Update of the Blood Lead Reference Value - United States, 2021.

The negative impact of lead exposure on young children and those who become pregnant is well documented but is not well known by those at highest risk from this hazard. Scientific evidence suggests that there is no known safe blood lead level (BLL), because even small amounts of lead can be harmful to a child's developing brain (1). In 2012, CDC introduced the population-based blood lead reference value (BLRV) to identify children exposed to more lead than most other children in the United States. The BLRV should be used as a guide to 1) help determine whether medical or environmental follow-up actions should be initiated for an individual child and 2) prioritize communities with the most need for primary prevention of exposure and evaluate the effectiveness of prevention efforts. The BLRV is based on the 97.5th percentile of the blood lead distribution in U.S. children aged 1-5 years from National Health and Nutrition Examination Survey (NHANES) data. NHANES is a complex, multistage survey designed to provide a nationally representative assessment of health and nutritional status of the noninstitutionalized civilian adult and child populations in the United States (2). The initial BLRV of 5 µg/dL, established in 2012, was based on data from the 2007-2008 and 2009-2010 NHANES cycles. Consistent with recommendations from a former advisory committee, this report updates CDC's BLRV in children to 3.5 µg/dL using NHANES data derived from the 2015-2016 and 2017-2018 cycles and provides helpful information to support adoption by state and local health departments, health care providers (HCPs), clinical laboratories, and others and serves as an opportunity to advance health equity and environmental justice related to preventable lead exposure. CDC recommends that public health and clinical professionals focus screening efforts on populations at high risk based on age of housing and sociodemographic risk factors. Public health and clinical professionals should collaborate to develop screening plans responsive to local conditions using local data. In the absence of such plans, universal BLL testing is recommended. In addition, jurisdictions should follow the Centers for Medicare & Medicaid Services requirement that all Medicaid-enrolled children be tested at ages 12 and 24 months or at age 24-72 months if they have not previously been screened (3).

Cleaning and Disinfectant Chemical Exposures and Temporal Associations with COVID-19 - National Poison Data System, United States, January 1, 2020-March 31, 2020.

On January 19, 2020, the state of Washington reported the first U.S. laboratory-confirmed case of coronavirus disease 2019 (COVID-19) caused by infection with SARS-CoV-2 (1). As of April 19, a total of 720,630 COVID-19 cases and 37,202 associated deaths* had been reported to CDC from all 50 states, the District of Columbia, and four U.S. territories (2). CDC recommends, with precautions, the proper cleaning and disinfection of high-touch surfaces to help mitigate the transmission of SARS-CoV-2 (3). To assess whether there might be a possible association between COVID-19 cleaning recommendations from public health agencies and the media and the number of chemical exposures reported to the National Poison Data System (NPDS), CDC and the American Association of Poison Control Centers surveillance team compared the number of exposures reported for the period January-March 2020 with the number of reports during the same 3-month period in 2018 and 2019. Fifty-five poison centers in the United States provide free, 24-hour professional advice and medical management information regarding exposures to poisons, chemicals, drugs, and medications. Call data from poison centers are uploaded in near real-time to NPDS. During January-March 2020, poison centers received 45,550 exposure calls related to cleaners (28,158) and disinfectants (17,392), representing overall increases of 20.4% and 16.4% from January-March 2019 (37,822) and January-March 2018 (39,122), respectively. Although NPDS data do not provide information showing a definite link between exposures and COVID-19 cleaning efforts, there appears to be a clear temporal association with increased use of these products.

Public Health Responses to COVID-19 Outbreaks on Cruise Ships - Worldwide, February-March 2020.

An estimated 30 million passengers are transported on 272 cruise ships worldwide each year* (1). Cruise ships bring diverse populations into proximity for many days, facilitating transmission of respiratory illness (2). SARS-CoV-2, the virus that causes coronavirus disease (COVID-19) was first identified in Wuhan, China, in December 2019 and has since spread worldwide to at least 187 countries and territories. Widespread COVID-19 transmission on cruise ships has been reported as well (3). Passengers on certain cruise ship voyages might be aged ≥65 years, which places them at greater risk for severe consequences of SARS-CoV-2 infection (4). During February-March 2020, COVID-19 outbreaks associated with three cruise ship voyages have caused more than 800 laboratory-confirmed cases among passengers and crew, including 10 deaths. Transmission occurred across multiple voyages of several ships. This report describes public health responses to COVID-19 outbreaks on these ships. COVID-19 on cruise ships poses a risk for rapid spread of disease, causing outbreaks in a vulnerable population, and aggressive efforts are required to contain spread. All persons should defer all cruise travel worldwide during the COVID-19 pandemic.

A geographic identifier assignment algorithm with Bayesian variable selection to identify neighborhood factors associated with emergency department visit disparities for asthma.

BACKGROUND: Ecologic health studies often rely on outcomes from health service utilization data that are limited by relatively coarse spatial resolutions and missing geographic information, particularly neighborhood level identifiers. When fine-scale geographic data are missing, the ramifications and strategies for addressing them are not well researched or developed. This study illustrates a novel spatio-temporal framework that combines a geographic identifier assignment (i.e., geographic imputation) algorithm with predictive Bayesian variable selection to identify neighborhood factors associated with disparities in emergency department (ED) visits for asthma. METHODS: ED visit records with missing fine-scale spatial identifiers (~ 20%) were geocoded using information from known, coarser, misaligned spatial units using an innovative geographic identifier assignment algorithm. We then employed systematic variable selection in a spatio-temporal Bayesian hierarchical model (BHM) predictive framework within the NIMBLE package in R. Our novel methodology is illustrated in an ecologic case study aimed at identifying neighborhood-level predictors of asthma ED visits in South Carolina, United States, from 1999 to 2015. The health outcome was annual ED visit counts in small areas (i.e., census tracts) with primary diagnoses of asthma (ICD9 codes 493.XX) among children ages 5 to 19 years. RESULTS: We maintained 96% of ED visit records for this analysis. When the algorithm used areal proportions as probabilities for assignment, which addressed differential missingness of census tract identifiers in rural areas, variable selection consistently identified significant neighborhood-level predictors of asthma ED visit risk including pharmacy proximity, average household size, and carbon monoxide interactions. Contrasted with common solutions of removing geographically incomplete records or scaling up analyses, our methodology identified critical differences in parameters estimated, predictors selected, and inferences. We posit that the differences were attributable to improved data resolution, resulting in greater power and less bias. Importantly, without this methodology, we would have inaccurately identified predictors of risk for asthma ED visits, particularly in rural areas. CONCLUSIONS: Our approach innovatively addressed several issues in ecologic health studies, including missing small-area geographic information, multiple correlated neighborhood covariates, and multiscale unmeasured confounding factors. Our methodology could be widely applied to other small-area studies, useful to a range of researchers throughout the world.

Correction to: A geographic identifier assignment algorithm with Bayesian variable selection to identify neighborhood factors associated with emergency department visit disparities for asthma.

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Assessment of an irritant gas plume model for epidemiologic study.

Previously, we reported the development of a Hazard Prediction and Assessment Capability plume dispersion model of the 2005 Graniteville, South Carolina, USA accidental release of chlorine. Here, we assess this model by spatial and statistical comparison with post-incident observed environmental indicators of exposure and other types of observations. Spatial agreement was found when the model was compared to phytotoxic bleaching and corrosion events observed in 2 km radius around the release site. When spatially compared to locations of injured or killed animals, model predictions of the plume footprint were in relatively good agreement. Model-predicted human casualties differed from observed casualty counts primarily due to the shielding effect of buildings. A statistical comparison of observed dog health outcome-derived exposure vs. model predicted exposure showed relatively good agreement, particularly when a subcohort of indoor dogs was excluded. Evaluation and assessment of the building infiltration effect would further improve the model prior to application in epidemiologic study.

Community-based participatory research for the study of air pollution: a review of motivations, approaches, and outcomes.

Neighborhood level air pollution represents a long-standing issue for many communities that, until recently, has been difficult to address due to the cost of equipment and lack of related expertise. Changes in available technology and subsequent increases in community-based participatory research (CBPR) have drastically improved the ability to address this issue. However, much still needs to be learned as these types of studies are expected to increase in the future. To assist, we review the literature in an effort to improve understanding of the motivations, approaches, and outcomes of air monitoring studies that incorporate CBPR and citizen science (CS) principles. We found that the primary motivations for conducting community-based air monitoring were concerns for air pollution health risks, residing near potential pollution sources, urban sprawl, living in "unmonitored" areas, and a general quest for improved air quality knowledge. Studies were mainly conducted using community led partnerships. Fixed site monitoring was primarily used, while mobile, personal, school-based, and occupational sampling approaches were less frequent. Low-cost sensors can enable thorough neighborhood level characterization; however, keeping the community involved at every step, understanding the limitations and benefits of this type of monitoring, recognizing potential areas of debate, and addressing study challenges are vital for achieving harmony between expected and observed study outcomes. Future directions include assessing currently unregulated pollutants, establishing long-term neighborhood monitoring sites, performing saturation studies, evaluating interventions, and creating CS databases.

Photovoice: Assessing the Long-Term Impact of a Disaster on a Community's Quality of Life.

Photovoice is a qualitative method of inquiry whereby individuals can document their lived experiences, particularly individuals whose voices are not typically heard in regard to promoting social change and policy development. We used photovoice to elicit major themes regarding community members' perceptions of the long-term impact on their quality of life as a deadly technological disaster hit a small, rural town in South Carolina. Overall, participants photographed more negative images than positive. Overarching themes included residential and business vacancies, economic decline, the need for clean-up and modernization, attention to wellness or rehabilitation, and concerns for safety. Emergency response agencies should consider the themes elicited from these community residents to help identify where to focus disaster response efforts both in the immediate aftermath and during the long-term recovery period of technological disasters, particularly in underserved, rural communities.

Modeling an irritant gas plume for epidemiologic study.

Plume dispersion modeling systems are often used in assessing human exposures to chemical hazards for epidemiologic study. We modeled the 2005 Graniteville, South Carolina, 54,915 kg railcar chlorine release using both the Areal Locations of Hazardous Atmospheres and Hazard Prediction and Assessment Capability (HPAC) plume modeling systems. We estimated the release rate by an engineering analysis combining semi-quantitative observations and fundamental physical principles. The use of regional meteorological conditions was validated by comparing concentration estimates generated by two source-location weather data-sets. The HPAC model estimated a chlorine plume with 20 ppm outdoor concentrations up to 7 km downwind and 0.25 km upwind/downgrade. A comparative analysis of our two models showed that HPAC was the best candidate for use as a model system on which epidemiologic studies could be based after further model validation. Further validation studies are needed before individual exposure estimates can be reliable and the chlorine plume more definitively modeled.

Off the rails in rural South Carolina: a qualitative study of healthcare provider perspectives on the long-term health impact of the Graniteville train disaster.

INTRODUCTION: In 2005, a train derailment and subsequent chlorine spill ravaged the rural town of Graniteville in South Carolina, resulting in one of the worst chlorine gas exposures in US. HISTORY: Significant health and economic challenges persist in the community more than a decade later. Healthcare providers offered healthcare services to community members in the immediate aftermath of the disaster, and many still live in the community and continue to provide healthcare services. As such, healthcare professionals provide a unique and important perspective to help understand the impact of the disaster on the community's health. The purpose of this study was to explore healthcare providers' perspectives about the long-term effects of the disaster on community health, healthcare access, and wellbeing. METHODS: Semi-structured interviews were conducted with 30 healthcare providers who treated survivors of the Graniteville train disaster. A qualitative, essentialist, inductive thematic analytic approach was used to analyze study data. RESULTS: Four themes emerged regarding the disaster's long-term impact: effects of chlorine exposure on physical health, issues with healthcare access, residual effects of the disaster on personal and community wellbeing, and improving health and community wellbeing. CONCLUSIONS: Disaster recovery should not be considered solely an acute event; agencies must be prepared for long-term, potentially chronic ailments, particularly in underserved, rural communities. Efforts to address the long-term health needs of communities post-disaster should consider the perspectives of healthcare providers to offer a well-rounded assessment of community needs. Study findings can help inform future disaster response strategies in communities locally and globally.

Do corticosteroids reduce the mortality of influenza A (H1N1) infection? A meta-analysis.

INTRODUCTION: Corticosteroids are used empirically in influenza A (H1N1) treatment despite lack of clear evidence for effective treatment. This study aims to assess the efficacy of corticosteroids treatment for H1N1 infection. METHODS: Systematic review and meta-analysis were used to estimate the efficacy of corticosteroids for the prevention of mortality in H1N1 infection. Databases searched included MEDLINE, EMBASE, PubMed, Cochrane Central Register of Controlled Clinical Trials and so on, and bibliographies of retrieved articles, from April 2009 to October 2014. We included both cohort studies and case-control studies reported in English or Chinese that compared treatment effects between corticosteroids and non-corticosteroids therapy in inpatients with H1N1 virus infection. Cohort studies employed mortality as outcome, and case-control studies employed deaths as cases and survivors as controls; both were assessed in this meta-analysis. RESULTS: In total twenty-three eligible studies were included. Both cohort studies (nine studies, n = 1,405) and case-control studies (14 studies, n = 4,700) showed a similar trend toward increased mortality (cohort studies relative risk was 1.85 with 95% confidence interval (CI) 1.46 to 2.33; case-control studies odds ratio was 4.22 with 95% CI 3.10 to 5.76). The results from both subgroup analyses and sensitive analyses were consistent with each other, showing that steroid treatment is associated with mortality. However, considering the fact that corticosteroids were tend to be used in sickest case-patients and heterogeneity was observed between studies, we cannot make a solid conclusion. CONCLUSIONS: Available evidence did not support the use of corticosteroids as standard care for patients with severe influenza. We conclude that further research is required.

Early-life antibiotic use is associated with wheezing among children with high atopic risk: a prospective European study.

BACKGROUND: Little is known about the relationship between antibiotic use and asthma in the children with a higher risk of allergic sensitization. We examine the association between the use of specific therapeutic antibiotics in the first year of life and development of wheezing by 36 months among children with a higher risk of allergic sensitization. METHODS: A multi-center prospective cohort study was conducted among children at high risk for allergic sensitization. A validated questionnaire was used to prospectively collect information on antibiotic use and potential risk factors for wheezing from parents or guardians of 606 children from three European countries at 6, 12, 24 and 36 months of age. Multivariate linear and logistic regression models were used to adjust for potential confounders and effect modifiers and to estimate the association of antibiotic use with the development of early childhood wheezing. RESULTS: Of the antibiotics assessed, only macrolide use in the first year of life was associated with increasing risk for wheezing by 36 months, after adjusting for gender, socioeconomic status, breast feeding >6 months, tobacco smoke exposure, family history of asthma, and respiratory infection (RR = 1.09; 95% CI 1.05-1.13). To avoid a bias by indication, we analyzed children with and without respiratory infection separately. Similar associations were observed for macrolides use in children who had no respiratory infection. CONCLUSIONS: In European children with a familial risk for allergic sensitization, we found a positive association between macrolide use in the first year of life and wheezing until 36 months old which was independent of the effect of respiratory infection.

Dietary supplementation with radionuclide free food improves children's health following community exposure to (137)Cesium: a prospective study.

BACKGROUND: Following the Chernobyl nuclear disaster of 1986, vast areas of Ukraine became contaminated with radionuclides. We examined health effects of school-based food intervention for children in a rural region Narodichi, Ukraine, exposed to low-level radiation through diet of locally produced foods. Until 1995, children received three daily meals with low content of artificial radionuclides which were subsequently reduced to two. METHODS: Annual health screening data (1993-1998) were examined using a quasi-experimental regression discontinuity analysis (n = 947 children; 3,573 repeated measurements). Generalized Estimating Equation models evaluated effect of the food supplementation reduction on hematologic measures and prevalence of anemia, acute respiratory illnesses and diseases of immune system. RESULTS: Prior improvement of several hematologic parameters diminished after food supplementation was reduced. From 1995 to 1996, levels of hemoglobin and erythrocytes decreased from 12.63 (95% CI: 12.56-12.71) to 12.46 g/dL (% CI: 12.39-12.52) and from 4.10 (95% CI: 4.07-4.12) to 4.02 (95% CI: 4.00-4.04) × 10(12)/L, respectively. In agreement, the prevalence ratio (PR) of previously declining anemia increased from 0.57 to 1.31 per year (p(interaction )< .0001). The relation between food supplementation and hemoglobin levels was modified by residential (137)Cs soil levels. After food supply reduction, PR of common cold and bronchitis increased from 1.27 to 2.32 per year (p(interaction) = 0.01) and from 1.09 to 1.24 per year (p(interaction) = 0.43), respectively. CONCLUSIONS: Food supplementation provided by the Ukrainian government likely prevented development of anemia in many of the children residing in the contaminated district. Food supplementation after the community exposure to radioactivity through a diet of locally grown foods should be considered as an effective approach to reduce adverse health effects of radiation.

Effects of long-term low-level radiation exposure after the Chernobyl catastrophe on immunoglobulins in children residing in contaminated areas: prospective and cross-sectional studies.

BACKGROUND: After the Chernobyl nuclear incident in 1986, children in the Narodichesky region, located 80 km west of the Chernobyl Power Plant, were exposed to 137Cesium (137Cs). Little is known about the effects of chronic low-level radiation on humoral immune responses in children residing in contaminated areas. METHODS: In four different approaches we investigated the effect of residential 137Cs exposure on immunoglobulins A, G, M, and specific immunoglobulin E in children. In a dynamic cohort (1993-1998) we included 617 children providing 2,407 repeated measurements; 421 and 523 children in two cross-sectional samples (1997-1998 and 2008-2010, respectively); and 25 participants in a small longitudinal cohort (1997-2010). All medical exams, blood collections, and analyses were conducted by the same team. We used mixed linear models to analyze repeated measurements in cohorts and general linear regression models for cross-sectional studies. RESULTS: Residential soil contamination in 2008 was highly correlated with the individual body burden of 137Cs. Serum IgG and IgM concentrations increased between 1993 and 1998. Children with higher 137Cs soil exposure had lower serum IgG levels, which, however, increased in the small cohort assessed between 1997 and 2010. Children within the fourth quintile of 137Cs soil exposure (266-310 kBq/m2) had higher IgM serum concentrations between 1993 and 1998 but these declined between 1997 and 2010. IgA remained stable with median 137Cs exposures related to higher IgA levels, which was corroborated in the cross-sectional study of 2008-2010. Specific IgE against indoor allergens was detected less often in children with higher 137Cs exposure. CONCLUSIONS: Our findings show radiation-related alterations of immunoglobulins which by themselves do not constitute adverse health effects. Further investigations are necessary to understand how these changes affect health status.

Mercury in fish and adverse reproductive outcomes: results from South Carolina.

BACKGROUND: Mercury is a metal with widespread distribution in aquatic ecosystems and significant neurodevelopmental toxicity in humans. Fish biomonitoring for total mercury has been conducted in South Carolina (SC) since 1976, and consumption advisories have been posted for many SC waterways. However, there is limited information on the potential reproductive impacts of mercury due to recreational or subsistence fish consumption. METHODS: To address this issue, geocoded residential locations for live births from the Vital Statistics Registry (1995-2005, N = 362,625) were linked with spatially interpolated total mercury concentrations in fish to estimate potential mercury exposure from consumption of locally caught fish. Generalized estimating equations were used to test the hypothesis that risk of low birth weight (LBW, <2,500 grams) or preterm birth (PTB, < 37 weeks clinical gestation) was greater among women living in areas with elevated total mercury in fish, after adjustment for confounding. Separate analyses estimated term LBW and PTB risks using residential proximity to rivers with fish consumption advisories to characterize exposure. RESULTS: Term LBW was more likely among women residing in areas in the upper quartile of predicted total mercury in fish (odds ratio [OR] = 1.04; 95% confidence interval [CI]: 1.00-1.09) or within 8 kilometers of a river with a 'do not eat' fish advisory (1.05; 1.00-1.11) compared to the lowest quartile, or rivers without fish consumption restrictions, respectively. When stratified by race, risks for term LBW or PTB were 10-18% more likely among African-American (AA) mothers living in areas with the highest total fish mercury concentrations. CONCLUSIONS: To our knowledge, this is the first study to examine the relationship between fish total mercury concentrations and adverse reproductive outcomes in a large population-based sample that included AA women. The ecologic nature of exposure assessment in this study precludes causal inference. However, the results suggest a need for more detailed investigations to characterize patterns of local fish consumption and potential dose-response relationships between mercury exposure and adverse reproductive outcomes, particularly among AA mothers.