A survey on hydration and use of plastic water bottles among Italian health sector workers.

Background: Modena's Local Health Authority (AUSL) is a public service with more than 5,000 employees. In its facilities, drinking water is available as tap water. However, disposable plastic bottles are also widely used, thus increasing plastic waste. Study design and methods: In the present study, we aimed to investigate employees' drinking habits through an ad hoc 10-item online questionnaire, which was administered in spring 2023. Results: Of the 584 participants (10.8% response rate), 75% of workers reported drinking less than 1.5 liters of water per day. In addition, 74% of workers brought water from home, while 62% used disposable plastic containers bought in the workplace or outside. When asked if they would appreciate a water refilling station in the workplace, whether that would induce them to consume less plastic and to drink more water, 91%, 82%, and 72% of workers said "yes", respectively. By installing water coolers, the estimated mean number of plastic bottles spared every day at the AUSL would be about 6,000. Conclusions: Our data shed light on most employees' perceived need for alternative sources of drinking water, not only in order to drink more for health benefits, but also to reduce plastic usage in favor of reusable, more environmentally friendly materials.

Age-specific prevalence of the different clinical presentations of AD and FTD in young-onset dementia.

BACKGROUND: Studies have shown that the prevalence of all-variants Alzheimer's disease (AD) and frontotemporal dementia (FTD) both increase with age, even before the age of 65. However, it is not known whether their different clinical presentations all increase in prevalence with age in the same way. METHODS: We studied the prevalence of the different clinical presentations of young-onset AD and FTD by 5-year age groups in a population-based study identifying all dementia patients with a diagnosis of AD and FTD and symptoms onset before age 65 in the Modena province, Italy. By using regression models of cumulative occurrences, we also estimated age-specific prevalence and compared the growth curves of the clinical presentations. RESULTS: The prevalence of all-variants AD increased with age, from 18/1,000,000 in the 40-44 age group to 1411/1,000,000 in the 60-64 age group. The prevalence of all-variants FTD also increased with age, from 18/1,000,000 to 866/1,000,000. An estimation of age-specific prevalence functions of each clinical presentation showed that atypical non-amnestic AD and aphasic FTD grew the most in early ages, followed by the behavioural variant of FTD (bvFTD). Then, around the age of 60, amnestic AD took over and its age-specific prevalence continued to increase disproportionally compared to all the other clinical variants of AD and FTD, which, instead, started to decrease in prevalence. CONCLUSIONS: Amnestic AD is the clinical presentation that increases the most with advancing age, followed by bvFTD, suggesting that there is a differential vulnerability to the effect of ageing within the same neurodegenerative disease.

Ozone Treatment for the Management of Caries in Primary Dentition: A Systematic Review of Clinical Studies.

Dental caries in children is a frequent and debilitating condition, whose management is often challenging. The aim of this systematic review was to investigate the effectiveness of ozone applications for the treatment of caries in primary dentition. According to PRISMA guidelines, a systematic literature search was performed up to 6 January 2024. Clinical studies using ozone to treat caries of deciduous teeth were considered for inclusion. Out of the 215 records retrieved, seven studies were eventually included in the review, all of which used gaseous ozone. Four studies were judged at high risk of bias, two at low risk, and one of some concerns. The great heterogeneity of designs, outcomes, and protocols made it impossible to conduct a meta-analysis. Despite some limitations, the evidence yielded by the included studies suggests that ozone application, regardless of the protocol applied, is comparable to other interventions in terms of clinical outcomes and anti-bacterial activity, with no reported adverse effects and good patient acceptance. Therefore, ozone application may be a non-invasive approach to treat caries in primary dentition, especially in very young and poorly cooperative patients. Further standardized and rigorous studies are, however, needed to identify the best clinical protocols for this specific field.

Adverse human health effects of climate change: an update.

Background: The world is currently facing a process of climate change, which may adversely impact human health in many different ways. The safety of food, water and urban environments is endangered by the consequences of climate change. Sea level and temperature rise, along with more frequent and longer heat waves, represent only a few of the effects of climate change. The increased risk of extreme climate events (e.g., cyclones, droughts and floods) is another serious public health issue. These adverse effects are enhanced in areas and countries not having the capacity to effectively deal with climate change. Study design: We primarily aimed at summarizing the impacts of climate change on public health. A further aim was to identify the most concerning consequences of this phenomenon and the vulnerability factors that amplify the negative effects of climate change. Methods: PubMed and other literature databases were used as literature sources for this narrative review based on the search terms 'climate change' and 'diseases categories' up to January 2024, in order to assess the most recent and relevant scientific evidence about the relation between climate change and public health, identify knowledge gaps and priorities for future research. We also screened the websites of major agencies devoted to human health protection and environmental health. Results and Conclusions: Climate change appears to induce a broad spectrum of generally adverse effects on public health. It may increase the risk of infectious diseases, psychiatric disorders, cancer and other diseases. Currently, we are not effectively counteracting this phenomenon, since pollutant and greenhouse gas emissions have been increasing alongside temperatures. A host of measures are required in order to prevent and fight climate change and related health effects. These include the adoption of a holistic approach and the collaboration of different kinds of expertise in order to design more effective strategies. Special attention should be paid to those who live in disadvantaged countries, and those who are more vulnerable to the adverse health consequences of climate change.

Fluoride and caries prevention: a scoping review of public health policies.

Background: Dental caries is the most common infectious disease, affecting approximately 60 to 90% of the world population, especially young children, and disadvantaged communities. Due to the extremely high prevalence and the significant negative impact on general health, well-being, and quality of life it is considered a global public health problem. Despite the improvement of policies to promote oral health care in the past decades, dental caries is still a healthcare challenge, characterized by increasing disparities among different social groups between and within countries. Fluoride-based prevention of dental caries is a cost-effective approach, that has been implemented since 1940's. It includes systemic and topical administrations, through community-based or individual programs. Preventive interventions should be tailored to individual and community caries risk assessment and estimate of cumulative fluoride intake, in order to maximize the preventive effect and avoid the risk of potential adverse effects associated with excessive fluoride exposure. Regulation of public health policies plays a major role in this context. Study design: Scoping review. Methods: The aim of this scoping review was to report an overview of current guidelines regarding fluoride-based preventive strategies for dental caries and relevant policies on the matter, as well as to address current issues related to public health aspects of dental caries prevention. We searched for the relevant literature on the matter, focusing on policy documents, such as recommendations, position papers and guidelines, issued from the major scientific and regulatory institutions involved in oral health promotion and on publications concerning relevant aspects of public health law. Results: Prevention of dental caries through fluoride can rely on topical fluorides for home-use (toothpastes and mouthrinses), professionally applied topical fluorides (gels, varnishes, silver diamine fluoride, fluoride-releasing restorative materials and sealants), fluoride supplements (tablets and drops), and community-based strategies (community water fluoridation, fluoridated salt and milk). Current relevant guidelines for all these preventive aids are outlined in the paper. A significantly greater preventive effect of topical fluorides has been widely established in the recent past, as compared to systemic effects. Furthermore, increasing concerns have emerged on potential adverse effects on general health associated with early and excessive systemic exposure to fluoride, especially for children, supported by recent meta-analyses. Also, community water fluoridation has raised significant aspects of relevance for health law and policies. In a public health perspective, healthcare policymakers should tackle social iniquities by promoting information and oral health literacy, through community and school-based programs, ensuring access to early dental visits and basic dental care and improving availability and affordability of fluoride topical products. Conclusions. Fluoride-based prevention can provide a simple and cost-effective approach to reduce the incidence of dental caries and the associated social burden. Among fluoride-based preventive strategies, systemic community-based administration of fluoride should be considered with great caution, due to the unfavorable risk-benefit ratio currently established. Topical fluoridated pro-ducts are generally preferred, given the optimal risk-benefit ratio. Further efforts must be made to identify and tackle the barriers to dental caries prevention and related social iniquities from a public health perspective. Policies and laws on oral health should promote access to caries prevention with targeted comprehensive strategies.

The key role of public health in renovating Italian biomedical doctoral programs.

Background: A key renovation of doctoral programs is currently ongoing in Italy. Public health and its competencies may play a pivotal role in high-level training to scientific research, including interdisciplinary and methodological abilities. Methods: As a case study, we used the ongoing renovation of the Clinical and Experimental Medicine doctoral program at the University of Modena and Reggio Emilia. We focused on how the program is designed to meet national requirements as well as students' needs, thus improving educational standards for scientific research in the biomedical field, and on the specific contribution of public health and epidemiology in such an effort. Results: The renovation process of doctoral programs in Italy, with specific reference to the biomedical field, focuses on epidemiologic-statistical methodology, ethics, language and communication skills, and open science from an interdisciplinary and international perspective. In the specific context of the doctoral program assessed in the study and from a broader perspective, public health appears to play a key role, taking advantage of most recent methodological advancements, and contributing to the renovation of the learning process and its systematic quality monitoring. Conclusions: From a comparative assessment of this case study and Italian legislation, the key role of public health has emerged in the renovation process of doctoral programs in the biomedical field.

Water fluoridation between public health and public law: an assessment of regulations across countries and their preventive medicine implications.

Background: Among health professionals and health policymakers concern is growing as to the difficulty of balancing the prevention of dental caries through cost-effective interventions and the need to limit unnecessary exposure of the population, and especially children, to environmental chemicals. In this respect, the use of water fluoridation to prevent tooth decay epitomizes the dilemma by raising questions relevant to both public health and public law, ranging from the balance of public health and medical self-determination, the division of powers between local or national authorities over water fluoridation, and the need to avoid the adverse effects of socioeconomic inequalities as well as both under- and over-exposure. Study design: We carried out a narrative review by searching the relevant literature about the laws and rules related to drinking water fluoridation at the community level in the US, UK, and Europe, in order to discuss how the issue is handled from both a public health and public law perspective. Methods: Sources of data for this review were the biomedical and legal literature retrieved by searching online databases, and websites of public health and legal institutions. Results and Conclusions: We found that water fluoridation is still largely adopted throughout the US, while in the UK and particularly in the European Union only a minor part of the population is subject to it. In addition, the recommended and maximum allowed amounts of fluoride in drinking water are being adapted to the public health recommendations and the new regulations, within an evolving evaluation of the epidemiologic evidence and the risk assessment currently in progress by two major regulatory agencies, the US National Toxicology Program - NTP and the European Food Safety Authority - EFSA. Under a comparative public law perspective, the three investigated legislations are facing a reassessment of their policies and regulations, to allow for effective and safe public health measures in the field of water fluoridation and more generally for a preferred use of topical fluoride for caries prevention. A consistent trend across these legislations is the choice to centralize at the national level regulatory and management issues related to water fluoridation, and to carefully balance benefits for dental caries prevention in children and the potential risks of systemic overexposure associated with excess fluoride intake, by promptly responding to the evolving indications by the scientific community and the public health professionals.

Cadmium exposure and cardiovascular disease risk: A systematic review and dose-response meta-analysis.

Exposure to toxic metals is a global public health threat. Among other adverse effects, exposure to the heavy metal cadmium has been associated with greater risk of cardiovascular disease (CVD). Nonetheless, the shape of the association between cadmium exposure and CVD risk is not clear. This systematic review summarizes data on the association between cadmium exposure and risk of CVD using a dose-response approach. We carried out a literature search in PubMed, Web of Science, and Embase from inception to December 30, 2023. Inclusion criteria were: studies on adult populations, assessment of cadmium exposure, risk of overall CVD and main CVD subgroups as endpoints, and observational study design (cohort, cross-sectional, or case-control). We retrieved 26 eligible studies published during 2005-2023, measuring cadmium exposure mainly in urine and whole blood. In a dose-response meta-analysis using the one-stage method within a random-effects model, we observed a positive association between cadmium exposure and risk of overall CVD. When using whole blood cadmium as a biomarker, the association with overall CVD risk was linear, yielding a risk ratio (RR) of 2.58 (95 % confidence interval-CI 1.78-3.74) at 1 µg/L. When using urinary cadmium as a biomarker, the association was linear until 0.5 µg/g creatinine (RR = 2.79, 95 % CI 1.26-6.16), after which risk plateaued. We found similar patterns of association of cadmium exposure with overall CVD mortality and risks of heart failure, coronary heart disease, and overall stroke, whereas for ischemic stroke there was a positive association with mortality only. Overall, our results suggest that cadmium exposure, whether measured in urine or whole blood, is associated with increased CVD risk, further highlighting the importance of reducing environmental pollution from this heavy metal.

Dairy Intake and Risk of Cognitive Decline and Dementia: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies.

Dairy intake may influence cognition through several molecular pathways. However, epidemiologic studies yield inconsistent results, and no dose-response meta-analysis has been conducted yet. Therefore, we performed a systematic review with a dose-response meta-analysis about the association between dairy intake and cognitive decline or incidence of dementia. We investigated prospective studies with a follow-up ≥6 mo on cognitive decline or dementia incidence in adults without known chronic conditions through a systematic search of Embase, Medline, Cochrane Library, Web of Science, and Google Scholar from inception to 11 July 2023. We evaluated the dose-response association using a random-effects model. We identified 15 eligible cohort studies with >300,000 participants and a median follow-up of 11.4 y. We observed a negative nonlinear association between cognitive decline/dementia incidence and dairy intake as assessed through the quantity of consumption, with the nadir at ∼150 g/d (risk ratio: 0.88; 95% confidence interval: 0.78, 0.99). Conversely, we found an almost linear negative association when we considered the frequency of consumption (risk ratio for linear trend: 0.84; 95% confidence interval: 0.77, 0.92 for 1 time/d increase of dairy products). Stratified analysis by dairy products showed different shapes of the association with linear inverse relationship for milk intake, whereas possibly nonlinear for cheese. The inverse association was limited to Asian populations characterized by generally lower intake of dairy products, compared with the null association reported by European studies. In conclusion, our study suggests a nonlinear inverse association between dairy intake and cognitive decline or dementia, also depending on dairy types and population characteristics, although the heterogeneity was still high in overall and several subgroup analyses. Additional studies should be performed on this topic, including a wider range of intake and types of dairy products, to confirm a potential preventing role of dairy intake on cognitive decline and identify ideal intake doses. This review was registered at PROSPERO as CRD42020192395.

Does fluoride exposure affect thyroid function? A systematic review and dose-response meta-analysis.

INTRODUCTION: Fluoride exposure may have various adverse health effects, including affecting thyroid function and disease risk, but the pattern of such relation is still uncertain. METHODS: We systematically searched human studies assessing the relation between fluoride exposure and thyroid function and disease. We compared the highest versus the lowest fluoride category across these studies, and we performed a one-stage dose-response meta-analysis for aggregated data to explore the shape of the association. RESULTS: Most retrieved studies (27 of which with a cross-sectional design) were conducted in Asia and in children, assessing fluoride exposure through its concentrations in drinking water, urine, serum, or dietary intake. Twenty-four studies reported data on thyroid function by measuring thyroid-related hormones in blood (mainly thyroid-stimulating-hormone - TSH), 9 reported data on thyroid disease, and 4 on thyroid volume. By comparing the highest versus the lowest fluoride categories, overall mean TSH difference was 1.05 µIU/mL. Dose-response curve showed no change in TSH concentrations in the lowest water fluoride exposure range, while the hormone levels started to linearly increase around 2.5 mg/L, also dependending on the risk of bias of the included studies. The association between biomarkers of fluoride exposure and TSH was also positive, with little evidence of a threshold. Evidence for an association between fluoride exposure and blood concentrations of thyroid hormones was less evident, though there was an indication of inverse association with triiodothyronine. For thyroid disease, the few available studies suggested a positive association with goiter and with hypothyroidism in both children and adults. CONCLUSIONS: Overall, exposure to high-fluoride drinking water appears to non-linearly affect thyroid function and increase TSH release in children, starting above a threshold of exposure, and to increase the risk of some thyroid diseases.

Greenness and neuropsychiatric symptoms in dementia.

OBJECTIVES: It is acknowledged that living in a green environment may help mental well-being and this may be especially true for vulnerable people. However, the relationship between greenness and neuropsychiatric symptoms in dementia has not been explored yet. METHODS: We collected clinical, neuropsychiatric, and residential data from subjects with dementia living in the province of Modena, Northern Italy. Neuropsychiatric symptoms were measured with the Neuropsychiatry Inventory, a questionnaire administered to the caregiver who assesses the presence and severity of neuropsychiatric symptoms, including delusions, hallucinations, agitation/aggression, dysphoria/depression, anxiety, euphoria/elation, apathy/indifference, disinhibition, irritability/lability, aberrant motor behaviors, sleep disturbances, and appetite/eating changes. Normalized Difference Vegetation Index (NDVI) was used as a proxy of greenness. Regression models were constructed to study the association between greenness and neuropsychiatric features. RESULTS: 155 patients with dementia were recruited. We found that greenness is variably associated with the risk of having neuropsychiatric symptoms. The risk of apathy was lower with lower levels of greenness (OR = 0.42, 95% CI 0.19-0.91 for NDVI below the median value). The risk of psychosis was higher with lower levels of greenness but with more imprecise values (OR = 1.77, 95% CI 0.84-3.73 for NDVI below the median value). CONCLUSION: Our results suggest a possible association between greenness and neuropsychiatric symptoms in people with dementia. If replicated in larger samples, these findings will pave the road for identifying innovative greening strategies and interventions that can improve mental health in dementia.

Nonchromosomal birth defects and risk of childhood acute leukemia: An assessment in 15 000 leukemia cases and 46 000 controls from the Childhood Cancer and Leukemia International Consortium.

Although recent studies have demonstrated associations between nonchromosomal birth defects and several pediatric cancers, less is known about their role on childhood leukemia susceptibility. Using data from the Childhood Cancer and Leukemia International Consortium, we evaluated associations between nonchromosomal birth defects and childhood leukemia. Pooling consortium data from 18 questionnaire-based and three registry-based case-control studies across 13 countries, we used multivariable logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between a spectrum of birth defects and leukemia. Our analyses included acute lymphoblastic leukemia (ALL, n = 13 115) and acute myeloid leukemia (AML, n = 2120) cases, along with 46 172 controls. We used the false discovery rate to account for multiple comparisons. In the questionnaire-based studies, the prevalence of birth defects was 5% among cases vs 4% in controls, whereas, in the registry-based studies, the prevalence was 11% among cases vs 7% in controls. In pooled adjusted analyses, there were several notable associations, including (1) digestive system defects and ALL (OR = 2.70, 95% CI: 1.46-4.98); (2) congenital anomalies of the heart and circulatory system and AML (OR = 2.86, 95% CI: 1.81-4.52) and (3) nervous system defects and AML (OR = 4.23, 95% CI: 1.50-11.89). Effect sizes were generally larger in registry-based studies. Overall, our results could point to novel genetic and environmental factors associated with birth defects that could also increase leukemia susceptibility. Additionally, differences between questionnaire- and registry-based studies point to the importance of complementary sources of birth defect phenotype data when exploring these associations.

Residential exposure to magnetic fields from transformer stations and risk of childhood leukemia.

BACKGROUND: Several studies have documented an increased risk of leukemia among children exposed to magnetic fields from high-voltage power lines, with some evidence of dose-response relation. However, findings in some studies have been inconsistent, and data on the effects of different sources of exposure are lacking. In this study, we evaluated the relation of childhood leukemia risk to exposure to magnetic fields from transformer stations. METHODS: We conducted a population-based case-control study in a pediatric population of two Northern Italian provinces of Modena and Reggio Emilia. We included 182 registry-identified childhood leukemia cases diagnosed during 1998-2019 and 726 population controls matched on sex, year of birth, and province of residence. We assessed exposure by calculating distance from childhood residence to the nearest transformer station within a geographical information system, computing disease odds ratios (ORs) and 95% confidence intervals (CIs) using conditional logistic regression, adjusting for potential confounders. We evaluated exposure using two buffers (15 m and 25 m radius) and assessed two case groups: leukemia (all subtypes) and acute lymphoblastic leukemia (ALL). RESULTS: Residing within 15 m of a transformer station (vs. ≥15 m) was not appreciably associated with risk of leukemia (all subtypes) or ALL. We found similar results using a less stringent exposure buffer (25 m). Among children aged ≥5 years, the adjusted ORs were 1.3 (95% CI 0.1-12.8) for leukemia and 1.3 (95% CI 0.1-12.4) for ALL using the 15 m buffer, while they were 1.7 (95% CI 0.4-7.0) for leukemia and 0.6 (95% CI 0.1-4.8) for ALL using the 25 m buffer. CONCLUSIONS: While we found no overall association between residential proximity to transformer stations and childhood leukemia, there was some evidence for elevated risk of childhood leukemia among children aged ≥5 years. Precision was limited by the low numbers of exposed children.

Adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet and exposure to selenium species: A cross-sectional study.

Selenium is a trace element found in many chemical forms. Selenium and its species have nutritional and toxicologic properties, some of which may play a role in the etiology of neurological disease. We hypothesized that adherence to the Mediterranean-Dietary Approach to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) diet could influence intake and endogenous concentrations of selenium and selenium species, thus contributing to the beneficial effects of this dietary pattern. We carried out a cross-sectional study of 137 non-smoking blood donors (75 females and 62 males) from the Reggio Emilia province, Northern Italy. We assessed MIND diet adherence using a semiquantitative food frequency questionnaire. We assessed selenium exposure through dietary intake and measurement of urinary and serum concentrations, including speciation of selenium compound in serum. We fitted non-linear spline-based regression models to investigate the association between MIND diet adherence and selenium exposure concentrations. Adherence to the MIND diet was positively associated with dietary selenium intake and urinary selenium excretion, whereas it was inversely associated with serum concentrations of overall selenium and organic selenium, including serum selenoprotein P-bound selenium, the most abundant circulating chemical form of the metalloid. MIND diet adherence also showed an inverted U-shaped relation with inorganic selenium and particularly with its hexavalent form, selenate. Our results suggest that greater adherence to the MIND diet is non-linearly associated with lower circulating concentrations of selenium and of 2 potentially neurotoxic species of this element, selenoprotein P and selenate. This may explain why adherence to the MIND dietary pattern may reduce cognitive decline.

Involuntary Hospitalizations in an Italian Acute Psychiatric Ward: A 6-Year Retrospective Analysis.

Purpose: We evaluated the differences between demographic (age, sex, nationality, employment, housing, schooling, support administrator), clinical (hospitalization reason, aggressive behaviour, length of hospitalization, psychiatric diagnosis and comorbidities, psychiatric medications, discharge destination, "revolving door" hospitalizations) and environmental (pre-and pandemic period) variables in voluntary (VHs) and involuntary hospitalizations (IHs) in an acute psychiatric ward during a 6-year period. Patients and Methods: We retrospectively collected the selected variables concerning the hospitalizations of subjects over 18 years of age in the Service for Psychiatric Diagnosis and Care of Mental Health and Drug Abuse Department in Modena from 01/01/2017 to 31/12/2022. Results: We observed a progressive and sharp reduction in the number of VHs (n = 1800; 61.41%) during the pandemic and a stability of IHs (n = 1131; 38.59%), which in 2022 became prevalent. We highlighted the following differences between VHs and IHs: an increase in hospitalization length in IHs (14.25 mean days ± 15.89 SD) in comparison with VHs (8.78 mean days ± 13.88 SD), which increased more during the pandemic; an increase in aggressive behavior in IHs, especially during the pandemic (Pearson Chi2 = 90.80; p = 0.000); a prevalence of schizophrenia and bipolar disorders (Pearson Chi2 = 283.63; p = 0.000) and more frequent maladaptive social conditions among subjects in IHs. Conclusion: During the 6-year observation period, we underscored a trend of increasingly reduced recourse to VHs, whereas IHs increased even in the pandemic. Our results suggest that IHs in Psychiatry represented an extreme measure for treating the most severe psychopathological situations such as schizophrenia and bipolar disorders, characterized by aggressive behaviour and precarious social conditions, which needed longer stay than VHs, especially during the pandemic.

Health surveillance for SARS-CoV-2: infection spread and vaccination coverage in the schools of Modena province, Italy.

Introduction: In Italy, over 4.8 million individuals aged 0-19 years have been infected with SARS-CoV-2. This study aims to evaluate the spread of SARS-CoV-2 within schools in Modena province and the influence of anti-SARS-CoV-2 vaccination coverage. Methods: We performed a survey in the period 1 September-15 December 2021, involving student population aged 0-19 years and related teachers screened for SARS-CoV-2 infection using nasopharyngeal swab after the detection of an index case within their class. During the study period, vaccination against SARS-CoV-2 was actively offered to all subjects aged ≥12 years. Results: A total of 13,934 subjects were tested, 12,534 students and 1,400 teachers (594 classes). We identified a total of 594 and 779 index and secondary cases, respectively. We found that 9.8% of students and 10.6% of teachers were positive for SARS-CoV-2. Overall at the test time, 32.5% were vaccinated with at least one dose of anti-SARS-CoV-2 vaccine. Among secondary cases, 7.8% were vaccinated compared to 34.9% among negative tested subjects. A higher secondary attack rate was for non-vaccinated subjects rather than vaccinated ones (8.1% vs. 1.4%). Higher secondary attack rates were reported for subjects attending infant and primary school (5.9 and 9.6%, respectively). Lower secondary attack rates were for those who attended middle school (4.9%) and especially high school (1.7%). Conclusion: Our results highlight the differential spread of the infection within various educational settings and that the vaccination, available in the study period for the population aged ≥12, have mitigated SARS-CoV-2 spread in high and middle schools.

Fluoride Exposure and Skeletal Fluorosis: a Systematic Review and Dose-response Meta-analysis.

PURPOSE OF REVIEW: We performed a systematic review and meta-analysis on the relation between fluoride exposure and skeletal fluorosis (SF) using a novel statistical methodology for dose-response modeling. RECENT FINDINGS: Skeletal fluorosis, a major health issue that is endemic in some regions, affects millions of people worldwide. However, data regarding the dose-response relation between fluoride exposure and SF are limited and outdated. We included twenty-three studies in the meta-analysis. When comparing the highest versus the lowest fluoride category, the summary risk ratio (RR) for SF prevalence was 2.05 (95% CI 1.60; 2.64), with a value of 2.73 (95% CI 1.92; 3.90) for drinking water and 1.40 (95% CI 0.90; 2.17) for urinary fluoride. The RR by the risk of bias (RoB) was 2.37 (95% CI 1.56; 3.58) and 1.78 (95% CI 1.34; 2.36) for moderate and high RoB studies, respectively. The dose-response curve based on a one-stage cubic spline regression model showed an almost linear positive relation between exposure and SF occurrence starting from relatively low concentrations up to 5 mg/L and 2.5 mg/L, respectively, for water and urinary fluoride, with no substantial increase above this threshold. The RR for developing moderate-severe forms increases at 5.00 mg/L and 2.5 mg/L of water and urinary fluoride, respectively. Better-quality studies are needed to confirm these results, but greater attention should be given to water fluoride levels to prevent SF, in addition to the other potential adverse effects of fluoride exposure.

GRADE GUIDANCE 38: Updated guidance for rating up certainty of evidence due to a dose-response gradient.

INTRODUCTION: This updated guidance from the Grading of Recommendations Assessment, Development, and Evaluation addresses rating up certainty of evidence due to a dose-response gradient (DRG) observed in synthesis of intervention and exposure studies. STUDY DESIGN AND SETTING: This guidance was developed using iterative discussions and consensus in multiple meetings and was presented to attendees of the Grading of Recommendations Assessment, Development, and Evaluation Working Group meeting for feedback in November 2022 and for final approval in May 2023. RESULTS: The guidance consists of two steps. The first is to determine whether the DRG is credible. We describe five items for assessing credibility: a) is DRG identified using a proper analytical approach; b) is confounding the cause of the DRG; c) is there serious concern about ecological bias; d) is the DRG consistent across studies; and e) is there indirect evidence supporting the DRG. The first two of these items are the most critical. If the DRG was judged to be credible, then the second step is to apply the DRG domain and consider rating up, but only by one level due to the concern about residual confounding. CONCLUSION: Systematic review authors should only rate up certainty in evidence when a DRG is deemed credible.