Search

Background: Community water fluoridation began in the 1945 as a public health measure to prevent and control caries and was implemented in Israel in 1981. Community water fluoridation reduced caries significantly, but in 2014, the Ministry of Health decided to stop Community water fluoridation in Israel. The aim of our study was to examine the effect of fluoridation cessation on the dental health of children aged 3–5, treated in "Assuta Tel Aviv" dental clinics, under general anesthesia or deep sedation. Methods: The computerized Maccabi-Dent database provided data for this retrospective study. Records from the years 2014–2019 including treatment codes for procedures relevant to the study, the number of stainless-steel crowns and restorations of all types were examined. Kruskal-Wallis test was performed to compare the results from before and after fluoridation cessation. Results: A statistically significant increase in the mean number of treatments in the years after fluoridation cessation (P < 0.05) was found. There was approximately a two-fold increase in the number of all treatments for all ages. Conclusion: The results of the study emphasize the advantages of water fluoridation and are further proof of the need to restore community water fluoridation in Israel. [ABSTRACT FROM AUTHOR]

Purpose: The post-pandemic management of COVID-19 infections and any emergent outbreaks is because this endemic disease remains a public health concern. Vaccine hesitancy may continue to hamper efforts to respond to any new disease outbreaks and future epidemics. This qualitative study aimed to explore the factors influencing COVID-19 vaccine acceptance and hesitancy in Kenya to gain deeper insights into this issue. Methods: This study was implemented in western Kenya using key informant interviews. Fourteen (14) key informants were purposively selected for this study. All interviews were transcribed and analyzed using thematic analysis. The interpretation of findings was conducted within the framework of the Health Belief Model. Key findings: Knowledge was a critical factor in combatting misinformation and fostering vaccine acceptance among participants in this study. Misinformation included rumors that the vaccine lowers immunity and was intended for population control. Cues to action included influence from political and opinion leaders and observing the loss of life among unvaccinated individuals. Perceived barriers to vaccine uptake included fear of vaccine safety, side effects, long waiting times at the time of our study, fear of contracting COVID-19 at vaccination sites, family/spousal influence on vaccine uptake and fear of the unknown with the vaccine. Conclusions: The findings from this study provide insight into areas for targeted strategies for managing COVID-19 vaccinations and future pandemics. Within the framework of the Health Belief Model, this study identified salient barriers and facilitators of COVID-19 vaccine hesitancy that may be helpful to inform future pandemic responses. [ABSTRACT FROM AUTHOR]

Copyright of Annali di Igiene, Medicina Preventiva e di Comunità is the property of Societa Editrice Universo s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annali di Igiene, Medicina Preventiva e di Comunità is the property of Societa Editrice Universo s.r.l. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seasonal influenza is an acute respiratory infection caused by the influenza virus which constitutes a significant public health issue associated with high morbidity and mortality. The aim of this study was to investigate changes in attitudes, perceptions, and practices regarding influenza vaccination in the Spanish adult population during the COVID-19 pandemic, as well as their vaccination intentions, with special attention paid to those over 65 years old and in high-risk groups. To this end, a cross-sectional study was conducted through 2219 telephone interviews, and the results were compared with results obtained a year earlier. Regarding the reasons for deciding to get vaccinated in the 2022/23 season, a significant increase was observed in vaccine confidence (36.7% vs. 42.8%), social responsibility (32.5% vs. 43.8%), and in awareness of the importance of vaccination due to COVID-19 (21.7% vs. 25.4%). Advanced age (OR 2.8, 95% CI 2.0–3.9), belonging to high-risk groups (OR 2.7, 95% CI 2.0–3.7), and prior vaccination (OR 25.3, 95% CI 19.5–32.7) emerged as significant predictors for the intent to receive the influenza vaccine in the 2022/23 season. Continuously observing shifts in perceptions and behaviors related to influenza immunization is crucial to pinpoint factors that may influence the willingness to receive the vaccine and, in this way, design public health strategies that achieve a greater acceptance of it. [ABSTRACT FROM AUTHOR]

Objectives: Community water fluoridation has been associated with better oral health conditions globally and reduced dental caries. While oral health policies are governed by the health sector agenda, water fluoridation is undertaken by public, private, and mixed public/private companies of the sanitation sector. The first aim of this study was to investigate the degree of intersectoral collaboration, and the second was to investigate how the coordination mechanisms are perceived by the sanitation agents of the sectors involved in water quality management, for the potential establishment of water fluoridation in a central‐west state in Brazil. Methods: Semi‐structured interviews were conducted with chief sanitation agents from nonprofit, profit, and mixed public/private companies responsible for water quality and fluoridation in a purposive sample. Theoretical frameworks of intersectoral collaboration and coordination mechanisms were used for analysis. Results: Twelve interviews were conducted. Informal collaboration was identified in the sanitation sector within companies involved in water provision. The main coordination mechanisms were network‐type mechanisms, which involve consultations and knowledge sharing, and market‐type mechanisms, which explore new job opportunities and cost‐effectiveness, especially in water quality measures. Enabling themes (enablers) were identified, such as positive attitude toward including water quality and fluoridation in a collaborative health and sanitation common agenda. Moreover, fluoridation did not meet the regulatory and surveillance agenda at the state level, and until that moment, there was no proposal of the health sector for water fluoridation. Conclusions: Partnership creation, consolidation, and shared mission, especially between health and sanitation sectors, were identified as main challenges for implementing water fluoridation policy. [ABSTRACT FROM AUTHOR]

Background: Among the methods currently available to provide fluoride in population levels, fluoridated water is the most successful for presenting high efficacy, safety and good cost–benefit. However, recent studies on external control have shown great variability of fluoride concentrations in the water from treatment stations in Brazilian cities, which must present concentration between 0.6 and 0.8 mg/L to be considered acceptable in most cities. Thus, this study aimed to perform a systematic review of the literature to assess the adequacy of fluoride concentration in the water in Brazilian cities using external control. Methods: The protocol was registered in PROSPERO. Six databases were used as primary search sources and three databases were used to partially capture the "gray literature". Only observational studies that assessed the fluoride concentration of artificially fluoridated water from the public supply network were included. The JBI Critical Appraisal Tools for Systematic Reviews was used to assess the risk of bias of the studies. A proportion meta-analyses using random-effect models were performed. The heterogeneity between studies was determined by I2 statistic. Meta-regressions were conducted to identify relevant moderators to be used in stratified meta-analyses. Publication bias was investigated by Egger's tests. Results: The search provided 2038 results, from which 14 met the eligibility criteria and were included in the data extraction of the review. Overall, the water samples were collected from 449 different sources in three Brazilian regions. Thirteen studies presented a low risk of bias. The mean concentration of fluoride ranged from 0.17 to 0.89 ppmF. The meta-analyis demonstrated that more than half of the water samples analyzed had fluoride concentration levels outside the acceptable range (56.6%; 95% CI 45.5; 67.3), with high heterogeneity. Conclusion: More than half of the public water supply analyzed in the studies selected had fluoride concentration levels outside the acceptable range, which may affect the risk of developing oral diseases in the Brazilian population, having an important impact on public health. [ABSTRACT FROM AUTHOR]

Objective: The increased availability of fluoride and concern over the impact of fluorosis, have led to guidance suggesting a decrease or cease in the optimal concentration of fluoride in water fluoridation schemes. To date there have been no systematic reviews looking at both impact of fluoride reduction and total cessation. This review aimed to examine the impact of stopping or reducing the level of fluoride in public water supplies on dental fluorosis.Content: Multiple databases were searched (MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and the Web of Science). Two reviewers independently screened sources, extracted data and assessed study quality. Results were synthesised qualitatively and quantitatively. The main outcome measure was the prevalence of dental fluorosis.Summary: Six studies of cross-sectional design were included. Two studies were scored as evidence level B (moderate) and the remaining four publications were evidence level C (poor). Meta-analysis indicated fluorosis prevalence was significantly decreased following either a reduction in the concentration of fluoride or cessation of adding fluoride to the water supply (OR:6.68; 95% CI:2.48 to 18.00).Outlook: The evidence suggests a significant decrease in the prevalence of fluorosis post cessation or reduction in the concentration of fluoride added to the water supply. However, this work demonstrates that when studies are subject to current expectations of methodological and experimental rigour, there is limited evidence with low methodological quality to determine the effect of stopping or reducing the concentration of fluoride in the water supply on dental fluorosis. [ABSTRACT FROM AUTHOR]

Background: Water fluoridation (WF) has been a national caries prevention program in Malaysia since 1972. However, between July 2012 and December 2013, WF was discontinued in Pahang. This study aimed to compare caries prevalence and mean caries experience among Malaysian children in WF and WF-ceased areas and determine its associated risk factors. Methods: This cross-sectional study was conducted among 12-year-old schoolchildren in two Malaysian states: Pahang (WF-ceased) and Perak (WF-continued). Dental caries was examined using ICDAS criteria, and a questionnaire was used to collect relevant data. Associations between independent variables and dental caries were analyzed by simple logistic regression and general linear model analyses. Results: Dental caries (D4-6MFT) was significantly higher among children in WF-ceased areas than in communities where WF continued. Multivariate analysis demonstrated that exposure to WF remains a strong predictor of low caries experience among the study population. Moreover, children with irregular toothbrushing frequency before sleep and whose parents have lower educational attainment are associated with higher caries experience. Conclusion: Caries prevalence and mean caries experience were significantly higher among children in WF-ceased areas than in communities where WF continued. Multivariate analysis revealed that several factors were associated with caries experience. [ABSTRACT FROM AUTHOR]

Before 2002, there had been a long-term stalemate between private water companies and District Health Authorities across England. Between 2002 and 2005 the team in the Office of the Chief Dental Officer used leadership and advocacy skills to overcome political barriers, introducing the Water Act 2003 and a Statutory Instrument in 2005 providing indemnity for water companies. This legislation was key in removing obstacles towards the expansion water fluoridation across England. [ABSTRACT FROM AUTHOR]

Though controversial, water fluoridation has been hailed as one of the top-ten public-health achievements of the 20th century in the United States of America. In this article, we aim to investigate the public sense of water fluoridation as reflected on Twitter, using data from 2009 to 2017. To this end, tweets related to water fluoridation were collected using queries such as "fluoridated water or fluoride water," "water fluoridation or fluoridation of water," and hashtags related to water fluoridation. The collected tweets (n = 218,748) were examined through informetric, linguistic (word sentiment, word frequency, and word network analyses), and issue tweet analyses. We found that Twitter users who tweeted about water fluoridation in English between 2009 and 2017 constituted about <0.01% of all users including non-English users. In their tweets, words such as "poison" and "waste" were the strong negative sentiment words most often used. Of the top 30 words most frequently used, words related to information sources on water fluoridation and the safety of water fluoridation appeared more often than words related to its efficacy. Additionally, the words related to information sources on water fluoridation and the safety of water fluoridation were found to be core terms in the sentences of tweet mentions. Our linguistic analyses indicate that Twitter users responded sensitively to words that emphasize negative aspects of fluoridation. This is clearly shown in our issue tweet analysis, where tweet mentions expressing negative opinions about water fluoridation accounted for at least 59.2% of all mentions. By contrast, <15% of tweet mentions were found to be positive. These findings suggest that professionals need to reevaluate the current state of online information about water fluoridation, and improve it in a way so that the public can easily access reliable information sources. [ABSTRACT FROM AUTHOR]

Our understanding of the complexity of the oral biome and of the role of the various constituent bacteria in the aetiology of dental disease is growing. Probiotics and their relationship with prebiotics, as well as other microbiome‐based interventions, could be useful in preventing and treating dental disease and in promoting oral health. However, given the promise and early stage of this treatment approach, there are also a number of ethical, social and regulatory issues associated with innovative probiotic therapy. In this article, a brief update is given on contemporary theories of the aetiology and management of the two commonest dental diseases, and on the roles of pre‐ and probiotics and oral biome transplant in the management of these diseases. The focus is primarily on four core issues: informed consent, risk–benefit assessment, how to determine suitable healthy donors, and commercialization and regulation. We discuss the safety and benefits of oral probiotics, not only concerning the products and quality control during their manufacture, but also regarding the depth of public knowledge about this topic. We point out that the requirement of listing ingredients honestly might be insufficient, and that the prevalent rhetoric of 'natural' and 'organic' as well as some health claims in the translational, innovative probiotic industry and markets are themselves misleading and should be carefully scrutinized. Finally, we suggest an ethical imperative to find a balance between scientific research and industry, and public health in the regulation of probiotics. [ABSTRACT FROM AUTHOR]

Copyright of Review of Policy Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water fluoridation has been cited as one of the top 10 public health achievements of the 20th century. Herein, we analyzed water fluoridation articles related to dental caries published in PubMed between 1950 and 2016 using informetrics and linguistic methods to investigate trends in the studies. To this aim, queries such as "dental caries and (water fluoridation or fluoridated water)," "dental caries and (fluoride or fluoridation)," and "dental caries" were submitted to PubMed to retrieve information about articles on water fluoridation within the area of dental caries and fluoride - their titles, abstracts, publication dates, author affiliations, and publication journals. This article information was then collected by an automatic web crawler and examined through informetrics and linguistic analyses. It was found that the number of articles concerned with water fluoridation and dental caries was 3,381 and declined over time after 1970. The articles were published by 750 journals - most notably, Community Dentistry and Oral Epidemiology and Caries Research. With regard to the geographic distribution of the authors, Europe and North America, especially the USA and UK, accounted for 59.9% of the articles published during the years 1987 to 2015, though there was a sharp increase in the number of authors in Oceania and Asia in recent years. In the titles and abstracts of the articles, "community" and "fluorosis" were mentioned more frequently than the other key terms selected in this study, regardless of the period examined. Our findings may allow one to assess how the research on water fluoridation has evolved over the past several decades. [ABSTRACT FROM AUTHOR]

The article presents an American Association for Dental Research (AADR) Policy Statement on community water fluoridation (CWF). Topics include the missions of the AADR, issues related to dental, oral, and craniofacial health and research, information about fluoride and fluoridation chemistry, as well as the dental and health effects of CWF.

Fluoridation of America's drinking water was among the great public health achievements of the 20th century. Yet there is a paucity of studies from the past 3 decades investigating its dental health benefits in the U.S.Population: This cross-sectional study sought to evaluate associations between availability of community water fluoridation (CWF) and dental caries experience in the U.S. child and adolescent population. County-level estimates of the percentage of population served by CWF (% CWF) from the Centers for Disease Control and Prevention's Water Fluoridation Reporting System were merged with dental examination data from 10 y of National Health and Nutrition Examination Surveys (1999 to 2004 and 2011 to 2014). Dental caries experience in the primary dentition (decayed and filled tooth surfaces [dfs]) was calculated for 7,000 children aged 2 to 8 y and in the permanent dentition (decayed, missing, and filled tooth surfaces [DMFS]) for 12,604 children and adolescents aged 6 to 17 y. Linear regression models estimated associations between % CWF and dental caries experience with adjustment for sociodemographic characteristics: age, sex, race/ethnicity, rural-urban location, head-of-household education, and period since last dental visit. Sensitivity analysis excluded counties fluoridated after 1998. In unadjusted analysis, caries experience in the primary dentition was lower in counties with ≥75% CWF (mean dfs = 3.3; 95% confidence limit [CL] = 2.8, 3.7) than in counties with <75% CWF (mean dfs = 4.6; 95% CL = 3.9, 5.4), a prevented fraction of 30% (95% CL = 11, 48). The difference was also statistically significant, although less pronounced, in the permanent dentition: mean DMFS (95% CL) was 2.2 (2.0, 2.4) and 1.9 (1.8, 2.1), respectively, representing a prevented fraction of 12% (95% CL = 1, 23). Statistically significant associations likewise were seen when % CWF was modeled as a continuum, and differences tended to increase in covariate-adjusted analysis and in sensitivity analysis. These findings confirm a substantial caries-preventive benefit of CWF for U.S. children and that the benefit is most pronounced in primary teeth. [ABSTRACT FROM AUTHOR]

In May of 2011, a decision was made by city council in Calgary, Canada, to cease community water fluoridation and to re-allocate the annual operating costs to targeted dental programming. The purpose of this study was to critically analyze this decision as an example of a shift from a universal approach (fluoridation) to a targeted approach (dental programming delivered to children in low-income communities). We were especially interested in how the concept of equity played out in the deliberations, and we used Hilary Graham’s three conceptualizations of equity as a framework. We examined publicly available municipal council documents pertaining to this policy decision, with a prominent focus on the 26 January 2011 meeting of the Standing Policy Committee on Utilities and Environment at which Calgarians (citizens and professionals) were invited to speak. We extracted and critiqued statements or exchanges pertaining to equity or related concepts (e.g. poverty). We observed different perspectives on the concept of equity, and the notion of community water fluoridation as equitable. In particular, there was a tendency, expressed strongly by some participants in the debate, to conflate equity and poverty (Graham’s ‘disadvantages’ conceptualization of equity), such that a targeted approach was seen as the only viable way of addressing the dental health needs of children living in poverty. This research is timely considering the apparently increasing frequency of cessation of fluoridation in Canada, the consequent search for alternative approaches to preventive dental health, and the apparently strong appeal of a targeted approach. [ABSTRACT FROM PUBLISHER]

Water fluoridation is a controversial issue in public health. Despite the uncertainty regarding its efficacy and safety, health officials continue to communicate it as ‘unequivocally’ safe and effective. Our focus is on how health officials and policy-makers in Israel frame the issue of water fluoridation in terms of certainty while promoting a mandatory fluoridation policy. According to van Asselt and Vos, the uncertainty paradox describes situations in which uncertainty is acknowledged, but the role of science is framed as providing certainty. Our study is an analysis of documents and media articles emphasizing the paradoxical language used by official representatives on the controversial topic of fluoridation. A central contribution of this study is that we coin the term ‘uncertainty bias,’ in which policy-makers do exactly what they accuse laypeople of doing, framing uncertainty in biased terms. We found that in order to establish mandatory regulation, health ministry officials expressed information in an unbalanced format, promoting the topic of fluoridation by framing it in exclusively positive terms. This study does not focus on the practice of water fluoridation per se, and is not intended to decide for or against it, but rather, to explore how the debate regarding it is communicated. Understanding this particular case can shed light on how other controversial topics are transformed into health policy that is characterized in equivocal terms. [ABSTRACT FROM AUTHOR]

Background: Implementing community water fluoridation involves costs, but these need to be considered against the likely benefits. We aimed to assess the cost-benefit and cost-effectiveness of water fluoridation in New Zealand (NZ) in terms of expenditure and quality-adjusted life years. Methods: Based on published studies, we determined the risk reduction effects of fluoridation, we quantified its health benefits using standardised dental indexes, and we calculated financial savings from averted treatment. We analysed NZ water supplies to estimate the financial costs of fluoridation. We devised a method to represent dental caries experience in quality-adjusted life years. Results: Over 20 years, the net discounted saving from adding fluoride to reticulated water supplies supplying populations over 500 would be NZ$1401 million, a nine times pay-off. Between 8800 and 13,700 quality-adjusted life years would be gained. While fluoridating reticulated water supplies for large communities is cost-effective, it is unlikely to be so with populations smaller than 500. Conclusions: Community water fluoridation remains highly cost-effective for all but very small communities. The health benefits--while (on average) small per person--add up to a substantial reduction in the national disease burden across all ethnic and socioeconomic groups. [ABSTRACT FROM AUTHOR]

Background Over the last two decades, progress in prevention and treatment of caries and periodontal diseases has been translated to better oral health and improved tooth retention in the adult population. The ageing population and the increasing expectations of good oral health-related quality of life in older age pose formidable challenges to clinical care and healthcare systems. Aims The objective of this workshop was to critically review scientific evidence and develop specific recommendations to: (i) prevent tooth loss and retain oral function through prevention and treatment of caries and periodontal diseases later in life and (ii) increase awareness of the health benefits of oral health as an essential component of healthy ageing. Methods Discussions were initiated by three systematic reviews covering aspects of epidemiology of caries and periodontal diseases in elders, the impact of senescence on caries and periodontal diseases and the effectiveness of interventions. Recommendations were developed based on evidence from the systematic reviews and expert opinion. Results Key messages included: (i) the ageing population, trends in risk factors and improved tooth retention point towards an expected increase in the total burden of disease posed by caries and periodontal diseases in the older population; (ii) specific surveillance is required to monitor changes in oral health in the older population; (iii) senescence impacts oral health including periodontitis and possibly caries susceptibility; (iv) evidence indicates that caries and periodontal diseases can be prevented and treated also in older adults; (v) oral health and functional tooth retention later in life provides benefits both in terms of oral and general quality of life and in terms of preventing physical decline and dependency by fostering a healthy diet; (vi) oral healthcare professionals and individuals should not base decisions impacting tooth retention on chronological age but on level of dependency, life expectancy, frailty, comfort and quality of life; and (vii) health policy should remove barriers to oral health care for vulnerable elders. Conclusions Consensus was reached on specific actionable priorities for public health officials, oral healthcare professionals, educators and workforce planners, caregivers and relatives as well as for the public and ageing patients. Some priorities have major implications for policymakers as health systems need to adapt to the challenge by systemwide changes to enable (promote) tooth retention later in life and management of deteriorating oral health in increasingly dependent elders. [ABSTRACT FROM AUTHOR]

Systematic reviews have found no evidence to support a benefit of water fluoridation (WF) to prevent dental caries in adult populations. The aim of this natural experiment was to investigate whether lifetime access to fluoridated water is associated with dental caries experience among adults from Florianópolis, Brazil. The data originated from a population-based cohort study (EpiFloripa Adult) initiated in 2009 (n = 1,720) when participants were aged 20 to 59 years. The second wave was carried out in 2012 (n = 1,140) and included a dental examination and a face-to-face questionnaire. Participants residing at the same address since the age of 7 y or before were included in the primary analyses. Sensitivity analyses were also performed. WF was implemented in the city in 2 different periods of time: 1982 (60% of the population) and 1996. Dental caries was assessed by the decayed, missing, and filled teeth (DMFT) index. A combination of residential status, participant’s age, and year of implementation of WF permitted the creation of participants’ lifetime access to fluoridated water: >75%, 50% to 75%, and <50% of a participant’s lifetime. Covariates included sex, age, socioeconomic mobility, educational attainment, income, pattern of dental attendance, and smoking. Participants who accessed fluoridate water <50% of their lifetime presented a higher mean rate ratio of DMFT (1.39; 95% CI, 1.05–1.84) compared with those living >75% of their lifetime with residential access to fluoridated water. Participants living between 50% and 75% and <50% of their lives in fluoridated areas presented a decayed and filled teeth mean ratio of 1.34 (95% CI, 1.02–1.75) and 1.47 (95% CI, 1.05–2.04) higher than those with residential access to fluoridated water >75% of their lifetime, respectively. Longer residential lifetime access to fluoridated water was associated with less dental caries even in a context of multiple exposures to fluoride. [ABSTRACT FROM AUTHOR]

Objectives To examine the short-term impact of fluoridation cessation on children's caries experience measured by tooth surfaces. If there is an adverse short-term effect of cessation, it should be apparent when we focus on smooth tooth surfaces, where fluoride is most likely to have an impact for the age group and time frame considered in this study. Methods We examined data from population-based samples of school children (Grade 2) in two similar cities in the province of Alberta, Canada: Calgary, where cessation occurred in May 2011 and Edmonton where fluoridation remains in place. We analysed change over time (2004/2005 to 2013/2014) in summary data for primary (defs) and permanent ( DMFS) teeth for Calgary and Edmonton, for all tooth surfaces and smooth surfaces only. We also considered, for 2013/2014 only, the exposed subsample defined as lifelong residents who reported usually drinking tap water. Results We observed, across the full sample, an increase in primary tooth decay (mean defs - all surfaces and smooth surfaces) in both cities, but the magnitude of the increase was greater in Calgary (F-cessation) than in Edmonton (F-continued). For permanent tooth decay, when focusing on smooth surfaces among those affected (those with DMFS>0), we observed a non-significant trend towards an increase in Calgary (F-cessation) that was not apparent in Edmonton (F-continued). Conclusions Trends observed for primary teeth were consistent with an adverse effect of fluoridation cessation on children's tooth decay, 2.5-3 years post-cessation. Trends for permanent teeth hinted at early indication of an adverse effect. It is important that future data collection efforts in the two cities be undertaken, to permit continued monitoring of these trends. [ABSTRACT FROM AUTHOR]

Background Control of the world's most important vector-borne viral disease, dengue, is a high priority. A lack of vaccines or effective vector control methods means that novel solutions to disease control are essential. The release of male insects carrying a dominant lethal (RIDL) is one such approach that could be employed to control Aedes aegypti. To maximise the potential of RIDL control, optimum release strategies for transgenic mosquitoes are needed. The use of field data to parameterise models allowing comparisons of the release of different life-stages is presented together with recommendations for effective long-term suppression of a wild Ae. aegypti population. Methods A compartmental, deterministic model was designed and fitted to data from large-scale pupal mark release recapture (MRR) field experiments to determine the dynamics of a pupal release. Pulsed releases of adults, pupae or a combination of the two were simulated. The relative ability of different release methods to suppress a simulated wild population was examined and methods to maintain long-term suppression of a population explored. Results The pupal model produced a good fit to field data from pupal MRR experiments. Simulations using this model indicated that adult-only releases outperform pupal-only or combined releases when releases are frequent. When releases were less frequent pupal-only or combined releases were a more effective method of distributing the insects. The rate at which pupae eclose and emerge from release devices had a large influence on the relative efficacy of pupal releases. The combined release approach allows long-term suppression to be maintained with smaller low-frequency releases than adult- or pupal-only release methods. Conclusions Maximising the public health benefits of RIDL-based vector control will involve optimising all stages of the control programme. The release strategy can profoundly affect the outcome of a control effort. Adult-only, pupal-only and combined releases all have relative advantages in certain situations. This study successfully integrates field data with mathematical models to provide insight into which release strategies are best suited to different scenarios. Recommendations on effective approaches to achieve long-term suppression of a wild population using combined releases of adults and pupae are provided. [ABSTRACT FROM AUTHOR]

Despite highly successful vaccination programs and high vaccine uptake, both endemic pertussis and periodic pertussis outbreaks continue to occur. The under-recognized role of adolescents and adults in disease transmission, due to waning immunity following natural infection and vaccination, and reduced likelihood of correct diagnosis, may contribute to pertussis persistence. We constructed a mathematical model to describe the transmission of pertussis in Southern Ontario in both pre-vaccine and vaccine eras, to estimate the underlying burden of pertussis in the population. The model was well calibrated using the best available data on pertussis in the pre-vaccination (1880–1929) and vaccination (1993–2004) eras in Ontario. Pertussis under-reporting by age group was estimated by comparing model-projected incidence to reported laboratory-confirmed cases for Greater Toronto. Best-fit model estimates gave a basic reproductive number of approximately 10.6, (seasonal range 9.9 to 11.5). Under-reporting increased with age, and approximately >95% of infections in children were caused by infections in persons with waning immunity to pertussis following prior infection or vaccination. A well-calibrated model suggests that under-recognized cases of pertussis in older individuals are likely to be an important driver of ongoing pertussis outbreaks in children. Model projections strongly support enhancement of booster vaccination efforts in adults. [ABSTRACT FROM AUTHOR]

Hazard identification and health risk assessment traditionally rely on results of experimental testing in laboratory animals. It is a lengthy and expensive process, which at the end still involves large uncertainty because the sensitivity of animals is unequal to the sensitivity of humans. The Agency for Toxic Substances and Disease Registry (ATSDR) Computational Toxicology and Method Development Laboratory develops and applies advanced computational models that augment the traditional toxicological approach with multilevel cross-extrapolation techniques. On the one hand, these techniques help to reduce the uncertainty associated with experimental testing, and on the other, they encompass yet untested chemicals, which otherwise would be left out of public health assessment. Computational models also improve understanding of the mode of action of toxic agents, and fundamental mechanisms by which they may cause injury to the people. The improved knowledge is incorporated in scientific health guidance documents of the Agency, including the Toxicological Profiles, which are used as the basis for scientifically defensible public health assessments. [ABSTRACT FROM AUTHOR]