Vaccine Myths: Setting the Record Straight

Despite their standing as one of the most remarkable public health achievements, vaccines have been surrounded by dangerous myths since the development of the smallpox vaccine in the 18th century. In recent decades, with the publication of a fraudulent article linking vaccines to autism, the involvement of celebrities in the debate, and the rise of the internet and social media as sources for information for patients, these myths have become more widespread. This paper reviews four common vaccine myths: vaccines cause autism, vaccines are not safe, too many vaccines are given too soon, and the influenza vaccine is not necessary. For each of these myths, we review the origin and spread of misinformation. The authors then present the scientific evidence against each myth. Extensive research has found no link between vaccines, and particularly the MMR vaccine or the preservative thimerosal, and autism. The U.S. and world health agencies have effective mechanisms in place to review and monitor vaccine safety. These systems have worked to detect and evaluate even rare vaccine adverse events. The recommended vaccine schedule is safe for infants’ immune systems. The flu vaccine is an essential tool in the fight against the seasonal influenza deaths. A consequence of these myths is that parents are choosing to delay or refuse recommended vaccines for themselves and their children. This has resulted in outbreaks of measles, pertussis, H. influenza type b, varicella, and pneumococcal disease in the United States. Unvaccinated and undervaccinated children risk contracting the disease themselves, and pose a risk to their community as herd immunity decreases. It is important to explore and refute the myths leading to decreased vaccination rates, so health care providers and parents can make educated decisions to protect children and ensure public health

Feeding Practices and Growth of Children Under 20 Months of Age in Madrid.

The feeding habits of 344 children under 20 months of age were obtained from mothers using the dietary history method supplemented with questions on milk feeding and weaning. Infants were remarkably similarly fed. No relations were found between breast-feeding and socioeconomic group, age of the mother or sex of the baby. Neither did socioeconomic group, sex or birth weight of the baby influence the timing of complementary feeding; however, the latter was significantly correlated to both mother's age and feeding method at the age of three months. In addition, six anthropometric measurements of the children were taken. These anthropometric results showed that the children were, on average, taller and heavier, but leaner than those of relevant national and international growth references. Fifty one samples of home-prepared baby meals together with 46 food diaries of infants of seven and eight months were collected. The meals were analysed chemically and the diaries were calculated for daily intake of energy, macronutrients and six minerals. The meals had high protein but low fat content, with accordingly a low energy density. The children's mean daily nutrient intake showed also high protein and low fat levels due to the meals; nevertheless, intakes of energy and minerals were adequate. About 20% of the baby meals had a high sodium level. Children in this study were apparently well-fed and thriving. Compliance with present guidelines on infant nutrition is high, just minor changes are needed to improve actual practices: breast-feeding should last longer, complementary foods should be introduced later and salt and sugar should be avoided in baby meals. Mothers, particularly those in the low socioeconomic group, need better understanding of gluten and its introduction into the infant's diet

Estimation of fiber diameters in the spinal dorsal columns from clinical data

Lack of human morphometric data regarding the largest nerve fibers in the dorsal columns (DCs) of the spinal cord has lead to the estimation of the diameters of these fibers from clinical data retrieved from patients with a new spinal cord stimulation (SCS) system. These patients indicated the perception threshold of stimulation induced paresthesia in various body segments, while the stimulation amplitude was increased. The fiber diameters were calculated with a computer model, developed to calculate the effects of SCS on spinal nerve fibers. This computer model consists of two parts: (1) a three-dimensional (3-D) volume conductor model of a spinal cord segment in which the potential distribution due to electrical stimulation is calculated and (2) an electrical equivalent cable model of myelinated nerve fiber, which uses the calculated potential field to determine the threshold stimulus needed for activation. It is shown that the largest fibers in the medial DCs are significantly smaller than the largest fibers in the lateral parts. This finding is in accordance with the fiber distribution in cat, derived from the corresponding propagation velocities. Moreover, it is shown that the mediolateral increase in fiber diameter is mainly confined to the lateral parts of the DCs. Implementation of this mediolateral fiber diameter distribution of the DCs in the computer model enables the prediction of the recruitment order of dermatomal paresthesias following increasing electrical stimulation amplitud

Bayesian clustering of multiple zero-inflated outcomes

Several applications involving counts present a large proportion of zeros (excess-of-zeros data). A popular model for such data is the hurdle model, which explicitly models the probability of a zero count, while assuming a sampling distribution on the positive integers. We consider data from multiple count processes. In this context, it is of interest to study the patterns of counts and cluster the subjects accordingly. We introduce a novel Bayesian approach to cluster multiple, possibly related, zero-inflated processes. We propose a joint model for zero-inflated counts, specifying a hurdle model for each process with a shifted Negative Binomial sampling distribution. Conditionally on the model parameters, the different processes are assumed independent, leading to a substantial reduction in the number of parameters as compared with traditional multivariate approaches. The subject-specific probabilities of zero-inflation and the parameters of the sampling distribution are flexibly modelled via an enriched finite mixture with random number of components. This induces a two-level clustering of the subjects based on the zero/non-zero patterns (outer clustering) and on the sampling distribution (inner clustering). Posterior inference is performed through tailored Markov chain Monte Carlo schemes. We demonstrate the proposed approach on an application involving the use of the messaging service WhatsApp. This article is part of the theme issue 'Bayesian inference: challenges, perspectives, and prospects'

A systematic analysis on tomato powder quality prepared by four conductive drying technologies

Four pilot-scale conductive dryers, namely a vacuum drum dryer (VDD), a drum dryer (DD), an agitated thin film dryer (ATFD) and a refractance window dryer (RWD), were used to dry tomato puree. Drying induced colour differences between the reconstituted puree and the original puree and strongly affected the volatile and non- volatile profiles of the powders. Principal component analysis (PCA) identified four separated groups corresponding to the different drying methods, indicating that the drying methods caused significant variance in compound profiles. Subsequently, pairwise comparison of different dried powders was performed by partial least square discriminant analysis (PLS-DA). This resulted in a selection of discriminative volatile and non-volatile markers. RWD and VDD produced powders with high volatile markers that may be related to aroma retention. Conversely, DD dried products contained more non-volatile markers that can be related to taste perception. ATFD processed powders had a lower level of discriminant compounds. Industrial relevance: Tomato products are frequently thermally processed and dehydrated. However, processing negatively affects the sensory quality of tomato products. In this study, four conductive drying processes, i.e. vacuum drum drying (VDD), drum drying (DD), agitated thin film drying (ATFD) and refractance window drying (RWD) were studied for being energy-efficient drying methods, while suitable for mild (e.g. due to the reduced pressure) drying of pastes and slurries, such as tomato puree. The pilot-scale drying experiments and subsequent statistical analyses of results on quality markers contributed to unravel the impact of the different conductive drying technologies on tomato powder quality. This study may be considered a starting point for selection of conductive drying technologies for the efficient production of high quality tomato powders and other vegetable powders

Solitary magnetic perturbations at the ELM onset

Edge localised modes (ELMs) allow maintaining sufficient purity of tokamak H-mode plasmas and thus enable stationary H-mode. On the other hand in a future device ELMs may cause divertor power flux densities far in excess of tolerable material limits. The size of the energy loss per ELM is determined by saturation effects in the non-linear phase of the ELM, which at present is hardly understood. Solitary magnetic perturbations (SMPs) are identified as dominant features in the radial magnetic fluctuations below 100kHz. They are typically observed close (+-0.1ms) to the onset of pedestal erosion. SMPs are field aligned structures rotating in the electron diamagnetic drift direction with perpendicular velocities of about 10km/s. A comparison of perpendicular velocities suggests that the perturbation evoking SMPs is located at or inside the separatrix. Analysis of very pronounced examples showed that the number of peaks per toroidal turn is 1 or 2, which is clearly lower than corresponding numbers in linear stability calculations. In combination with strong peaking of the magnetic signals this results in a solitary appearance resembling modes like palm tree modes, edge snakes or outer modes. This behavior has been quantified as solitariness and correlated to main plasma parameters. SMPs may be considered as a signature of the non-linear ELM-phase originating at the separatrix or further inside. Thus they provide a handle to investigate the transition from linear to non-linear ELM phase. By comparison with data from gas puff imaging processes in the non-linear phase at or inside the separatrix and in the scrape-off-layer (SOL) can be correlated. A connection between the passing of an SMP and the onset of radial filament propagation has been found. Eventually the findings related to SMPs may contribute to a future quantitative understanding of the non-linear ELM evolution.Comment: submitted to Nuclear Fusio

Societal burden and quality of life in patients with Lisfranc Injuries

Background: The incidence of Lisfranc fractures is rising, along with the incidence of foot fractures in general. These injuries can lead to long-term healthcare use and societal costs. Current economic evaluation studies are scarce in Lisfranc fracture research, and only investigate the healthcare costs. The aim of the present study was to accurately measure the monetary societal burden of disease and quality of life in the first 6 months after the injury in patients with Lisfranc fractures in the Netherlands. Materials and methods: This study used a prevalence-based, bottom-up approach. Patients were included through thirteen medical centres in the Netherlands. Both stable and unstable injuries were included. The societal perspective was used. The costs were measured at baseline, 12 weeks and 6 months using the iMTA MCQ and PCQ questionnaires. Reference prices were used for valuation. Quality-of-life was measured using the EQ-5D-5 L and VAS scores. Results: 214 patients were included. The mean age was 45.9 years, and 24.3% of patients had comorbidities. The baseline questionnaires yielded approximately €2023 as the total societal costs in the 3 months prior to injury. The follow-up questionnaires and surgery costs assessment yielded approximately €17,083 as the total costs in the first 6 months after injury. Of these costs, approximately two thirds could be attributed to productivity losses. The EQ-5D-5 L found a mean index value of 0.449 at baseline and an index value of 0.737 at the 6-month follow-up. Conclusion: The total monetary societal costs in the first 6 months after injury are approximately €17,083. Approximately two thirds of these costs can be attributed to productivity losses. These costs appear to be somewhat higher than those found in other studies. However, these studies only included the healthcare costs. Furthermore, the baseline costs indicate relatively low healthcare usage before the injury compared to the average Dutch patient. The mean QoL index was 0.462 at baseline and 0.737 at 6 months, indicating a rise in QoL after treatment as well as a long-lasting impact on QoL. To our knowledge, this is only the first study investigating the societal costs of Lisfranc injuries, so more research is needed.</p