Productivity of mother pigs is lower, and mortality greater, in countries that still confine them in gestation crates.

: For decades, pig farmers have used gestation crates to confine pregnant sows. Gestation crates physically restrain sows for most of their life, preventing them from walking or turning around. Growing concern about animal welfare has been pressuring the industry for change, with recent legislation in several countries restricting the use of crates.

Pain-Track: a time-series approach for the description and analysis of the burden of pain.

Objective: To present the Pain-Track, a novel framework for the description and analysis of the pain experience based on its temporal evolution, around which intensity and other attributes of pain (texture, anatomy), interventions and clinical symptoms can be registered. This time-series approach can provide valuable insight on the expected evolution of the pain typically associated with different medical conditions and on time-varying (risk) factors associated with the temporal dynamics of pain.

Results: We illustrate the use of the framework to explore hypotheses on the temporal profile of the pain associated with an acute injury (bone fracture), and the magnitude of the pain burden it represents.

Laying hen mortality in different indoor housing systems: a meta-analysis of data from commercial farms in 16 countries.

Societal concern with the welfare of egg laying hens housed in conventional cages is fostering a transition towards cage-free systems in many countries. However, although cage-free facilities enable hens to move freely and express natural behaviours, concerns have also been raised over the possibility that cage-free flocks experience higher mortality, potentially compromising some aspects of their welfare. To investigate this possibility, we conducted a large meta-analysis of laying hen mortality in conventional cages, furnished cages and cage-free aviaries using data from 6040 commercial flocks and 176 million hens from 16 countries.

Effect of pneumococcal conjugate vaccine introduction on childhood pneumonia mortality in Brazil: a retrospective observational study.

Background: Understanding the real-world effect of pneumococcal conjugate vaccines (PCVs) on pneumonia mortality is crucial because of the expectation that increased PCV use will substantially reduce the burden of pneumonia deaths in children younger than 5 years. However, few post-vaccine introduction studies have estimated the benefits of PCV use on childhood mortality and results have been inconsistent. Therefore, we set out to assess the effect of introduction of ten-valent pneumococcal conjugate vaccine (PCV10) on pneumonia mortality in children in Brazil.

Challenges in Estimating the Impact of Vaccination with Sparse Data.

Background: The synthetic control model is a powerful tool to quantify the population-level impact of vaccines because it can adjust for trends unrelated to vaccination using a composite of control diseases. Because vaccine impact studies are often conducted using smaller, subnational datasets, we evaluated the performance of synthetic control models with sparse time series data. To obtain more robust estimates of vaccine impacts from noisy time series, we proposed a possible alternative approach, STL+PCA method (seasonal-trend decomposition plus principal component analysis), which first extracts smoothed trends from the control time series and uses them to adjust the outcome.

We could learn much more from 1918 pandemic-the (mis)fortune of research relying on original death certificates.

Purpose: The analysis of historical death certificates has enormous potential for understanding how the health of populations was shaped by diseases and epidemics and by the implementation of specific interventions. In Brazil, the systematic archiving of mortality records was initiated only in 1944-hence the analysis of death registers before this time requires searching for these documents in public archives, notaries, parishes, and especially ancient cemeteries, which are often the only remaining source of information about these deaths. This article describes an effort to locate original death certificates in Brazil and document their organization, accessibility, and preservation.

Impact of Pneumococcal Conjugate Vaccines on Pneumonia Hospitalizations in High- and Low-Income Subpopulations in Brazil.

Background: Pneumococcal conjugate vaccines (PCVs) are being used worldwide. A key question is whether the impact of PCVs on pneumonia is similar in low- and high-income populations. However, most low-income countries, where the burden of disease is greatest, lack reliable data that can be used to evaluate the impact.

Bayesian Model Averaging with Change Points to Assess the Impact of Vaccination and Public Health Interventions.

Background: Pneumococcal conjugate vaccines (PCVs) prevent invasive pneumococcal disease and pneumonia. However, some low-and middle-income countries have yet to introduce PCV into their immunization programs due, in part, to lack of certainty about the potential impact. Assessing PCV benefits is challenging because specific data on pneumococcal disease are often lacking, and it can be difficult to separate the effects of factors other than the vaccine that could also affect pneumococcal disease rates.

Estimates of hospitalization attributable to influenza and RSV in the US during 1997-2009, by age and risk status.

Background: Estimates of influenza and respiratory syncytial virus (RSV) burden must be periodically updated to inform public health strategies. We estimated seasonal influenza- and RSV-attributable hospitalizations in the US from 1997 to 2009 according to age and risk status (NCT01599390).

Methods: Multiple linear regression modelling was used to attribute hospitalizations to influenza or RSV using virological surveillance and hospitalization data.

Estimating the population-level impact of vaccines using synthetic controls.

When a new vaccine is introduced, it is critical to monitor trends in disease rates to ensure that the vaccine is effective and to quantify its impact. However, estimates from observational studies can be confounded by unrelated changes in healthcare utilization, changes in the underlying health of the population, or changes in reporting. Other diseases are often used to detect and adjust for these changes, but choosing an appropriate control disease a priori is a major challenge.

Challenges to estimating vaccine impact using hospitalization data.

Because the real-world impact of new vaccines cannot be known before they are implemented in national programs, post-implementation studies at the population level are critical. Studies based on analysis of hospitalization rates of vaccine-preventable outcomes are typically used for this purpose. However, estimates of vaccine impact based on hospitalization data are particularly prone to confounding, as hospitalization rates are tightly linked to changes in the quality, access and use of the healthcare system, which often occur simultaneously with introduction of new vaccines.

Modelling estimates of age-specific influenza-related hospitalisation and mortality in the United Kingdom.

Background: Influenza is rarely confirmed with laboratory testing and accurate assessment of the overall burden of influenza is difficult. We used statistical modelling methods to generate updated, granular estimates of the number/rate of influenza-attributable hospitalisations and deaths in the United Kingdom. Such data are needed on a continuing basis to inform on cost-benefit analyses of treatment interventions, including vaccination.

Modelling estimates of the burden of respiratory syncytial virus infection in children in the UK.

Objective: The burden of respiratory syncytial virus (RSV) illness is not well characterised in primary care. We estimated the burden of disease attributable to RSV in children in the UK between 1995 and 2009.

Design: Time-series regression modelling.

Unintended Pregnancies in Brazil - A Challenge for the Recommendation to Delay Pregnancy Due to Zika.

Because of the potential link between the ongoing Zika virus outbreak and a surge in the number of cases of congenital microcephaly, officials in Latin America have recommended that women postpone pregnancy until this association is firmly established or the outbreak subsides. However, in all these countries a large proportion of babies are still born out of unplanned pregnancies. Teenage girls are particularly at high risk, as they often lack access to preventive contraception methods, or the knowledge to use them appropriately.

A global map of hemispheric influenza vaccine recommendations based on local patterns of viral circulation.

Both the Northern and the Southern Hemisphere annual WHO influenza vaccine recommendations are designed to ensure vaccine delivery before the winter-time peak of viral circulation in each hemisphere. However, influenza seasonal patterns are highly diverse in tropical countries and may be out of phase with the WHO recommendations for their respective hemisphere. We modelled the peak timing of influenza activity for 125 countries using laboratory-based surveillance data from the WHO's FLUNET database and compared it with the influenza hemispheric recommendations in place.

Modeling the Impact of Alternative Immunization Strategies: Using Matrices as Memory Lanes.

Existing modeling approaches are divided between a focus on the constitutive (micro) elements of systems or on higher (macro) organization levels. Micro-level models enable consideration of individual histories and interactions, but can be unstable and subject to cumulative errors. Macro-level models focus on average population properties, but may hide relevant heterogeneity at the micro-scale.

Modelling estimates of the burden of Respiratory Syncytial virus infection in adults and the elderly in the United Kingdom.

Background: Growing evidence suggests respiratory syncytial virus (RSV) is an important cause of respiratory disease in adults. However, the adult burden remains largely uncharacterized as most RSV studies focus on children, and population-based studies with laboratory-confirmation of infection are difficult to implement. Indirect modelling methods, long used for influenza, can further our understanding of RSV burden by circumventing some limitations of traditional surveillance studies that rely on direct linkage of individual-level exposure and outcome data.

Beyond crystal balls: crosscutting solutions in global health to prepare for an unpredictable future.

Background: Efforts in global heath need to deal not only with current challenges, but also to anticipate new scenarios, which sometimes unfold at lightning speed. Predictive modeling is frequently used to assist planning, but outcomes depend heavily on a subset of critical assumptions, which are mostly hampered by our limited knowledge about the many factors, mechanisms and relationships that determine the dynamics of disease systems, by a lack of data to parameterize and validate models, and by uncertainties about future scenarios.

Discussion: We propose a shift from a focus on the prediction of individual disease patterns to the identification and mitigation of broader fragilities in public health systems.

Estimates of mortality attributable to influenza and RSV in the United States during 1997-2009 by influenza type or subtype, age, cause of death, and risk status.

Background: Influenza and respiratory syncytial virus (RSV) cause substantial mortality from respiratory and other causes in the USA, especially among people aged 65 and older.

Objectives: We estimated the influenza-attributable mortality and RSV-attributable mortality in the USA, stratified by age and risk status, using outcome definitions with different sensitivity and specificity.

Methods: Influenza- and RSV-associated mortality was assessed from October 1997-March 2009 using multiple linear regression modeling on data obtained from designated government repositories.

Effect of 13-valent pneumococcal conjugate vaccine on admissions to hospital 2 years after its introduction in the USA: a time series analysis.

Background: In March 2010, 13-valent pneumococcal conjugate vaccine (PCV13) replaced the seven-valent vaccine in the USA. We assessed the effect of PCV13 use on pneumococcus-related admissions to hospital 2 years after the vaccine was introduced, when coverage in children younger than age 5 years had reached 54%.

Methods: We used data from a private inpatient discharge record database.

Use of near-real-time medical claims data to generate timely vaccine coverage estimates in the US: the dynamics of PCV13 vaccine uptake.

Background: Vaccine coverage estimates lag by years in the US. Commercially available medical claims databases contain timely records of childhood vaccinations given in physician offices. We used such data to track the replacement of the 7-valent pneumococcal conjugate vaccine (PCV7) by PCV13, a new vaccine active against 6 additional serotypes, starting in March 2010.