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Background: The pork tapeworm (Taenia solium) is a parasitic helminth that imposes a major health and economic burden on poor rural populations around the world. As recognized by the World Health Organization, a key barrier for achieving control of T. solium is the lack of an accurate and validated simulation model with which to study transmission and evaluate available control and elimination strategies. CystiAgent is a spatially-explicit agent based model for T. solium that is unique among T. solium models in its ability to represent key spatial and environmental features of transmission and simulate spatially targeted interventions, such as ring strategy. Methods/Principal findings: We validated CystiAgent against results from the Ring Strategy Trial (RST)–a large cluster-randomized trial conducted in northern Peru that evaluated six unique interventions for T. solium control in 23 villages. For the validation, each intervention strategy was replicated in CystiAgent, and the simulated prevalences of human taeniasis, porcine cysticercosis, and porcine seroincidence were compared against prevalence estimates from the trial. Results showed that CystiAgent produced declines in transmission in response to each of the six intervention strategies, but overestimated the effect of interventions in the majority of villages; simulated prevalences for human taenasis and porcine cysticercosis at the end of the trial were a median of 0.53 and 5.0 percentages points less than prevalence observed at the end of the trial, respectively. Conclusions/Significance: The validation of CystiAgent represented an important step towards developing an accurate and reliable T. solium transmission model that can be deployed to fill critical gaps in our understanding of T. solium transmission and control. To improve model accuracy, future versions would benefit from improved data on pig immunity and resistance, field effectiveness of anti-helminthic treatment, and factors driving spatial clustering of T. solium infections including dispersion and contact with T. solium eggs in the environment. Author summary: Neurocysticercosis, caused by the ingestion of Taenia solium eggs, is a major cause of human epilepsy around the world. A wide spectrum of tools to fight T. solium is are now available and include antiparasitic treatment for pigs and humans, porcine vaccines, and sanitation improvements; however, the ideal combination of interventions applied to populations to maximize effectiveness and feasibility is not known. Transmission models are one tool that can be used to compare and evaluate different intervention strategies, but no currently available T. solium models have been tested for accuracy. In this research, we validated our model ("CystiAgent") by comparing simulations of the model to the results of a large-scale trial testing a variety of T. solium control interventions. The model was calibrated using observed epidemiological data from these villages and evaluated for its ability to reproduce the effect of T. solium control interventions. The validation showed that the model was able to reproduce the baseline levels of disease, but generally overestimated the effect that each intervention would have on transmission. These results will allow us to identify limitations of the current model to improve future versions, and represent a step forward in the creation of a tool to design and evaluate future programs to control and eliminate T. solium. [ABSTRACT FROM AUTHOR]

Nitrous acid in Albequerque, NM, homes produced by unvented combustion and heterogenous reactions of nitrogen dioxide was measured. The results showed that HONO inside homes ranged from 5% to 15% of measured NO2 concentrations. Since there was a strong correlation between HONO and NO2 concentrations, it is important to consider HONO as a hazardous pollutant in homes. High concenrations of HONO due to surface-catalyzed reactions were observed.

Background: The pork tapeworm, Taenia solium, is a serious public health problem in rural low-resource areas of Latin America, Africa and Asia, where the associated conditions of nuerocysticercosis (NCC) and porcine cysticercosis cause substantial health and economic harms. An accurate and validated transmission model for T. solium would serve as an important new tool for control and elimination, as it would allow for comparison of available intervention strategies, and prioritization of the most effective strategies for control and elimination efforts. Methods: We developed a spatially-explicit agent-based model (ABM) for T. solium ("CystiAgent") that differs from prior T. solium models by including a spatial framework and behavioral parameters such as pig roaming, open human defecation, and human travel. In this article, we introduce the structure and function of the model, describe the data sources used to parameterize the model, and apply sensitivity analyses (Latin hypercube sampling-partial rank correlation coefficient (LHS-PRCC)) to evaluate model parameters. Results: LHS-PRCC analysis of CystiAgent found that the parameters with the greatest impact on model uncertainty were the roaming range of pigs, the infectious duration of human taeniasis, use of latrines, and the set of "tuning" parameters defining the probabilities of infection in humans and pigs given exposure to T. solium. Conclusions: CystiAgent is a novel ABM that has the ability to model spatial and behavioral features of T. solium transmission not available in other models. There is a small set of impactful model parameters that contribute uncertainty to the model and may impact the accuracy of model projections. Field and laboratory studies to better understand these key components of transmission may help reduce uncertainty, while current applications of CystiAgent may consider calibration of these parameters to improve model performance. These results will ultimately allow for improved interpretation of model validation results, and usage of the model to compare available control and elimination strategies for T. solium. [ABSTRACT FROM AUTHOR]

Both oral disease and middle ear infections are highly prevalent in Pacific Island children. These diseases are multifactorial and likely attributable in part to both social and environmental factors. It has been two decades since these diseases were defined in Palau, and at the time were noted to be among the most common conditions and presented a substantial burden among Palau's children. In 2006, the Ministry of Health in Palau began conducting comprehensive school health screenings in grades 1-11. While primarily used as a referral tool, this survey can also be used in epidemiologic studies to describe health trends. The current study utilized this screening data from the 2011-12 school year to characterize the prevalence of dental caries and otitis media and explore a previously suggested relationship between the two conditions, including common risk factors. It was found that over one-quarter (28.9%) of Palauan students had abnormal tympanometry results, with up to 17% indicating active otitis media. In addition, 85% of students had at least one decayed or filled tooth, with an average of 3.9 decayed or filled teeth in 12-year-olds. Both conditions were found to be more prevalent in public than in private schools; however, the two disorders were not significantly associated with each other. These findings place the prevalence of decayed, missing, and filled teeth, and otitis media in Palauan schoolchildren among the highest reported in the world. The widely recognized consequences of poor oral health and hearing impairment on learning, nutrition, and chronic disease make urgent the need for early intervention. [ABSTRACT FROM AUTHOR]

To characterize the effectiveness of a local ordinance that restricts smoking in restaurants to one third of the seating area, this study made simultaneous measurements of two markers of environmental tobacco smoke, respirable suspended particles and nicotine, in the smoking and no-smoking sections of seven restaurants. The mean concentrations of respirable suspended particles and nicotine were 40% and 65% lower, respectively, in the no-smoking than in the smoking sections, indicating substantial but not complete protection against exposure. (Am J Public Health. 1993;83:1339-1341), Having separate seating for smokers and nonsmokers in restaurants reduces but does not eliminate smoke exposure to nonsmokers. A study of both smoke particles and nicotine in the air of seven Albuquerque, NM, restaurants indicates that both nicotine and smoke particulate matter are found at varying levels. Although some of the air particles may be byproducts from preparing and serving food, ambient nicotine is associated with tobacco use. Both levels of particulate matter and nicotine were consistently lower in nonsmoking areas. The best protection from smokers was found to be a physical barrier such as a wall or room divider, but simple segregation in large rooms without barriers was found to be better than no segregation. Albuquerque's ordinance mandating segregation of smokers from nonsmokers therefore appears to be a fairly inexpensive, popular, and effective means of preserving air quality for nonsmokers.

Objective: Identify factors associated with adherence to nasoalveolar molding (NAM) therapy. Design: Retrospective case-control study. Setting: Tertiary referral center. Patients, Participants: Infants with cleft lip, with or without cleft palate, referred for NAM. One hundred thirty-five patients met criteria. Main Outcome Measure(s): Adherence to NAM therapy, defined as continuous use of the appliance and attendance of NAM adjustment visits. Results: Female sex (OR = 2.85, 95% CI 1.21-6.74), bilateral cleft (OR = 2.88, 95% CI 1.29-6.46), and travel distance (OR = 1.01, 95% CI 1.00-1.01) were independent predictors of nonadherence. Bilateral clefts (OR = 8.35, 95% CI 2.72-25.64) and public-payer insurance (OR = 3.67, 95% CI 1.13-11.91) for male patients were significantly associated with nonadherence, in our sex-stratified multivariate model. The majority of the families (58%) had public health insurance. Males comprised 77.0% of the cohort. Conclusions: NAM treatment adherence is impaired by bilateral clefts, female sex, increased travel distance, and public insurance. Further studies are warranted to investigate how these factors affect adherence, and to develop interventions to improve adherence in families at risk due to economic or psychosocial barriers. [ABSTRACT FROM AUTHOR]