusion of intervention strategies (8 to 52) and economic consequences (1 to 20) are increasing, to the detriment of purely theoretical explorations. Unfortunately, terminology used to describe IBMs is inconsistent and ambiguous. We retrieved 24 studies on a vaccine-preventable childhood disease (covering 7 different diseases), with publication frequency increasing from the first such study published in 2008. IBMs have been useful to explore heterogeneous between- and within-host interactions, but combined applications are still sparse. The amount of missing information on model characteristics and study design is remarkable. CONCLUSIONS: IBMs are suited to combine heterogeneous within- and between-host interactions, which offers many opportunities, especially to analyze targeted interventions for endemic infections. We advocate the exchange of (open-source) platforms and stress the need for consistent "branding". Using (existing) conventions and reporting protocols would stimulate cross-fertilization between research groups and fields, and ultimately policy making in decades to come.

Estimated Coverage to Address Financial Barriers to HIV Preexposure Prophylaxis Among Persons With Indications for Its Use, United States, 2015.

BACKGROUND: An estimated 1.2 million American adults engage in sexual and drug use behaviors that place them at significant risk of acquiring HIV infection. Engagement in health care for the provision of daily oral antiretroviral medication as preexposure prophylaxis (PrEP), when clinically indicated, could substantially reduce the number of new HIV infections in these persons. However, resources to cover the financial cost of PrEP care are anticipated barriers for many of the populations with high numbers of new HIV infections. METHODS: Using nationally representative data, we estimated the current national met and unmet need for financial assistance with covering the cost of PrEP medication, clinical visits, and laboratory tests among adults with indications for its use, overall and by transmission risk population. RESULTS: This study found that of the 1.2 million adults estimated to have indications for PrEP use, <1% (∼7300) are in need of financial assistance for both PrEP medication and clinical care, at an estimated annual cost of $89 million. An additional 7% (∼86,300) are in need of financial assistance only for PrEP clinical care at an estimated annual cost of $119 million. CONCLUSIONS: This information on PrEP care costs, insurance coverage, and unmet financial need among persons in key HIV transmission risk subpopulations can inform policy makers at all levels as they consider how to address remaining financial barriers to the use of PrEP and accommodate any changes in eligibility for various insurance and financial assistance programs that may occur in coming years.

Do Less Harm: Evaluating HIV Programmatic Alternatives in Response to Cutbacks in Foreign Aid.

BACKGROUND: Resource-limited nations must consider their response to potential contractions in international support for HIV programs. OBJECTIVE: To evaluate the clinical, epidemiologic, and budgetary consequences of alternative HIV program scale-back strategies in 2 recipient nations, the Republic of South Africa (RSA) and Côte d'Ivoire (CI). DESIGN: Model-based comparison between current standard (CD4 count at presentation of 0.260 × 109 cells/L, universal antiretroviral therapy [ART] eligibility, and 5-year retention rate of 84%) and scale-back alternatives, including reduced HIV detection, no ART or delayed initiation (when CD4 count is <0.350 × 109 cells/L), reduced investment in retention, and no viral load monitoring or second-line ART. DATA SOURCES: Published RSA- and CI-specific estimates of the HIV care continuum, ART efficacy, and HIV-related costs. TARGET POPULATION: HIV-infected persons, including future incident cases. TIME HORIZON: 5 and 10 years. PERSPECTIVE: Modified societal perspective, excluding time and productivity costs. OUTCOME MEASURES: HIV transmissions and deaths, years of life, and budgetary outlays (2015 U.S. dollars). RESULTS OF BASE-CASE ANALYSIS: At 10 years, scale-back strategies increase projected HIV transmissions by 0.5% to 19.4% and deaths by 0.6% to 39.1%. Strategies can produce budgetary savings of up to 30% but no more. Compared with the current standard, nearly every scale-back strategy produces proportionally more HIV deaths (and transmissions, in RSA) than savings. When the least harmful and most efficient alternatives for achieving budget cuts of 10% to 20% are applied, every year of life lost will save roughly $900 in HIV-related outlays in RSA and $600 to $900 in CI. RESULTS OF SENSITIVITY ANALYSIS: Scale-back programs, when combined, may result in clinical and budgetary synergies and offsets. LIMITATION: The magnitude and details of budget cuts are not yet known, nor is the degree to which other international partners might step in to restore budget shortfalls. CONCLUSION: Scaling back international aid to HIV programs will have severe adverse clinical consequences; for similar economic savings, certain programmatic scale-back choices result in less harm than others. PRIMARY FUNDING SOURCE: National Institutes of Health and Steve and Deborah Gorlin MGH Research Scholars Award.

Improving global health - is tourism's role in poverty elimination perpetuating poverty, powerlessness and 'ill-being'?

The spectrum of challenges for public health in a global context is ever expanding. It is difficult for health professionals to keep informed about details of key issues affecting global health determinants such as poverty. Tourism is seen as one strategy to eliminate poverty in developing countries and to improve global health, but the industry struggles with keeping its promise. Apart from often negative impacts on the well-being of local communities, it also turns out not to be as altruistic as it appears at first sight. Discourses largely focus on power and control of the non-poor over the poor despite all the rhetoric to the contrary. Economic aspects still dictate the debate rather than local people's understanding of well-being. Only with a major shift in the approach to local populations, acknowledging the communities' right to self-determination and accepting them as equal partners with access to genuine benefits, will this disturbing imbalance be redressed and allow better health for more people possible. Public health professionals should question claims about the beneficial influence of tourism in poor regions and not lower their vigilance for poverty-related health problems, so that the poor are not overlooked when all other stakeholders are busy with their own agenda.

Cost Utility of Competing Strategies to Prevent Endoscopic Transmission of Carbapenem-Resistant Enterobacteriaceae.

OBJECTIVES: Prior reports have linked patient transmission of carbapenem-resistant Enterobacteriaceae (CRE, or "superbug") to endoscopes used during endoscopic retrograde cholangiopancreatography (ERCP). We performed a decision analysis to measure the cost-effectiveness of four competing strategies for CRE risk management. METHODS: We used decision analysis to calculate the cost-effectiveness of four approaches to reduce the risk of CRE transmission among patients presenting to the hospital for symptomatic common bile duct stones. The strategies included the following: (1) perform ERCP followed by US Food and Drug Administration (FDA)-recommended endoscope reprocessing procedures; (2) perform ERCP followed by "endoscope culture and hold"; (3) perform ERCP followed by ethylene oxide (EtO) sterilization of the endoscope; and (4) stop performing ERCP in lieu of laparoscopic cholecystectomy (LC) with common bile duct exploration (CBDE). Our outcome was incremental cost per quality-adjusted life year (QALY) gained. RESULTS: In the base-case scenario, ERCP with FDA-recommended endoscope reprocessing was the most cost-effective strategy. Both the ERCP with culture and hold ($4,228,170/QALY) and ERCP with EtO sterilization ($50,572,348/QALY) strategies had unacceptable incremental costs per QALY gained. LC with CBDE was dominated, being both more costly and marginally less effective vs. the alternatives. In sensitivity analysis, ERCP with culture and hold became the most cost-effective approach when the pretest probability of CRE exceeded 24%. CONCLUSIONS: In institutions with a low CRE prevalence, ERCP with FDA-recommended reprocessing is the most cost-effective approach for mitigating CRE transmission risk. Only in settings with an extremely high CRE prevalence did ERCP with culture and hold become cost-effective.

An economic evaluation of expanding hookworm control strategies to target the whole community.

BACKGROUND: The WHO treatment guidelines for the soil-transmitted helminths (STH) focus on targeting children for the control of morbidity induced by heavy infections. However, unlike the other STHs, the majority of hookworm infections are harboured by adults. This untreated burden may have important implications for controlling both hookworm's morbidity and transmission. This is particularly significant in the context of the increased interest in investigating STH elimination strategies. METHODS: We used a deterministic STH transmission model and parameter estimates derived from field epidemiological studies to evaluate the impact of child-targeted (2-14 year olds) versus community-wide treatment against hookworm in terms of preventing morbidity and the timeframe for breaking transmission. Furthermore, we investigated how mass treatment may influence the long-term programmatic costs of preventive chemotherapy for hookworm. RESULTS: The model projected that a large proportion of the overall morbidity due to hookworm was unaffected by the current child-targeted strategy. Furthermore, driving worm burdens to levels low enough to potentially break transmission was only possible when using community-wide treatment. Due to these projected reductions in programme duration, it was possible for community-wide treatment to generate cost savings - even if it notably increases the annual distribution costs. CONCLUSIONS: Community-wide treatment is notably more cost-effective for controlling hookworm's morbidity and transmission than the current child-targeted strategies and could even be cost-saving in many settings in the longer term. These calculations suggest that it is not optimum to treat using the same treatment strategies as other STH. Hookworm morbidity and transmission control require community-wide treatment.