Last data update: Nov 11, 2024. (Total: 48109 publications since 2009)
Records 1-30 (of 48 Records) |
Query Trace: Nett RJ[original query] |
---|
A scoping review to determine if adverse human health effects are associated with use of organophosphates for mosquito control
Tai Z , Connelly CR , Kuczynski Lange S , Foley N , De Leon Rivera J , Lozano S , Nett RJ . J Med Entomol 2024 Organophosphate insecticides are widely used for adult mosquito control. Although proven effective in reducing mosquito populations and limiting arbovirus transmission, public concern exists regarding potential human health effects associated with organophosphate exposure. The aim of this scoping review was to describe any reported human health conditions associated with organophosphates during their use for adult mosquito control in the United States and Canada. Original peer-reviewed articles published in English language journals from 1 January 2000 to 22 May 2024, were obtained by searching from the databases MEDLINE, EMBASE, Agricultural & Environmental Science Collection, CAB Abstracts, and Scopus. The search identified 6,154 screened articles. Following an independent review, 10 studies were identified that described human health conditions associated with organophosphate exposure during adult mosquito control applications. Of the 10 included studies, only two articles were published within the last 11 years (2013 to 22 May 2024). Three types of study design were represented in the included studies: cohort (n = 5), case study (n = 1), and risk assessment (n = 4). The included studies could not determine causality between exposure to adulticides and development of illness or adverse impacts. Exposure to organophosphates did not contribute to an observed increase in metabolic toxicity, hospitalization rates, or self-reported symptoms and exposure. The available and limited evidence indicates that organophosphates can be used safely to control nuisance mosquitoes or mosquitoes that transmit arboviruses. Continued research regarding the human health effects associated with organophosphate applications for adult mosquito control could help evaluate the basis of the public's concerns and inform public health decision-making. |
Multi-model prediction of West Nile virus neuroinvasive disease with machine learning for identification of important regional climatic drivers
Holcomb KM , Staples JE , Nett RJ , Beard CB , Petersen LR , Benjamin SG , Green BW , Jones H , Johansson MA . Geohealth 2023 7 (11) e2023GH000906 West Nile virus (WNV) is the leading cause of mosquito-borne illness in the continental United States (CONUS). Spatial heterogeneity in historical incidence, environmental factors, and complex ecology make prediction of spatiotemporal variation in WNV transmission challenging. Machine learning provides promising tools for identification of important variables in such situations. To predict annual WNV neuroinvasive disease (WNND) cases in CONUS (2015-2021), we fitted 10 probabilistic models with variation in complexity from naïve to machine learning algorithm and an ensemble. We made predictions in each of nine climate regions on a hexagonal grid and evaluated each model's predictive accuracy. Using the machine learning models (random forest and neural network), we identified the relative importance and variation in ranking of predictors (historical WNND cases, climate anomalies, human demographics, and land use) across regions. We found that historical WNND cases and population density were among the most important factors while anomalies in temperature and precipitation often had relatively low importance. While the relative performance of each model varied across climatic regions, the magnitude of difference between models was small. All models except the naïve model had non-significant differences in performance relative to the baseline model (negative binomial model fit per hexagon). No model, including the ensemble or more complex machine learning models, outperformed models based on historical case counts on the hexagon or region level; these models are good forecasting benchmarks. Further work is needed to assess if predictive capacity can be improved beyond that of these historical baselines. |
Impact of Epidemic Intelligence Service training in occupational respiratory epidemiology
Tomasi SE , Fechter-Leggett ED , Materna BL , Meiman JG , Nett RJ , Cummings KJ . ATS Sch 2023 4 (4) [Epub ahead of print] The Centers for Disease Control and Prevention's Epidemic Intelligence Service (EIS)is a fellowship in applied epidemiology for physicians, veterinarians, nurses, scientists, and other health professionals. Each EIS fellow is assigned to a position at a federal, state, or local site for 2 years of on-the-job training in outbreak investigation, epidemiologic research, surveillance system evaluation, and scientific communication. Although the original focus of the program on the control of infectious diseases remains salient, positions are available for training in other areas of public health, including occupational respiratory disease. In this Perspective, we describe the EIS program, highlight three positions (one federal and two state-based) that provide training in occupational respiratory epidemiology, and summarize trainees' experiences in these positions over a30-year period. For early-career health professionals interested in understanding and preventing occupational respiratory hazards and diseases, EIS offers a unique career development opportunity. |
Eye and airway symptoms in hospital staff exposed to a product containing hydrogen peroxide, peracetic acid, and acetic acid
Blackley BH , Nett RJ , Cox-Ganser JM , Harvey RR , Virji MA . Am J Ind Med 2023 66 (8) 655-669 BACKGROUND: Sporicidal products containing hydrogen peroxide (HP), peracetic acid (PAA), and acetic acid (AA) are used widely in multiple industries, including healthcare. Despite widespread use in healthcare, few studies have assessed associations between exposures to HP, PAA, and AA, and work-related symptoms in these settings. METHODS: In 2018, we performed a health and exposure assessment at a hospital where a sporicidal product consisting of HP, PAA, and AA, was used as the primary cleaner on hospital surfaces. We collected 56 personal and mobile air samples for HP, PAA, and AA on participants while they performed their regular cleaning duties; collected area samples for HP (n = 28), PAA (n = 28), and AA (n = 70) in multiple hospital locations where cleaning was performed; and administered a postshift survey to assess eye, skin, and upper and lower airway symptoms that occurred cross-shift or in the previous 4 weeks. RESULTS: Full-shift exposure levels for HP (range: <3-559 ppb), PAA (range: <0.2-8 ppb), and AA (range: <5-915 ppb) were all below US occupational exposure limits. We observed positive associations (p < 0.05) between shift, departmental average, and departmental 95th percentile exposures to HP, PAA, and AA vapors, and work-related acute (cross-shift) and chronic (previous 4 weeks) eye, upper airway, and lower airway symptoms after adjusting for age, gender, smoking status, use of other cleaning products containing sensitizers and irritants, allergic status, and stress. CONCLUSIONS: Our observations of work-related upper and lower airway symptoms among hospital workers exposed to vapors from a sporicidal product containing HP, PAA, and AA indicate a need for a combination of engineering, administrative, and PPE controls to reduce exposure. Additionally, alternative nonchemical disinfection technologies should be further investigated as a means to simultaneously reduce healthcare workers' exposure to disinfectants while also minimizing costly healthcare-acquired infections. |
Storage of euthanasia solution as a factor in addressing veterinarian suicides
Nett RJ , Witte TK , Tomasi SE , Fowler KA . J Am Vet Med Assoc 2020 256 (12) 1321-1322 In a recent study of suicides and deaths of uncertain intent among US veterinary professionals, Witte et al1 found that for 34 of 73 (47%) veterinarians, the mechanism of death was classified as poisoning, with 18 of those 34 deaths (or 25% of the total) attributed to pentobarbital, the active ingredient in euthanasia solutions. Even more troubling, for 13 of the 18 deaths attributed to pentobarbital poisoning, the death-related injury occurred at home. Although data were not available on where or how the pentobarbital was procured, it seems likely that in some, if not all, of these cases, euthanasia solution was removed from a clinic setting or shipped directly to a decedent’s home office and used for the purpose of suicide. |
Letters to the Editor
Tomasi SE , Fechter-Leggett ED , Edwards NT , Nett RJ , Reddish AD , Crosby AE . J Am Vet Med Assoc 2019 254 (5) 579-580 The authors thank Dr. Parker for his letter regarding our recent study on suicide mortality among US veterinarians. Regarding Dr. Parker’s comment about future studies to compare suicide among professional groups, previous studies have shown variability in suicide rates by occupation, especially in the health-care professions, and by sex. In some studies, suicide rates for veterinarians and select other health-care professionals, such as dentists, are high, but in other studies, they are not.1 |
Combating West Nile virus disease - time to revisit vaccination
Gould CV , Staples JE , Huang CY , Brault AC , Nett RJ . N Engl J Med 2023 388 (18) 1633-1636 It is time to revisit the need for human West Nile virus (WNV) vaccines. Since its initial detection in the United States in 1999, WNV has become the leading cause of domestic arthropod-borne viral (arboviral) disease. Spread by infected culex-species mosquitoes, WNV has caused more than 55,000 reported cases of human disease, more than 27,000 of them neuroinvasive, and 2600 deaths between 1999 and 2021, according to data from the Centers for Disease Control and Prevention (CDC). WNV is also an ongoing public health threat in many areas of the world; the largest recorded outbreak in Europe occurred in 2018. |
All causes of death among veterinarians in the United States during 1979 through 2015
Tomasi SE , Fechter-Leggett ED , Edwards NT , Reddish AD , Nett RJ . J Am Vet Med Assoc 2022 260 (9) 1-10 OBJECTIVE: To assess proportionate mortality from all causes for male and female US veterinarians during 1979 through 2015. SAMPLE: Death records for 11,620 veterinarians. PROCEDURES: For this proportionate mortality ratio (PMR) study, information for veterinarians who died during 1979 through 2015 was obtained from AVMA obituary and life insurance databases and submitted to a centralized database of US death records to obtain underlying causes of death. Decedent data that met records-matching criteria were imported into a software program for calculation of PMRs for all causes stratified by sex and indirectly standardized for age, race, and 5-year calendar period with 95% CIs. RESULTS: 11,620 decedents consisted of 11,049 (95%) males and 571 (5%) females with a median age at death of 77 years. Proportionate mortality for all veterinarian decedents was higher than expected for melanoma (PMRs, 2.1 and 2.2 for males and females, respectively), suicide (PMRs, 2.1 and 3.5 for males and females, respectively), and transportation injuries (PMRs, 1.7 and 1.6 for males and females, respectively). Proportionate mortality for all decedents was lower than expected for respiratory cancers (PMRs, 0.6 and 0.5 for males and females, respectively), diabetes mellitus (PMRs, 0.7 and 0.4 for males and females, respectively), heart disease (PMRs, 0.9 and 0.6 for males and females, respectively), and respiratory disorders (PMRs, 0.7 and 0.6 for males and females, respectively). CLINICAL RELEVANCE: Results indicated proportionate mortality from malignant melanoma, transportation injuries, and suicide for male and female veterinarians was higher than the general population. These data may help stakeholders improve veterinarian workplace safety and health guidelines. |
Evaluation of an open forecasting challenge to assess skill of West Nile virus neuroinvasive disease prediction.
Holcomb KM , Mathis S , Staples JE , Fischer M , Barker CM , Beard CB , Nett RJ , Keyel AC , Marcantonio M , Childs ML , Gorris ME , Rochlin I , Hamins-Puértolas M , Ray EL , Uelmen JA , DeFelice N , Freedman AS , Hollingsworth BD , Das P , Osthus D , Humphreys JM , Nova N , Mordecai EA , Cohnstaedt LW , Kirk D , Kramer LD , Harris MJ , Kain MP , Reed EMX , Johansson MA . Parasit Vectors 2023 16 (1) 11 BACKGROUND: West Nile virus (WNV) is the leading cause of mosquito-borne illness in the continental USA. WNV occurrence has high spatiotemporal variation, and current approaches to targeted control of the virus are limited, making forecasting a public health priority. However, little research has been done to compare strengths and weaknesses of WNV disease forecasting approaches on the national scale. We used forecasts submitted to the 2020 WNV Forecasting Challenge, an open challenge organized by the Centers for Disease Control and Prevention, to assess the status of WNV neuroinvasive disease (WNND) prediction and identify avenues for improvement. METHODS: We performed a multi-model comparative assessment of probabilistic forecasts submitted by 15 teams for annual WNND cases in US counties for 2020 and assessed forecast accuracy, calibration, and discriminatory power. In the evaluation, we included forecasts produced by comparison models of varying complexity as benchmarks of forecast performance. We also used regression analysis to identify modeling approaches and contextual factors that were associated with forecast skill. RESULTS: Simple models based on historical WNND cases generally scored better than more complex models and combined higher discriminatory power with better calibration of uncertainty. Forecast skill improved across updated forecast submissions submitted during the 2020 season. Among models using additional data, inclusion of climate or human demographic data was associated with higher skill, while inclusion of mosquito or land use data was associated with lower skill. We also identified population size, extreme minimum winter temperature, and interannual variation in WNND cases as county-level characteristics associated with variation in forecast skill. CONCLUSIONS: Historical WNND cases were strong predictors of future cases with minimal increase in skill achieved by models that included other factors. Although opportunities might exist to specifically improve predictions for areas with large populations and low or high winter temperatures, areas with high case-count variability are intrinsically more difficult to predict. Also, the prediction of outbreaks, which are outliers relative to typical case numbers, remains difficult. Further improvements to prediction could be obtained with improved calibration of forecast uncertainty and access to real-time data streams (e.g. current weather and preliminary human cases). |
The Impact of Community-Based Testing Sites and Gift Incentives on COVID-19 Testing Uptake in Maryland, April 29 - May 9, 2021.
Turbyfill C , Thomas I , Agravat N , Prasher JM , Nett RJ , Stevens M , Ricaldi JN , Dunams TM , Brickhouse-Frazier L , Carter MD , Gebru Y , King A , May CS , Miller JD , Oguh C , Pullman A , Roman K , Rose C , Scherr R , Sidibe T , Soelaeman R , Weinstein J , Wilson T , Tran CH . Am J Health Promot 2022 37 (2) 8901171221119796 PURPOSE: Information on incentives for COVID-19 testing is needed to understand effective practices that encourage testing uptake. We describe characteristics of those who received an incentive after performing a rapid antigen test. DESIGN: Cross-sectional descriptive analysis of survey data. SETTING: During April 29-May 9, 2021, COVID-19 rapid antigen testing was offered in 2 Maryland cities. SAMPLE: Convenience sample of 553 adults (≥18 years) who tested and received an incentive; 93% consented to survey. MEASURES: Survey questions assessed reasons for testing, testing history, barriers, and demographics. ANALYSIS: Robust Poisson regressions were used to determine characteristic differences based on testing history and between participants who would re-test in the future without an incentive vs participants who would not. RESULTS: The most common reasons for testing were the desire to be tested (n = 280; 54%) and convenience of location (n = 146; 28%). Those motivated by an incentive to test (n = 110; 21%) were 5.83 times as likely to state they would not test again without an incentive, compared to those with other reasons for testing (95% CI: 2.67-12.72, P < .001). CRITICAL LIMITATIONS: No comparative study group. CONCLUSION: Results indicate internal motivation and convenience were prominent factors supporting testing uptake. Incentives may increase community testing participation, particularly among people who have never tested. Keywords COVID-19, pandemic, incentives, health behavior, community testing. |
Influenza-Like Illness Among Personnel Responding to U.S. Quarantine of Cruise Ship Passengers Exposed to SARS-CoV-2.
Harvey RR , Nett RJ , McNamara K , McClung RP , Pieracci EG , Mayer O , Labar KA , Xu K , Facey J , Honein MA . J Occup Environ Med 2021 64 (1) 58-63 OBJECTIVES: Before community transmission of COVID-19 was recognized in the United States, cruise ship passengers with high risk for exposure to SARS-CoV-2 were repatriated and quarantined. We describe cases of influenza-like illness (ILI) among responders. METHODS: We reviewed situation reports and responder illness reports to characterize ill responders, including illness onset date, symptoms, fever, diagnostic tests, potential breaches in PPE use, and return to work status. RESULTS: Among 339 responders, nine (3%) reported ILI. No breaches in PPE were reported. Three responders with ILI were tested for both SARS-CoV-2 infection and influenza A; none tested positive for SARS-CoV-2 infection and two tested positive for influenza A. CONCLUSIONS: Despite an outbreak of ILI among responders, none were diagnosed with COVID-19, suggesting preventive measures in place might have been sufficient to prevent responders from SARS-CoV-2 exposure. |
Occupational Histoplasmosis: Epidemiology and Prevention Measures
de Perio MA , Benedict K , Williams SL , Niemeier-Walsh C , Green BJ , Coffey C , Di Giuseppe M , Toda M , Park JH , Bailey RL , Nett RJ . J Fungi (Basel) 2021 7 (7) In areas where Histoplasma is endemic in the environment, occupations involving activities exposing workers to soil that contains bird or bat droppings may pose a risk for histoplasmosis. Occupational exposures are frequently implicated in histoplasmosis outbreaks. In this paper, we review the literature on occupationally acquired histoplasmosis. We describe the epidemiology, occupational risk factors, and prevention measures according to the hierarchy of controls. |
Observed Face Mask Use at Six Universities - United States, September-November 2020.
Barrios LC , Riggs MA , Green RF , Czarnik M , Nett RJ , Staples JE , Welton MD , Muilenburg JL , Zullig KJ , Gibson-Young L , Perkins AV , Prins C , Lauzardo M , Shapiro J , Asimellis G , Kilgore-Bowling G , Ortiz-Jurado K , Gutilla MJ . MMWR Morb Mortal Wkly Rep 2021 70 (6) 208-211 Approximately 41% of adults aged 18-24 years in the United States are enrolled in a college or university (1). Wearing a face mask can reduce transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19) (2), and many colleges and universities mandate mask use in public locations and outdoors when within six feet of others. Studies based on self-report have described mask use ranging from 69.1% to 86.1% among adults aged 18-29 years (3); however, more objective measures are needed. Direct observation by trained observers is the accepted standard for monitoring behaviors such as hand hygiene (4). In this investigation, direct observation was used to estimate the proportion of persons wearing masks and the proportion of persons wearing masks correctly (i.e., covering the nose and mouth and secured under the chin*) on campus and at nearby off-campus locations at six rural and suburban universities with mask mandates in the southern and western United States. Trained student observers recorded mask use for up to 8 weeks from fixed sites on campus and nearby. Among 17,200 observed persons, 85.5% wore masks, with 89.7% of those persons wearing the mask correctly (overall correct mask use: 76.7%). Among persons observed indoors, 91.7% wore masks correctly. The proportion correctly wearing masks indoors varied by mask type, from 96.8% for N95-type masks and 92.2% for cloth masks to 78.9% for bandanas, scarves, and similar face coverings. Observed indoor mask use was high at these six universities with mask mandates. Colleges and universities can use direct observation findings to tailor training and messaging toward increasing correct mask use. |
Occupational respiratory and skin diseases among workers exposed to metalworking fluids
Nett RJ , Stanton M , Grimes GR . Curr Opin Allergy Clin Immunol 2020 Publish Ahead of Print (2) 121-127 PURPOSE OF REVIEW: To examine respiratory and skin diseases that occur among workers exposed to metalworking fluids (MWFs) used during machining processes. RECENT FINDINGS: Five cases of a severe and previously unrecognized lung disease characterized by B-cell bronchiolitis and alveolar ductitis with emphysema (BADE) were identified among workers at a machining facility that used MWFs, although MWF exposure could not be confirmed as the etiology. In the United Kingdom, MWF is now the predominant cause of occupational hypersensitivity pneumonitis (HP). Under continuous conditions associated with respiratory disease outbreaks, over a working lifetime of 45 years, workers exposed to MWF at 0.1 mg/m3 are estimated to have a 45.3% risk of acquiring HP or occupational asthma under outbreak conditions and a 3.0% risk assuming outbreak conditions exist in 5% of MWF environments. In addition to respiratory outcomes, skin diseases such as allergic and irritant contact dermatitis persist as frequent causes of occupational disease following MWF exposure. SUMMARY: Healthcare providers need to consider MWF exposure as a potential cause for work-related respiratory and skin diseases. Additional work is necessary to more definitively characterize any potential association between MWF exposures and BADE. Medical surveillance should be implemented for workers regularly exposed to MWF. |
Occupational bronchiolitis: An update
Nett RJ , Harvey RR , Cummings KJ . Clin Chest Med 2020 41 (4) 661-686 Occupational bronchiolitis is characterized by inflammation of the small airways, and represents a heterogeneous set of lung conditions that can occur following a range of inhalation exposures related to work. The most common clinical presentation includes insidious onset of exertional dyspnea and cough. Multiple reports in recent years have drawn attention to previously unrecognized risk factors for occupational bronchiolitis following exposures in several settings. Both current and past occupational exposures, including prior military deployment-related exposures, should be considered in patients undergoing evaluation for unexplained dyspnea. Diagnostic testing for potential bronchiolitis should include a thorough assessment of the small airways. |
Exposures and emissions in coffee roasting facilities and cafes: diacetyl, 2,3-pentanedione, and other volatile organic compounds
LeBouf RF , Blackley BH , Fortner AR , Stanton M , Martin SB , Groth CP , McClelland TL , Duling MG , Burns DA , Ranpara A , Edwards N , Fedan KB , Bailey RL , Cummings KJ , Nett RJ , Cox-Ganser JM , Virji MA . Front Public Health 2020 8 561740 Roasted coffee and many coffee flavorings emit volatile organic compounds (VOCs) including diacetyl and 2,3-pentanedione. Exposures to VOCs during roasting, packaging, grinding, and flavoring coffee can negatively impact the respiratory health of workers. Inhalational exposures to diacetyl and 2,3-pentanedione can cause obliterative bronchiolitis. This study summarizes exposures to and emissions of VOCs in 17 coffee roasting and packaging facilities that included 10 cafés. We collected 415 personal and 760 area full-shift, and 606 personal task-based air samples for diacetyl, 2,3-pentanedione, 2,3-hexanedione, and acetoin using silica gel tubes. We also collected 296 instantaneous activity and 312 instantaneous source air measurements for 18 VOCs using evacuated canisters. The highest personal full-shift exposure in part per billion (ppb) to diacetyl [geometric mean (GM) 21 ppb; 95th percentile (P95) 79 ppb] and 2,3-pentanedione (GM 15 ppb; P95 52 ppb) were measured for production workers in flavored coffee production areas. These workers also had the highest percentage of measurements above the NIOSH Recommended Exposure Limit (REL) for diacetyl (95%) and 2,3-pentanedione (77%). Personal exposures to diacetyl (GM 0.9 ppb; P95 6.0 ppb) and 2,3-pentanedione (GM 0.7 ppb; P95 4.4 ppb) were the lowest for non-production workers of facilities that did not flavor coffee. Job groups with the highest personal full-shift exposures to diacetyl and 2,3-pentanedione were flavoring workers (GM 34 and 38 ppb), packaging workers (GM 27 and 19 ppb) and grinder operator (GM 26 and 22 ppb), respectively, in flavored coffee facilities, and packaging workers (GM 8.0 and 4.4 ppb) and production workers (GM 6.3 and 4.6 ppb) in non-flavored coffee facilities. Baristas in cafés had mean full-shift exposures below the RELs (GM 4.1 ppb diacetyl; GM 4.6 ppb 2,3-pentanedione). The tasks, activities, and sources associated with flavoring in flavored coffee facilities and grinding in non-flavored coffee facilities, had some of the highest GM and P95 estimates for both diacetyl and 2,3-pentanedione. Controlling emissions at grinding machines and flavoring areas and isolating higher exposure areas (e.g., flavoring, grinding, and packaging areas) from the main production space and from administrative or non-production spaces is essential for maintaining exposure control. |
CDC Deployments to State, Tribal, Local, and Territorial Health Departments for COVID-19 Emergency Public Health Response - United States, January 21-July 25, 2020.
Dirlikov E , Fechter-Leggett E , Thorne SL , Worrell CM , Smith-Grant JC , Chang J , Oster AM , Bjork A , Young S , Perez AU , Aden T , Anderson M , Farrall S , Jones-Wormley J , Walters KH , LeBlanc TT , Kone RG , Hunter D , Cooley LA , Krishnasamy V , Fuld J , Luna-Pinto C , Williams T , O'Connor A , Nett RJ , Villanueva J , Oussayef NL , Walke HT , Shugart JM , Honein MA , Rose DA . MMWR Morb Mortal Wkly Rep 2020 69 (39) 1398-1403 Coronavirus disease 2019 (COVID-19) is a viral respiratory illness caused by SARS-CoV-2. During January 21-July 25, 2020, in response to official requests for assistance with COVID-19 emergency public health response activities, CDC deployed 208 teams to assist 55 state, tribal, local, and territorial health departments. CDC deployment data were analyzed to summarize activities by deployed CDC teams in assisting state, tribal, local, and territorial health departments to identify and implement measures to contain SARS-CoV-2 transmission (1). Deployed teams assisted with the investigation of transmission in high-risk congregate settings, such as long-term care facilities (53 deployments; 26% of total), food processing facilities (24; 12%), correctional facilities (12; 6%), and settings that provide services to persons experiencing homelessness (10; 5%). Among the 208 deployed teams, 178 (85%) provided assistance to state health departments, 12 (6%) to tribal health departments, 10 (5%) to local health departments, and eight (4%) to territorial health departments. CDC collaborations with health departments have strengthened local capacity and provided outbreak response support. Collaborations focused attention on health equity issues among disproportionately affected populations (e.g., racial and ethnic minority populations, essential frontline workers, and persons experiencing homelessness) and through a place-based focus (e.g., persons living in rural or frontier areas). These collaborations also facilitated enhanced characterization of COVID-19 epidemiology, directly contributing to CDC data-informed guidance, including guidance for serial testing as a containment strategy in high-risk congregate settings, targeted interventions and prevention efforts among workers at food processing facilities, and social distancing. |
Evidence for environmental-human microbiota transfer at a manufacturing facility with novel work-related respiratory disease
Wu BG , Kapoor B , Cummings KJ , Stanton ML , Nett RJ , Kreiss K , Abraham JL , Colby TV , Franko AD , Green FHY , Sanyal S , Clemente JC , Gao Z , Coffre M , Meyn P , Heguy A , Li Y , Sulaiman I , Borbet TC , Koralov SB , Tallaksen RJ , Wendland D , Bachelder VD , Boylstein RJ , Park JH , Cox-Ganser JM , Virji MA , Crawford JA , Edwards NT , Veillette M , Duchaine C , Warren K , Lundeen S , Blaser MJ , Segal LN . Am J Respir Crit Care Med 2020 202 (12) 1678-1688 INTRODUCTION: Workers' exposure to metalworking fluid (MWF) has been associated with respiratory disease. As part of a public health investigation of a manufacturing facility, we performed paired environmental and human sampling to evaluate cross-pollination of microbes between environment and host and possible effects on lung pathology present among workers. METHODS: Workplace environmental microbiota was evaluated in air and MWF samples. Human microbiota was evaluated in lung tissue samples from workers with respiratory symptoms found to have lymphocytic bronchiolitis and alveolar ductitis with B-cell follicles and emphysema, lung tissue controls, and in skin, nasal and oral samples from 302 workers from different areas of the facility. In vitro effects of MWF exposure on murine B-cells were assessed. RESULTS: Increased similarity of microbial composition was found between MWF samples and lung tissue samples of case workers compared to controls. Among workers in different locations within the facility, those that worked in machine shop area had skin, nasal and oral microbiota more closely related to the microbiota present in MWF samples. Lung samples from four index cases, and skin and nasal samples from workers in machine shop area were enriched with Pseudomonas, the dominant taxa in MWF. Exposure to used MWF stimulated murine B-cell proliferation in vitro, a hallmark cell subtype found in pathology of index cases. CONCLUSIONS: Evaluation of a manufacturing facility with a cluster of workers with respiratory disease supports cross-pollination of microbes from MWF to humans and suggests the potential for exposure to these microbes to be a health hazard. |
Work-related adverse respiratory health outcomes at a machine manufacturing facility with a cluster of bronchiolitis, alveolar ductitis and emphysema (BADE)
Cummings KJ , Stanton ML , Kreiss K , Boylstein RJ , Park JH , Cox-Ganser JM , Virji MA , Edwards NT , Segal LN , Blaser MJ , Weissman DN , Nett RJ . Occup Environ Med 2020 77 (6) 386-392 OBJECTIVES: Four machine manufacturing facility workers had a novel occupational lung disease of uncertain aetiology characterised by lymphocytic bronchiolitis, alveolar ductitis and emphysema (BADE). We aimed to evaluate current workers' respiratory health in relation to job category and relative exposure to endotoxin, which is aerosolised from in-use metalworking fluid. METHODS: We offered a questionnaire and spirometry at baseline and 3.5 year follow-up. Endotoxin exposures were quantified for 16 production and non-production job groups. Forced expiratory volume in one second (FEV1) decline >/=10% was considered excessive. We examined SMRs compared with US adults, adjusted prevalence ratios (aPRs) for health outcomes by endotoxin exposure tertiles and predictors of excessive FEV1 decline. RESULTS: Among 388 (89%) baseline participants, SMRs were elevated for wheeze (2.5 (95% CI 2.1 to 3.0)), but not obstruction (0.5 (95% CI 0.3 to 1.1)). Mean endotoxin exposures (range: 0.09-28.4 EU/m(3)) were highest for machine shop jobs. Higher exposure was associated with exertional dyspnea (aPR=2.8 (95% CI 1.4 to 5.7)), but not lung function. Of 250 (64%) follow-up participants, 11 (4%) had excessive FEV1 decline (range: 403-2074 mL); 10 worked in production. Wheeze (aPR=3.6 (95% CI 1.1 to 12.1)) and medium (1.3-7.5 EU/m(3)) endotoxin exposure (aPR=10.5 (95% CI 1.3 to 83.1)) at baseline were associated with excessive decline. One production worker with excessive decline had BADE on subsequent lung biopsy. CONCLUSIONS: Lung function loss and BADE were associated with production work. Relationships with relative endotoxin exposure indicate work-related adverse respiratory health outcomes beyond the sentinel disease cluster, including an incident BADE case. Until causative factors and effective preventive strategies for BADE are determined, exposure minimisation and medical surveillance of affected workforces are recommended. |
The burden of respiratory abnormalities among workers at coffee roasting and packaging facilities
Harvey RR , Fechter-Leggett ED , Bailey RL , Edwards NT , Fedan KB , Virji MA , Nett RJ , Cox-Ganser JM , Cummings KJ . Front Public Health 2020 8 5 Introduction: Respiratory hazards in the coffee roasting and packaging industry can include asthmagens such as green coffee bean and other dust and alpha-diketones such as diacetyl and 2,3-pentanedione that can occur naturally from roasting coffee or artificially from addition of flavoring to coffee. We sought to describe the burden of respiratory abnormalities among workers at 17 coffee roasting and packaging facilities. Methods: We completed medical surveys at 17 coffee roasting and packaging facilities that included interviewer-administered questionnaires and pulmonary function testing. We summarized work-related symptoms, diagnoses, and spirometry testing results among all participants. We compared health outcomes between participants who worked near flavoring and who did not. Results: Participants most commonly reported nose and eye symptoms, and wheeze, with a work-related pattern for some. Symptoms and pulmonary function tests were consistent with work-related asthma in some participants. About 5% of workers had abnormal spirometry and most improved after bronchodilator. Health outcomes were similar between employees who worked near flavoring and who did not, except employees who worked near flavoring reported more chronic bronchitis and ever receiving a diagnosis of asthma than those who did not work near flavoring. Conclusion: The symptoms and patterns likely represent overlapping health effects of different respiratory hazards, including green coffee bean and other dust that can contribute to work-related asthma, and diacetyl and 2,3-pentanedione that can contribute to obliterative bronchiolitis. Healthcare providers and occupational health and safety practitioners should be aware that workers at coffee roasting and packaging facilities are potentially at risk for occupational lung diseases. |
Collecting occupational exposure data would strengthen idiopathic pulmonary fibrosis registries
Nett RJ , Wood JM , Blackley DJ . Am J Respir Crit Care Med 2019 201 (4) 495-496 We read with interest the article by Culver and colleagues (1), who describe the use of idiopathic pulmonary fibrosis (IPF) patient registries to capture clinically relevant data on the clinical course and impact of IPF. The authors summarize the attributes of IPF registries, including descriptions of current diagnostic and management practices and collection of biological specimens (1), but they do not discuss the role patient registries can play in the collection of occupational and environmental exposure data. |
Severe lung disease characterized by lymphocytic bronchiolitis, alveolar ductitis, and emphysema (BADE) in industrial machine-manufacturing workers
Cummings KJ , Stanton ML , Nett RJ , Segal LN , Kreiss K , Abraham JL , Colby TV , Franko AD , Green FHY , Sanyal S , Tallaksen RJ , Wendland D , Bachelder VD , Boylstein RJ , Park JH , Cox-Ganser JM , Virji MA , Crawford JA , Green BJ , LeBouf RF , Blaser MJ , Weissman DN . Am J Ind Med 2019 62 (11) 927-937 BACKGROUND: A cluster of severe lung disease occurred at a manufacturing facility making industrial machines. We aimed to describe disease features and workplace exposures. METHODS: Clinical, functional, radiologic, and histopathologic features were characterized. Airborne concentrations of thoracic aerosol, metalworking fluid, endotoxin, metals, and volatile organic compounds were measured. Facility airflow was assessed using tracer gas. Process fluids were examined using culture, polymerase chain reaction, and 16S ribosomal RNA sequencing. RESULTS: Five previously healthy male never-smokers, ages 27 to 50, developed chest symptoms from 1995 to 2012 while working in the facility's production areas. Patients had an insidious onset of cough, wheeze, and exertional dyspnea; airflow obstruction (mean FEV1 = 44% predicted) and reduced diffusing capacity (mean = 53% predicted); and radiologic centrilobular emphysema. Lung tissue demonstrated a unique pattern of bronchiolitis and alveolar ductitis with B-cell follicles lacking germinal centers, and significant emphysema for never-smokers. All had chronic dyspnea, three had a progressive functional decline, and one underwent lung transplantation. Patients reported no unusual nonoccupational exposures. No cases were identified among nonproduction workers or in the community. Endotoxin concentrations were elevated in two air samples; otherwise, exposures were below occupational limits. Air flowed from areas where machining occurred to other production areas. Metalworking fluid primarily grew Pseudomonas pseudoalcaligenes and lacked mycobacterial DNA, but 16S analysis revealed more complex bacterial communities. CONCLUSION: This cluster indicates a previously unrecognized occupational lung disease of yet uncertain etiology that should be considered in manufacturing workers (particularly never-smokers) with airflow obstruction and centrilobular emphysema. Investigation of additional cases in other settings could clarify the cause and guide prevention. |
Suicides and deaths of undetermined intent among veterinary professionals from 2003 through 2014
Witte TK , Spitzer EG , Edwards N , Fowler KA , Nett RJ . J Am Vet Med Assoc 2019 255 (5) 595-608 OBJECTIVE: To analyze data for death of veterinary professionals and veterinary students, with manner of death characterized as suicide or undetermined intent from 2003 through 2014. SAMPLE: Death records for 202 veterinary professionals and veterinary students. PROCEDURES: Decedents employed as veterinarians, veterinary technicians or technologists, or veterinary assistants or laboratory animal caretakers and veterinary students who died by suicide or of undetermined intent were identified through retrospective review of National Violent Death Reporting System records. Standardized mortality ratios (SMRs) and 95% confidence intervals were calculated, and mechanisms and circumstances of death were compared among veterinary occupational groups. RESULTS: 197 veterinary professionals and 5 veterinary students had deaths by suicide or of undetermined intent. Among decedents employed at the time of death, SMRs for suicide of male and female veterinarians (1.6 and 2.4, respectively) and male and female veterinary technicians or technologists (5.0 and 2.3, respectively) were significantly greater than those for the general US population, whereas SMRs for suicide of male and female veterinary assistants or laboratory animal caretakers were not. Poisoning was the most common mechanism of death among veterinarians; the drug most commonly used was pentobarbital. For most (13/18) veterinarians who died of pentobarbital poisoning, the death-related injury occurred at home. When decedents with pentobarbital poisoning were excluded from analyses, SMRs for suicide of male and female veterinarians, but not veterinary technicians or technologists, did not differ significantly from results for the general population. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested higher SMRs for suicide among veterinarians might be attributable to pentobarbital access. Improving administrative controls for pentobarbital might be a promising suicide prevention strategy among veterinarians; however, different strategies are likely needed for veterinary technicians or technologists. |
Characteristics associated with negative attitudes toward mental illness among US veterinarians
Kassem AM , Witte TK , Nett RJ , Carter KK . J Am Vet Med Assoc 2019 254 (8) 979-985 OBJECTIVE: To explore associations between demographic, occupational, and mental health characteristics and negative attitudes toward mental illness among veterinarians. DESIGN: Cross-sectional survey. SAMPLE: 9,522 veterinarians employed in the United States. PROCEDURES: Data from a previously conducted voluntary, anonymous, web-based survey were used. Negative attitude was defined as slight or strong disagreement with 2 statements: "Treatment can help people with mental illness lead normal lives" (treatment effectiveness) and "People are generally caring and sympathetic to people with mental illness" (social support). Multivariable logistic regression was used to identify variables associated with negative attitudes. RESULTS: Of the 9,522 respondents, 6,585 (69.2%) were female, 4,523 (47.5%) were 40 to 59 years old, 291 (3.1%) had a negative attitude toward treatment effectiveness, and 4,504 (47.3%) had a negative attitude toward social support. After adjusting for other variables, negative attitude toward treatment effectiveness was significantly more likely in males, those with 10 to 19 (vs 1 to 9) years of practice experience, solo practitioners, those in government (vs "other") practice, those with evidence of serious psychological distress, and those reporting suicidal ideation after veterinary school and significantly less likely in those receiving mental health treatment. A negative attitude toward social support was significantly less likely in males and significantly more likely in 40 to 59 (vs 20 to 39) year olds, childless respondents, solo practitioners, those without membership in a veterinary association, those with evidence of serious psychological distress, those reporting depression during or after veterinary school, and those reporting suicidal ideation after veterinary school. CONCLUSIONS AND CLINICAL RELEVANCE: Characteristics such as age, sex, practice setting, and mental illness history might be useful to consider when targeting interventions to support and educate veterinarians about mental illness. |
Non-malignant respiratory disease among workers in the rubber manufacturing industry: A systematic review and meta-analysis
Thapa N , Tomasi SE , Cox-Ganser JM , Nett RJ . Am J Ind Med 2019 62 (5) 367-384 BACKGROUND: Non-malignant respiratory disease (NMRD) cases have occurred among rubber manufacturing workers. We examined exposure to rubber manufacturing emissions as a risk factor for NMRD. METHODS: From a systematic literature review, we identified case reports and assessed cross-sectional and mortality studies for strength of evidence of positive association (strong, intermediate, non-significant positive association, none) between exposure to rubber manufacturing emissions and NMRD-related morbidity and mortality, and conducted two meta-analyses. RESULTS: We analyzed 62 articles. We identified 11 cases of NMRD. Nine (30%) of 30 cross-sectional studies and one (4%) of 26 mortality studies had strong evidence. The summary odds ratio and SMR for the cross-sectional and mortality meta-analyses were 3.83 (95% confidence interval [CI], 2.28-6.51) and 0.90 (95%CI, 0.82-0.99), respectively. CONCLUSION: Available evidence supports rubber manufacturing emissions as a potential risk factor for NMRD-related morbidity. Further investigations with longer follow-up periods and inclusion of short-tenured workers could further define risks for NMRD and identify prevention strategies. |
Suicide among veterinarians in the United States from 1979 through 2015
Tomasi SE , Fechter-Leggett ED , Edwards NT , Reddish AD , Crosby AE , Nett RJ . J Am Vet Med Assoc 2019 254 (1) 104-112 OBJECTIVE To assess proportionate mortality ratios (PMRs) for suicide among male and female US veterinarians from 1979 through 2015. DESIGN PMR study. SAMPLE Death records for 11,620 veterinarians. PROCEDURES Information for veterinarians who died during 1979 through 2015 was obtained from AVMA obituary and life insurance databases and submitted to a centralized database of US death records to obtain underlying causes of death. Decedent data that met records-matching criteria were imported into a software program for calculation of PMRs for suicide stratified by sex and indirectly standardized for age, race, and 5-year calendar period with 95% confidence intervals. RESULTS 398 deaths resulted from suicide; 326 (82%) decedents were male, 72 (18%) were female, and most (298 [75%]) were ≤ 65 years of age. The PMRs for suicide for all veterinarian decedents (2.1 and 3.5 for males and females, respectively), those in clinical positions (2.2 and 3.4 for males and females, respectively), and those in nonclinical positions (1.8 and 5.0 for males and females, respectively) were significantly higher than for the general US population. Among female veterinarians, the percentage of deaths by suicide was stable from 2000 until the end of the study, but the number of such deaths subjectively increased with each 5-year period. CONCLUSIONS AND CLINICAL RELEVANCE Results of the study indicated that PMRs for suicide of female as well as male veterinarians were higher than for the general population. These data may help to inform stakeholders in the creation and implementation of suicide prevention strategies designed for veterinarians. |
Tobacco and other occupational exposures among hookah bar workers
Al-Faham Z , LeBouf RF , Nett RJ . Am J Ind Med 2018 61 (6) 543-544 Hookah bar workers are exposed to hookah smoke during work. Few studies have been published regarding the health of hookah bar workers.1,2 Hookah, also known as argileh, goza, hubble-bubble, narghile, shisha, and waterpipe, consists of a small bowl where tobacco is burned, and then the tobacco smoke travels through a water chamber and along a rubber hose (pipe) to a mouthpiece where it is inhaled by the smoker.3 Hookah bars are social gathering sites where customers often share the same hookah. Both the release of smoke from the hookah and exhalation of smoke by the smoker contribute to contaminated air in the hookah bar. Hookah use is common with an estimated 22–40% of U.S. college students having reported using hookah in the past year.3 At present, more than 40 U.S. states are known to have hookah bars.4 |
Dental personnel treated for idiopathic pulmonary fibrosis at a tertiary care center - Virginia, 2000-2015
Nett RJ , Cummings KJ , Cannon B , Cox-Ganser J , Nathan SD . MMWR Morb Mortal Wkly Rep 2018 67 (9) 270-273 In April 2016, a Virginia dentist who had recently received a diagnosis of idiopathic pulmonary fibrosis (IPF) and was undergoing treatment at a specialty clinic at a Virginia tertiary care center contacted CDC to report concerns that IPF had been diagnosed in multiple Virginia dentists who had sought treatment at the same specialty clinic. IPF is a chronic, progressive lung disease of unknown cause and associated with a poor prognosis (1). Although IPF has been associated with certain occupations (2), no published data exist regarding IPF in dentists. The medical records for all 894 patients treated for IPF at the Virginia tertiary care center during September 1996-June 2017 were reviewed for evidence that the patient had worked as a dentist, dental hygienist, or dental technician; among these patients, eight (0.9%) were identified as dentists and one (0.1%) as a dental technician, and each had sought treatment during 2000-2015. Seven of these nine patients had died. A questionnaire was administered to one of the living patients, who reported polishing dental appliances and preparing amalgams and impressions without respiratory protection. Substances used during these tasks contained silica, polyvinyl siloxane, alginate, and other compounds with known or potential respiratory toxicity. Although no clear etiologies for this cluster exist, occupational exposures possibly contributed. This cluster of IPF cases reinforces the need to understand further the unique occupational exposures of dental personnel and the association between these exposures and the risk for developing IPF so that appropriate strategies can be developed for the prevention of potentially harmful exposures. |
Development of a taxonomy of practice-related stressors experienced by veterinarians in the United States
Vande Griek OH , Clark MA , Witte TK , Nett RJ , Moeller AN , Stabler ME . J Am Vet Med Assoc 2018 252 (2) 227-233 OBJECTIVE To develop a comprehensive taxonomy of practice-related stressors experienced by US veterinarians. DESIGN Cross-sectional survey. SAMPLE A subset of 1,422 US veterinarians who provided written (vs selected) responses to a question in a previous survey regarding practice-related stressors. PROCEDURES Using grounded theory analysis, 3 researchers inductively analyzed written survey responses concerning respondents' main practice-related stressors. In 5 iterations, responses were individually coded and categorized, and a final list of practice-related stressor categories and subcategories was iteratively and collaboratively developed until theoretical and analytic saturation of the data was achieved. RESULTS A taxonomy of 15 categories of broad practice-related stressors and 40 subcategories of more specific practice-related stressors was developed. The most common practice-related stressor categories included financial insecurity (n = 289 [20.3%]), client issues (254 [17.9%]), coworker or interpersonal issues (181 [12.7%]), and work-life balance (166 [11.7%]). The most common subcategories were clients unwilling to pay (118 [8.3%]), low income (98 [6.9%]), cost of maintaining practice (56 [3.9%]), and government or state board policies (48 [3.4%]). CONCLUSIONS AND CLINICAL RELEVANCE This study provided a comprehensive list of the types of practice-related stressors experienced by US veterinarians, building a foundation for future research into relationships between job stress and mental health in this population. Frequency data on the various stressors provided an initial understanding of factors that might be contributing to high stress rates among US veterinarians. |
Deaths from non-malignant respiratory disease in styrene-exposed workers: Does obliterative bronchiolitis contribute to mortality?
Nett RJ , Edwards NT , Ruder AM , Bertke SJ , Keumala I , Cox-Ganser J , Cummings KJ . Ann Am Thorac Soc 2017 14 (5) 810-811 Since the 1970s, the U.S. National Institute for Occupational Safety and Health has monitored a cohort of 5,204 workers from two reinforced plastic boat–building facilities where exposures to styrene were characterized (1–3). Styrene is a volatile organic compound used during fiberglass production (4). An analysis of this cohort demonstrated that short-tenured workers with high styrene exposures had elevated standardized mortality ratios for nonmalignant respiratory disease (1.99; 95% confidence interval [CI], 1.38–2.79) and chronic obstructive pulmonary disease (COPD) (2.60; 95% CI, 1.70–3.81) (2). | These findings are noteworthy considering that nine cases of obliterative bronchiolitis have been reported after employment in similar industries that use styrene to make reinforced plastics (5). Nontransplantation-associated obliterative bronchiolitis occurs rarely after occupational exposure to inhalational toxins (6). In addition, rodent models have demonstrated damage to the respiratory epithelium after inhalational exposure to high concentrations of styrene (7–10). We hypothesized that styrene-related obliterative bronchiolitis contributed to the excess burden of nonmalignant respiratory disease mortality in this cohort but went unrecognized and was incorrectly categorized on death certificates as COPD (11). We therefore aimed to describe any decedents from this cohort who died of nonmalignant respiratory disease and who had possible underlying obliterative bronchiolitis. |
- Page last reviewed:Feb 1, 2024
- Page last updated:Nov 11, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure