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Mathematical modelling is commonly used to evaluate infectious disease control policy and is influential in shaping policy and budgets. Mathematical models necessarily make assumptions about disease natural history and, if these assumptions are not valid, the results of these studies can be biased. We did a systematic review of published tuberculosis transmission models to assess the validity of assumptions about progression to active disease after initial infection (PROSPERO ID CRD42016030009). We searched PubMed, Web of Science, Embase, Biosis, and Cochrane Library, and included studies from the earliest available date (Jan 1, 1962) to Aug 31, 2017. We identified 312 studies that met inclusion criteria. Predicted tuberculosis incidence varied widely across studies for each risk factor investigated. For population groups with no individual risk factors, annual incidence varied by several orders of magnitude, and 20-year cumulative incidence ranged from close to 0% to 100%. A substantial proportion of modelled results were inconsistent with empirical evidence: for 10-year cumulative incidence, 40% of modelled results were more than double or less than half the empirical estimates. These results demonstrate substantial disagreement between modelling studies on a central feature of tuberculosis natural history. Greater attention to reproducing known features of epidemiology would strengthen future tuberculosis modelling studies, and readers of modelling studies are recommended to assess how well those studies demonstrate their validity.

Influenza vaccination aims to prevent infection by influenza virus and reduce associated morbidity and mortality; however, vaccine effectiveness (VE) can be modest, especially for subtype A(H3N2). Low VE has been attributed to mismatches between the vaccine and circulating influenza strains and to the vaccine’s elicitation of protective immunity in only a subset of the population. The low H3N2 VE in the 2012-2013 season was attributed to egg-adaptive mutations that created antigenic mismatch between the actual vaccine strain (IVR-165) and both the intended vaccine strain (A/Victoria/361/2011) and the predominant circulating strains (clades 3C.2 and 3C.3).

The Unified Health System (Sistema Único de Saúde (SUS)) has enabled substantial progress towards Universal Health Coverage (UHC) in Brazil. However, structural weakness, economic and political crises and austerity policies that have capped public expenditure growth are threatening its sustainability and outcomes. This paper analyses the Brazilian health system progress since 2000 and the current and potential effects of the coalescing economic and political crises and the subsequent austerity policies. We use literature review, policy analysis and secondary data from governmental sources in 2000-2017 to examine changes in political and economic context, health financing, health resources and healthcare service coverage in SUS. We find that, despite a favourable context, which enabled expansion of UHC from 2003 to 2014, structural problems persist in SUS, including gaps in organisation and governance, low public funding and suboptimal resource allocation. Consequently, large regional disparities exist in access to healthcare services and health outcomes, with poorer regions and lower socioeconomic population groups disadvantaged the most. These structural problems and disparities will likely worsen with the austerity measures introduced by the current government, and risk reversing the achievements of SUS in improving population health outcomes. The speed at which adverse effects of the current and political crises are manifested in the Brazilian health system underscores the importance of enhancing health system resilience to counteract external shocks (such as economic and political crises) and internal shocks (such as sector-specific austerity policies and rapid ageing leading to rise in disease burden) to protect hard-achieved progress towards UHC.

Reliable prognostic markers for predicting severity of allergic reactions during oral food challenges (OFCs) have not been established.