Modelling the impact of school reopening and contact tracing strategies on Covid-19 dynamics in different epidemiologic settings in Brazil.

We simulate the impact of school reopening during the COVID-19 pandemic in three major urban centers in Brazil to identify the epidemiological indicators and the best timing for the return of in-school activities and the effect of contact tracing as a mitigation measure. Our goal is to offer guidelines for evidence-based policymaking. We implement an extended SEIR model stratified by age and considering contact networks in different settings - school, home, work, and community, in which the infection transmission rate is affected by various intervention measures. After fitting epidemiological and demographic data, we simulate scenarios with increasing school transmission due to school reopening, and also estimate the number of hospitalization and deaths averted by the implementation of contact tracing. Reopening schools results in a non-linear increase in reported COVID-19 cases and deaths, which is highly dependent on infection and disease incidence at the time of reopening. When contact tracing and quarantining are restricted to school and home settings, a large number of daily tests is required to produce significant effects in reducing the total number of hospitalizations and deaths. Policymakers should carefully consider the epidemiological context and timing regarding the implementation of school closure and return of in-person school activities. While contact tracing strategies prevent new infections within school environments, they alone are not sufficient to avoid significant impacts on community transmission.

Modelling optimal vaccination strategies against COVID-19 in a context of Gamma variant predominance in Brazil.

INTRODUCTION: Brazil experienced moments of collapse in its health system throughout 2021, driven by the emergence of variants of concern (VOC) combined with an inefficient initial vaccination strategy against Covid-19. OBJECTIVES: To support decision-makers in formulating COVID-19 immunization policy in the context of limited vaccine availability and evolving variants over time, we evaluate optimal strategies for Covid-19 vaccination in Brazil in 2021, when vaccination was rolled out during Gamma variant predominance. METHODS: Using a discrete-time epidemic model we estimate Covid-19 deaths averted, considering the currently Covid-19 vaccine products and doses available in Brazil; vaccine coverage by target population; and vaccine effectiveness estimates. We evaluated a 5-month time horizon, from early August to the end of December 2021. Optimal vaccination strategies compared the outcomes in terms of averted deaths when varying dose intervals from 8 to 12 weeks, and choosing the minimum coverage levels per age group required prior to expanding vaccination to younger target populations. We also estimated dose availability required over time to allow the implementation of optimal strategies. RESULTS: To maximize the number of averted deaths, vaccine coverage of at least 80 % should be reached in older age groups before starting vaccination into subsequent younger age groups. When evaluating varying dose intervals for AZD1222, reducing the dose interval from 12 to 8 weeks for the primary schedule would result in fewer COVID-19 deaths, but this can only be implemented if accompanied by an increase in vaccine supply of at least 50 % over the coming six-months in Brazil. CONCLUSION: Covid-19 immunization strategies should be tailored to local vaccine product availability and supply over time, circulating variants of concern, and vaccine coverage in target population groups. Modelling can provide valuable and timely evidence to support the implementation of vaccination strategies considering the local context, yet following international and regional technical evidence-based guidance.

Economic burden of colorectal and breast cancers attributable to lack of physical activity in Brazil.

BACKGROUND: The increasing number of cancer patients has an escalating economic impact to public health systems (approximately, International dollars- Int$ 60 billion annually in Brazil). Physical activity is widely recognized as one important modifiable risk factor for cancer. Herein, we estimated the economic costs of colon and post-menopausal breast cancers in the Brazilian Unified Health System (SUS) attributable to lack of physical activity. METHODS: Population attributable fractions were calculated using prevalence data from 57,962 adults who answered a physical activity questionnaire in the Brazilian National Health Survey, and relative risks of colon and breast cancer from a meta-analysis. Annual costs (1 Int$ = 2.1 reais) with hospitalization, chemotherapy and radiotherapy were obtained from the Hospital and Ambulatory Information Systems of the Brazilian SUS. Two counterfactual scenarios were considered: theoretical minimum risk exposure level (≥8000 MET-min/week) and physical activity guidelines (≥600 MET-min/week). RESULTS: Annually, the Brazilian SUS expended Int$ 4.5 billion in direct costs related to cancer treatment, of which Int$ 553 million due to colon and breast cancers. Direct costs related to colon and breast cancers attributable to lack of physical activity were Int$ 23.4 million and Int$ 26.9 million, respectively. Achieving at least the physical activity guidelines would save Int$ 10.3 mi (colon, Int$ 6.4 mi; breast, Int$ 3.9 mi). CONCLUSIONS: Lack of physical activity accounts for Int$ 50.3 million annually in direct costs related to colon and post-menopausal breast cancers. Population-wide interventions aiming to promote physical activity are needed to reduce the economic burden of cancer in Brazil.

Economic burden of diabetes in Brazil in 2014.

BACKGROUND: Diabetes and its complications produce significant clinical, economic and social impact. The knowledge of the costs of diabetes generates subsidies to maintain the financial sustainability of public health and social security systems, guiding research and health care priorities. AIMS: The aim of this study was to estimate the economic burden of diabetes in Brazilian adults in 2014, considering the perspectives of the public health care system and the society. METHODS: A prevalence-based approach was used to estimate the annual health resource utilization and costs attributable to diabetes and related conditions. The healthcare system perspective considered direct medical costs related to outpatient and hospitalization costs. The societal perspective considered non-medical (transportation and dietary products) and indirect costs (productivity loss, disability, and premature retirement). Outpatient costs included medicines, health professional visits, exams, home glucose monitoring, ophthalmic procedures, and costs related to end stage renal disease. The costs of hospitalization attributed to diabetes related conditions were estimated using attributable risk methodology. Costs were estimated in Brazilian currency, and then converted to international dollars (2014). RESULTS: Based on a national self-reported prevalence of 6.2%, the total cost of diabetes in 2014 was Int$ 15.67 billion, including Int$ 6.89 billion in direct medical costs (44%), Int$ 3.69 billion in non-medical costs (23.6%) and Int$ 5.07 billion in indirect costs (32.4%). Outpatient costs summed Int$ 6.62 billion and the costs of 314,334 hospitalizations attributed to diabetes and related conditions was Int$ 264.9 million. Most hospitalizations were due to cardiovascular diseases (47.9%), followed by diabetes itself (18%), and renal diseases (13.6%). Diet and transportation costs were estimated at Int$ 3.2 billion and Int$ 462.3 million, respectively. CONCLUSIONS: Our results showed a substantial economic burden of diabetes in Brazil, and most likely are underrated as they are based on an underestimated prevalence of diabetes. Healthcare policies aiming at diabetes prevention and control are urgently sought.

Cost-Utility of Gastric Bypass Surgery Compared to Clinical Treatment for Severely Obese With and Without Diabetes in the Perspective of the Brazilian Public Health System.

PURPOSE: Obesity is associated with increased morbidity and mortality. Weight loss due to gastric bypass (GBP) surgery improves clinical outcomes and may be a cost-effective intervention. To estimate the cost-effectiveness of GBP compared to clinical treatment in severely obese individuals with and without diabetes in the perspective of the Brazilian public health system. MATERIALS AND METHODS: A Markov model was developed to compare costs and outcomes of gastric bypass in an open approach to clinical treatment. Health states were living with diabetes, remission of diabetes, non-fatal and fatal myocardial infarction, and death. We also included the occurrence of complications related to surgery and plastic surgery after the gastric bypass surgery. The direct costs were obtained from primary data collection performed in three public reference centers for obesity treatment. Utility values also derived from this cohort, while transition probabilities came from the international literature. A sensitivity analysis was performed to evaluate uncertainties. The model considered a 10-year time horizon and a 5% discount rate. RESULTS: Over 10 years, GBP increased quality-adjusted life years (QALY) and costs compared to clinical treatment, resulting in an incremental cost-effectiveness ratio (ICER) of Int$1820.17/QALY and Int$1937.73/QALY in individuals with and without diabetes, respectively. Sensitivity analysis showed that utility values and direct costs of treatments were the parameters that affected the most the ICERs. CONCLUSION: The study demonstrated that GBP is a cost-effective intervention for severely obese individuals in the Brazilian public health system perspective, with a better result in individuals with diabetes.

Estimated Costs of Clinical and Surgical Treatment of Severe Obesity in the Brazilian Public Health System.

BACKGROUND: Obesity is a major global epidemic and a burden to society and health systems. This study aimed to estimate and compare the anual costs of clinical and surgical treatment of severe obesity from the perspective of the Brazilian Public Health System. METHODS: An observational and cross-sectional study was performed in three reference centers. Data collection on health resources utilization and productivity loss was carried out through an online questionnaire. Participants were divided in clinical (waiting list for a bariatric surgery) and surgical groups (open Roux-en-Y gastric bypass), and then allocated by the time of surgery (up to 1 year; 1-2 years; 2-3 years; and >3 years). Costs of visits, medications, exams, and surgeries were obtained from government sources. Data on non-medical costs, such as transportation, special diets, and caregivers, were also colleted. Productivity loss was estimated using self-reported income. Costs in local currency (Real) were converted to international dollars (Int$ 2015). RESULTS: Two hundred and seventy-four patients, 140 in surgical group and 134 in clinical group were included. In first postoperative year, the surgical group had higher costs than clinical group (Int$6005.47 [5000.18-8262.36] versus 2148.14 [1412.2-3506.8]; p = 0.0002); however, from the second year, the costs decreased progressively. In the same way, indirect costs decreased significantly after surgery (259.08 [163.63-662.72] versus 368.17 [163.62-687.27]; p = 0.06). CONCLUSION: Total costs were higher in the surgical group in the first 2 years after surgery. However, from the third year on, the costs were lower than in the clinical group.

Economic Impact of Dengue: Multicenter Study across Four Brazilian Regions.

BACKGROUND: Dengue is an increasing public health concern in Brazil. There is a need for an updated evaluation of the economic impact of dengue within the country. We undertook this multicenter study to evaluate the economic burden of dengue in Brazil. METHODS: We estimated the economic burden of dengue in Brazil for the years 2009 to 2013 and for the epidemic season of August 2012- September 2013. We conducted a multicenter cohort study across four endemic regions: Midwest, Goiania; Southeast, Belo Horizonte and Rio de Janeiro; Northeast: Teresina and Recife; and the North, Belem. Ambulatory or hospitalized cases with suspected or laboratory-confirmed dengue treated in both the private and public sectors were recruited. Interviews were scheduled for the convalescent period to ascertain characteristics of the dengue episode, date of first symptoms/signs and recovery, use of medical services, work/school absence, household spending (out-of-pocket expense) and income lost using a questionnaire developed for a previous cost study. We also extracted data from the patients' medical records for hospitalized cases. Overall costs per case and cumulative costs were calculated from the public payer and societal perspectives. National cost estimations took into account cases reported in the official notification system (SINAN) with adjustment for underreporting of cases. We applied a probabilistic sensitivity analysis using Monte Carlo simulations with 90% certainty levels (CL). RESULTS: We screened 2,223 cases, of which 2,035 (91.5%) symptomatic dengue cases were included in our study. The estimated cost for dengue for the epidemic season (2012-2013) in the societal perspective was US$ 468 million (90% CL: 349-590) or US$ 1,212 million (90% CL: 904-1,526) after adjusting for under-reporting. Considering the time series of dengue (2009-2013) the estimated cost of dengue varied from US$ 371 million (2009) to US$ 1,228 million (2013). CONCLUSIONS: The economic burden associated with dengue in Brazil is substantial with large variations in reported cases and consequently costs reflecting the dynamic of dengue transmission.